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Background: Carbapenems are commonly used in hospitalized infants despite a lack of complete safety data and associations with seizures in older children. We compared the incidence of adverse events in hospitalized infants receiving meropenem versus imipenem/cilastatin., Methods: We conducted a retrospective cohort study of 5566 infants treated with meropenem or imipenem/cilastatin in neonatal intensive care units managed by the Pediatrix Medical Group between 1997 and 2010. Multivariable conditional logistic regression was performed to evaluate the association between carbapenem therapy and adverse events, controlling for infant factors and severity of illness., Results: Adverse events were more common with use of meropenem compared with imipenem/cilastatin (62.8/1000 infant days versus 40.7/1000 infant days, P < 0.001). There was no difference in seizures with meropenem versus imipenem/cilastatin (adjusted odds ratio 0.96; 95% confidence interval: 0.68, 1.32). The incidence of death, as well as the combined outcome of death or seizure, was lower with meropenem use-odds ratio 0.68 (0.50, 0.88) and odds ratio 0.77 (0.62, 0.95), respectively., Conclusion: In this cohort of infants, meropenem was associated with more frequent but less severe adverse events when compared with imipenem/cilastatin.

Studying empirically derived dietary patterns is useful in understanding dietary practice. We classified women by their dietary patterns using latent class analysis of 66 foods and studied the association of these patterns with neural tube defects (NTDs) and congenital heart defects (CHDs) in the U.S. National Birth Defects Prevention Study (1997-2005). Logistic regression models used data from 1,047 with an NTD, 6,641 with a CHD, and 6,123 controls that were adjusted for maternal characteristics and tested the effect modification of multivitamin supplement use. Four latent dietary patterns were identified: prudent, Western, low-calorie Western, and Mexican. Among participants who did not use supplements, those in the Mexican, Western, and low-calorie Western classes were significantly more likely (odds ratios of 1.6, 1.5, and 1.4, respectively) to have offspring born with NTDs than were those in the prudent class after adjustment of for dietary folic acid intake. In contrast, among supplement users, there was no difference in the incidence of NTDs between classes. Associations between dietary class and CHD subgroups were not modified by supplement use except for tetralogy of Fallot; among supplement users, those in the Western class were twice as likely (95% confidence interval: 1.4, 2.8) as the prudent class to have offspring with tetralogy of Fallot. Women who adhered to a Western diet were 1.2 (95% confidence interval: 1.03, 1.35) times more likely to have an infant with septal heart defect than were women who adhered to a prudent diet. A prudent dietary pattern, even with folate fortification, may decrease the risk of NTDs and some heart defects.

High serum follicle-stimulating hormone (FSH) levels have been associated with diminished ovarian reserve; however, the association between high urinary FSH and reduced natural fertility has yet to be established. We sought to characterize the relationship between a single or multiple measurements of early follicular phase urinary FSH and fertility. Women (n = 209), 30 to 44 years old with no history of infertility, who had been trying to conceive for less than 3 months, provided early follicular phase urine. Participants subsequently kept a diary to record bleeding and intercourse and conducted standardized pregnancy testing for up to 6 months. A subset of women (N = 95) collected urine on cycle day 3 for up to 6 cycles. Urine was analyzed for FSH and creatinine (cr) corrected. Proportional hazard models were used to calculate fecundability ratios (FRs). Urinary FSH levels across cycles from the same woman were highly correlated (adjusted intraclass correlation = .77); within-woman variance was 3-fold lower than variance among women. Women with an initial urinary FSH level <7 mIU/mg cr exhibited a nonsignificant reduction in the probability of pregnancy (adjusted FR 0.71, 95% confidence interval [CI]: 0.45-1.13), as did women with elevated urinary FSH (≥12 mIU/mg cr; adjusted FR 0.78, 95% CI: 0.46-1.32). Using the most recent or maximum urinary FSH value did not strengthen the association. In the general population, urinary FSH levels appear to be nonlinearly associated with fertility; however, broad CIs indicate a lack of statistical significance. Repetitive testing appears to be of little benefit.

Background: This paper presents an application of quantitative ion character-activity relationships (QICAR) to estimate associations of human cardiovascular (CV) diseases (CVDs) with a set of metal ion properties commonly observed in ambient air pollutants. QICAR has previously been used to predict ecotoxicity of inorganic metal ions based on ion properties., Objectives: The objective of this work was to examine potential associations of biological end points with a set of physical and chemical properties describing inorganic metal ions present in exposures using QICAR., Methods: Chemical and physical properties of 17 metal ions were obtained from peer-reviewed publications. Associations of cardiac arrhythmia, myocardial ischemia, myocardial infarction, stroke, and thrombosis with exposures to metal ions (measured as inference scores) were obtained from the Comparative Toxicogenomics Database (CTD). Robust regressions were applied to estimate the associations of CVDs with ion properties., Results: CVD was statistically significantly associated (Bonferroni-adjusted significance level of 0.003) with many ion properties reflecting ion size, solubility, oxidation potential, and abilities to form covalent and ionic bonds. The properties are relevant for reactive oxygen species (ROS) generation, which has been identified as a possible mechanism leading to CVDs., Conclusion: QICAR has the potential to complement existing epidemiologic methods for estimating associations between CVDs and air pollutant exposures by providing clues about the underlying mechanisms that may explain these associations.

Latent class models are useful for classifying subjects by dietary patterns. Our goals were to use latent transition models to identify dietary patterns during pregnancy and postpartum, to estimate the prevalence of these dietary patterns, and to model transition probabilities between dietary patterns as a function of covariates. Women who were enrolled in the Pregnancy, Infection, and Nutrition Study (University of North Carolina, 2000-2005) were followed for 1 year postpartum, and their diets were assessed in the second trimester and at 3 and 12 months postpartum (n = 519, 484, and 374, respectively) by using a food frequency questionnaire. After adjusting for energy intake, parity, smoking status, race, and education, we identified 3 dietary patterns and named them "prudent," "health conscious Western," and "Western." Nulliparas were 2.9 and 2.1 times more likely to be in the "prudent" class than the "health conscious Western" or the "Western" class, respectively. The 3 dietary patterns were very stable, with the "health conscious Western" class being the least stable; the probability for staying in the same class was 0.74 and 0.87 at 3 and 12 months postpartum, respectively. Breastfeeding mothers were more likely than nonbreastfeeding mothers to switch dietary pattern class (P = 0.0286). Except for breastfeeding mothers, most women did not switch dietary patterns from pregnancy to postpartum.

Background: We describe the incidence, risk factors and outcomes of invasive candidiasis in infants >1500 g birth weight., Methods: We conducted a retrospective cohort study of infants >1500 g birth weight discharged from 305 neonatal intensive care units in the Pediatrix Medical Group from 2001 to 2010. Using multivariable logistic regression, we identified risk factors for invasive candidiasis., Results: Invasive candidiasis occurred in 330 of the 530,162 (0.06%) infants. These were documented from positive cultures from ≥1 of these sources: blood (n = 323), cerebrospinal fluid (n = 6) or urine from catheterization (n = 19). Risk factors included day of life >7 (odds ratio [OR]: 25.2; 95% confidence interval: 14.6-43.3), vaginal birth (OR: 1.6 [1.2-2.3]), exposure to broad-spectrum antibiotics (OR: 1.6 [1.1-2.4]), central venous line (OR: 1.8 [1.3-2.6]) and platelet count <50,000/mm (OR: 3.7 [2.1-6.7]). All risk factors had poor sensitivities, low positive likelihood ratios and low positive predictive values. The combination of broad-spectrum antibiotics and low platelet count had the highest positive likelihood ratio (46.2), but the sensitivity of this combination was only 4%. Infants with invasive candidiasis had increased mortality (OR: 2.2 [1.3-3.6])., Conclusions: Invasive candidiasis is uncommon in infants >1500 g birth weight. Infants at greatest risk are those exposed to broad-spectrum antibiotics and with platelet counts of <50,000/mm(3).

The dynamic aspect of early life growth is not fully captured by typical analyses, which focus on one specific time period. To better understand how infant and young child growth relate to the development of adult body composition, the authors characterized body mass index (BMI) trajectories using latent class growth analysis (LCGA) and evaluated their association with adult body composition. Data are from the Cebu Longitudinal Health and Nutrition Survey, which followed a birth cohort to age 22 years (n = 1749). In both males and females, LCGA identified seven subgroups of respondents with similar BMI trajectories from 0 to 24 months (assessed with bimonthly anthropometrics). Trajectory groups were compared with conventional approaches: (1) accelerated growth between two time points (0-4 months), (2) continuous BMI gain between two points (0-4 months and 0-24 months) and (3) BMI measured at one time point (24 months) as predictors of young adult body composition measures. The seven trajectory groups were distinguished by age-specific differences in tempo and timing of BMI gain in infancy. Infant BMI trajectories were better than accelerated BMI gain between 0 and 4 months at predicting young adult body composition. After controlling for BMI at age 2 years, infant BMI trajectories still explained variation in adult body composition. Using unique longitudinal data and methods, we find that distinct infant BMI trajectories have long-term implications for the development of body composition.

Objective: to examine the associations between total and domain-specific moderate-to-vigorous physical activity (MVPA) during pregnancy and postpartum depressive symptoms., Design: a prospective cohort study., Participants: data were obtained from 652 women recruited from prenatal clinics at University of North Carolina Hospitals during 2001-2005 for the Pregnancy, Infection, and Nutrition (PIN) Postpartum Study., Measurements: MVPA measured at 17-22 and 27-30 weeks' gestation was investigated as a predictor of depressive symptoms assessed with the Edinburgh Postnatal Depression Scale at 3 months postpartum., Findings: total MVPA was not associated with depressive symptoms when using either 17-22 weeks' gestation or 27-30 weeks' gestation MVPA measures. In general, there were minimal associations for domain-specific MVPA. The direction of associations between depressive symptoms and work, adult and child care, and outdoor household MVPAs differed by time of measurement., Key Conclusions: the association between physical activity and postpartum depressive symptoms may differ with the timing of assessment. Additional studies (i.e. with a larger sample of women or a sample of at-risk women) following women throughout pregnancy and postpartum are needed to explore differences in the influence of physical activity on depressive symptoms., Implications for Practice: assessment of potential risk factors for elevated depressive symptoms, such as participation levels in different types of physical activity, throughout pregnancy may assist in determining who may be susceptible to postpartum depression., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Purpose: Few studies have examined the health and developmental consequences, including unintended pregnancy, of different sexual behavior initiation sequences. Some work suggests that engaging in oral-genital sex first may slow the transition to coital activity and lead to more consistent contraception among adolescents., Methods: Using logistic regression analysis, we investigated the association between sequences of sexual initiation (i.e., initiating oral-genital or vaginal sex first based on reported age of first experience) and the likelihood of subsequent teenage pregnancy among 6,069 female respondents who reported vaginal sex before age 20 years and participated in waves I and IV of the National Longitudinal Study of Adolescent Health., Results: Among female respondents initiating vaginal sex first, 31.4% reported a teen pregnancy. Among female respondents initiating two behaviors at the same age, 20.5% reported a teen pregnancy. Among female respondents initiating oral-genital sex first, 7.9% reported a teen pregnancy. In multivariate models, initiating oral-genital sex first, with a delay of at least 1 year to vaginal sex, and initiating two behaviors within the same year were each associated with a lower likelihood of adolescent pregnancy relative to teens who initiated vaginal sex first (odds ratio = .23, 95% confidence interval: .15-.37; and odds ratio = .78, 95% confidence interval: .60-.92, respectively)., Conclusions: How adolescents begin their sexual lives may be differentially related to positive and negative health outcomes. To develop effective pregnancy prevention efforts for teens and ensure programs are relevant to youths' needs, it is important to consider multiple facets of sexual initiation and their implications for adolescent sexual health and fertility., (Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Multiple metrics to characterize air pollution are available for use in environmental health analyses in addition to the standard Air Quality System (AQS) pollution monitoring data. These metrics have complete spatial-temporal coverage across a domain and are therefore crucial in calculating pollution exposures in geographic areas where AQS monitors are not present. We investigate the impact that two of these metrics, output from a deterministic chemistry model (CMAQ) and from a spatial-temporal downscaler statistical model which combines information from AQS and CMAQ (DS), have on risk assessment. Using each metric, we analyze ambient ozone's effect on low birth weight utilizing a Bayesian temporal probit regression model. Weekly windows of susceptibility are identified and analyzed jointly for all births in a subdomain of Texas, 2001-2004, and results from the different pollution metrics are compared. Increased exposures during weeks 20-23 of the pregnancy are identified as being associated with low birth weight by the DS metric. Use of the CMAQ output alone results in increased variability of the final risk assessment estimates, while calibrating the CMAQ through use of the DS metric provides results more closely resembling those of the AQS. The AQS data are still preferred when available.

Context: Identifying young adult outcomes associated with adolescent sexual behavior, including patterns of first oral, vaginal and anal sex, is critical to promoting healthy sexual development., Methods: Associations between patterns of emerging sexual behavior, defined using latent class analysis, and young adult sexual and reproductive health were examined among 9,441 respondents to Waves 1 (1994-1995), 3 (2001-2002) and 4 (2008) of the National Longitudinal Study of Adolescent Health. Logistic regression analyses examined associations between class membership and young adult outcomes, and tested for interactions by race and ethnicity., Results: Compared with respondents who initiated vaginal sex first and reported other sexual behaviors within two years, those who initiated oral and vaginal sex during the same year had similar odds of having had an STD diagnosis ever or in the last year, of having had concurrent sexual partnerships in the last year and of having exchanged sex for money. However, respondents who postponed sexual activity had reduced odds of each outcome (odds ratios, 0.2-0.4); those who initiated vaginal sex and reported only one type of sexual behavior had reduced odds of reporting STD diagnoses and concurrent partnerships (0.4-0.6). Respondents who reported early initiation of sexual activity combined with anal sex experience during adolescence had elevated odds of having had concurrent partnerships (1.6). The data suggest racial and ethnic disparities even when patterns of emerging sexual behavior were the same., Conclusions: Patterns of early sexual behavior considered high-risk may not predict poor sexual and reproductive health in young adulthood., (Copyright © 2012 by the Guttmacher Institute.)

Aims/hypothesis: The purpose of this study was to examine the association between urbanisation-related factors and diabetes prevalence in China., Methods: Anthropometry, fasting blood glucose (FBG) and community-level data were collected for 7,741 adults (18-90 years) across 217 communities and nine provinces in the 2009 China Health and Nutrition Survey to examine diabetes (FBG ≥7.0 mmol/l or doctor diagnosis). Sex-stratified multilevel models, clustered at the community and province levels and controlling for individual-level age and household income were used to examine the association between diabetes and: (1) a multicomponent urbanisation measure reflecting overall modernisation and (2) 12 separate components of urbanisation (e.g., population density, employment, markets, infrastructure and social factors)., Results: Prevalent diabetes was higher in more-urbanised (men 12%; women 9%) vs less-urbanised (men 6%; women 5%) areas. In sex-stratified multilevel models adjusting for residential community and province, age and household income, there was a twofold higher diabetes prevalence in urban vs rural areas (men OR 2.02, 95% CI 1.47, 2.78; women, OR 1.94, 95% CI 1.35, 2.79). All urbanisation components were positively associated with diabetes, with variation across components (e.g. men, economic and income diversity, OR 1.42, 95% CI 1.20, 1.66; women, transportation infrastructure, OR 1.18, 95% CI 1.06, 1.32). Community-level variation in diabetes was comparatively greater for women (intraclass correlation [ICC] 0.03-0.05) vs men (ICC ≤0.01); province-level variation was greater for men (men 0.03-0.04; women 0.02)., Conclusions/interpretation: Diabetes prevention and treatment efforts are needed particularly in urbanised areas of China. Community economic factors, modern markets, communications and transportation infrastructure might present opportunities for such efforts.

Breastfeeding rates in the United States are low, and one possible reason may be the high prevalence of overweight/obesity among women of childbearing age. This analysis examined the association between pregravid body mass index and breastfeeding duration, and explored whether depressive symptoms, perceived stress and anxiety during pregnancy mediated this relationship. Participants (n = 550) in the Pregnancy, Infection and Nutrition Postpartum Study were recruited through prenatal clinics prior to 20 weeks gestation and followed to 12 months post-partum. Duration of any breastfeeding was categorized as none, less than 4 months, 4-6 months, 7-12 months and more than 12 months (referent). Exclusive breastfeeding was categorized as less than 1 month, 1 to less than 4 months and 4 months or more (referent). Being overweight/obese before pregnancy (35.7% of 550) was inversely associated with the durations of any and exclusive breastfeeding. Women who entered pregnancy overweight or obese were more likely to not initiate breastfeeding [relative risk ratio (RRR)=5.39 (95% confidence interval: 2.41, 12.04)] and to breastfeed less than 4 months [RRR=2.38 (1.33, 4.27)] compared with women of normal weight status. Among women who initiated breastfeeding, being overweight or obese vs. normal weight was related to exclusively breastfeeding less than 1 month [RRR=2.09 (1.24, 3.51)]. We did not find evidence to support mediation by depressive symptoms, perceived stress or anxiety during pregnancy. Future research needs to explore the reasons behind the association between overweight/obesity and breastfeeding duration., (© 2011 Blackwell Publishing Ltd.)

The aim of this study was to examine infant feeding and the long-chain polyunsaturated fatty acid (LCPUFA) concentration of breast milk and formulas in relation to infant development. The prospective Pregnancy, Infection and Nutrition Study (n=358) collected data on breastfeeding, breast milk samples and the formulas fed through 4months post-partum. At 12months of age, infants' development was assessed (Mullen Scales of Early Learning). Linear regression was used to examine development in relation to breastfeeding, breast milk docosahexaenoic acid (DHA) and arachidonic acid (AA) concentration, and DHA and AA concentration from the combination of breast milk and formula. The median breast milk DHA concentration was 0.20% of total fatty acids [interquartile range (IQR)=0.14, 0.34]; median AA concentration was 0.52% (IQR=0.44, 0.63). Upon adjustment for preterm birth, sex, smoking, race and ethnicity and education, breastfeeding exclusivity was unrelated to development. Among infants exclusively breastfed, breast milk LCPUFA concentration was not associated with development (Mullen composite, DHA: adjusted β=-1.3, 95% confidence interval: -10.3, 7.7). Variables combining DHA and AA concentrations from breast milk and formula, weighted by their contribution to diet, were unassociated with development. We found no evidence of enhanced infant development related to the LCPUFA content of breast milk or formula consumed during the first four post-natal months., (© 2011 Blackwell Publishing Ltd.)

Background: During early pregnancy, the placenta develops to meet the metabolic demands of the foetus. The objective of this analysis was to examine the effect of malaria parasitaemia prior to 20 weeks' gestation on subsequent changes in uterine and umbilical artery blood flow and intrauterine growth restriction., Methods: Data were analysed from 548 antenatal visits after 20 weeks' gestation of 128 women, which included foetal biometric measures and interrogation of uterine and umbilical artery blood flow. Linear mixed effect models estimated the effect of early pregnancy malaria parasitaemia on uterine and umbilical artery resistance indices. Log-binomial models with generalized estimating equations estimated the effect of early pregnancy malaria parasitaemia on the risk of intrauterine growth restriction., Results: There were differential effects of early pregnancy malaria parasitaemia on uterine artery resistance by nutritional status, with decreased uterine artery resistance among nourished women with early pregnancy malaria and increased uterine artery resistance among undernourished women with early pregnancy malaria. Among primigravidae, early pregnancy malaria parasitaemia decreased umbilical artery resistance in the late third trimester, likely reflecting adaptive villous angiogenesis. In fully adjusted models, primigravidae with early pregnancy malaria parasitaemia had 3.6 times the risk of subsequent intrauterine growth restriction (95% CI: 2.1, 6.2) compared to the referent group of multigravidae with no early pregnancy malaria parasitaemia., Conclusions: Early pregnancy malaria parasitaemia affects uterine and umbilical artery blood flow, possibly due to alterations in placentation and angiogenesis, respectively. Among primigravidae, early pregnancy malaria parasitaemia increases the risk of intrauterine growth restriction. The findings support the initiation of malaria parasitaemia prevention and control efforts earlier in pregnancy.

Objective: To determine whether women who entered pregnancy overweight or obese were less likely to follow American Academy of Pediatrics guidelines for introducing complementary foods to infants after 4 months of age. In addition, we explored whether psychological factors accounted for any of the effect of pregravid body mass index on age of complementary food introduction., Design: A prospective cohort study from 2001 to 2005 that recruited pregnant women between 15 to 20 gestational weeks with follow-up through 12 months postpartum from University of North Carolina hospitals (n=550)., Statistical Analysis: Multinomial models were used to estimate relative risk ratios. The outcome was age of complementary food introduction, categorized as younger than 4 months of age, 4 to 6 months, and 6 months or later (referent). Maternal body mass index was categorized as underweight (<18.5), normal weight (18.5 to 24.9), and overweight/obese (≥25). A series of regression analyses tested mediation by psychological factors measured during pregnancy (depressive symptoms, stress, and anxiety)., Results: More than a third of the study population (35.7% of 550) entered pregnancy overweight/obese. The majority of participants (75.3%) introduced foods to their infants between 4 and 6 months of age. Compared with normal-weight women, those who were overweight/obese before pregnancy were more likely (relative risk ratios=2.22 [95% CI 1.23 to 4.01]) to introduce complementary foods before the infant was 4 months old, adjusting for race, education, and poverty status. Depressive symptoms, stress, and anxiety did not account for any of the effect of pregravid overweight/obesity on early food introduction., Conclusions: The results suggest that overweight and obese women are more likely to introduce complementary foods early and that psychological factors during pregnancy do not influence this relationship. Future studies need to explore why overweight/obese women are less likely to meet the American Academy of Pediatrics recommendations for the introduction of complementary food., (Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)

Human phthalate exposure is ubiquitous, but little is known regarding predictors of urinary phthalate levels. To explore this, 50 pregnant women aged 18-38 years completed two questionnaires on potential phthalate exposures and provided a first morning void. Urine samples were analyzed for 12 phthalate metabolites. Associations with questionnaire items were evaluated via Wilcoxon tests and t-tests, and r-squared values were calculated in multiple linear regression models. Few measured factors were statistically significantly associated with phthalate levels. Individuals who used nail polish had higher levels of mono-butyl phthalate (P=0.048) than non-users. Mono-benzyl phthalate levels were higher among women who used eye makeup (P=0.034) or used makeup on a regular basis (P=0.004). Women who used cologne or perfume had higher levels of di-(2-ethylhexyl) phthalate metabolites. Household products, home flooring or paneling, and other personal care products were also associated with urinary phthalates. The proportion of variance in metabolite concentrations explained by questionnaire items ranged between 0.31 for mono-ethyl phthalate and 0.42 for mono-n-methyl phthalate. Although personal care product use may be an important predictor of urinary phthalate levels, most of the variability in phthalate exposure was not captured by our relatively comprehensive set of questionnaire items.

Most previous studies of preterm birth have considered risk factors in isolation rather than examining the collective impact of multiple candidate determinants. In order to examine the combined impact of a set of behavioral risk factors on the risk of preterm birth, we analyzed data collected for the Pregnancy, Infection, and Nutrition Study on a range of sociodemographic, behavioral, and related factors. Women who received prenatal care at selected clinics in central North Carolina and gave birth in the period 1995-2005 were recruited into a prospective cohort study, with 4,251 women providing the required information on risk factors and pregnancy outcome. A number of demographic and behavioral attributes were modestly associated with preterm birth, with odds ratios of 1.3-1.5, including age >35, African-American ethnicity, height of 63 inches or less, parity 2+, and delivery at the academic medical center. Despite weak associations for individual risk factors, changes in a constellation of behaviors during pregnancy predict substantial shifts in the risk of preterm birth, suggesting a reduction from 8 to 3% preterm among those with a low-risk baseline profile, and a reduction from 18 to 7% preterm among those with a high-risk baseline profile. While inferences are limited by the incomplete range of available predictors, uncertainty regarding whether observed associations are causal, and substantial challenges in changing component behaviors, the possibility of substantial reduction in risk merits more serious consideration of whether behavioral interventions could markedly reduce the risk of preterm birth.

Objectives: Several epidemiological studies have suggested that certain paternal occupations may be associated with an increased prevalence of birth defects in offspring. Using data from the National Birth Defects Prevention Study, the authors investigated the association between paternal occupation and birth defects in a case-control study of cases comprising over 60 different types of birth defects (n=9998) and non-malformed controls (n=4066) with dates of delivery between 1997 and 2004., Methods: Using paternal occupational histories reported by mothers via telephone interview, jobs were systematically classified into 63 groups based on shared exposure profiles within occupation and industry. Data were analysed using bayesian logistic regression with a hierarchical prior for dependent shrinkage to stabilise estimation with sparse data., Results: Several occupations were associated with an increased prevalence of various birth defect categories, including mathematical, physical and computer scientists; artists; photographers and photo processors; food service workers; landscapers and groundskeepers; hairdressers and cosmetologists; office and administrative support workers; sawmill workers; petroleum and gas workers; chemical workers; printers; material moving equipment operators; and motor vehicle operators., Conclusions: Findings from this study might be used to identify specific occupations worthy of further investigation and to generate hypotheses about chemical or physical exposures common to such occupations.

Objective: Over-the-counter vaginal lubricants have been shown to negatively affect in vitro sperm motility. The objective of this study was to estimate the effect of vaginal lubricant use during procreative intercourse on natural fertility., Methods: Women aged 30-44 years with no history of infertility who had been trying to conceive for less than 3 months completed a baseline questionnaire on vaginal lubricant use. Subsequently, women kept a diary to record menstrual bleeding, intercourse, and vaginal lubricant use and conducted standardized pregnancy testing for up to 6 months. Diary data were used to determine the fertile window and delineate lubricant use during the fertile window. A proportional hazards model was used to estimate fecundability ratios with any lubricant use in the fertile window considered as a time-varying exposure., Results: Of the 296 participants, 75 (25%) stated in their baseline questionnaire that they use vaginal lubricants while attempting to conceive. Based on daily diary data, 57% of women never used a lubricant, 29% occasionally used a lubricant, and 14% used a lubricant frequently. Women who used lubricants during the fertile window had similar fecundability to those women who did not use lubricants (fecundability ratio 1.05, 95% confidence interval 0.59-1.85) after adjusting for age, partner race, and intercourse frequency in the fertile window., Conclusion: Lubricants are commonly used by couples during procreative intercourse. Lubricant use during procreative intercourse does not appear to reduce the probability of conceiving.

Unlabelled: Current US pregnancy-related physical activity recommendations do not provide specific guidance for vigorous intensity activity. We examined the associations between vigorous physical activity during pregnancy and length of gestation and birthweight., Methods: Women were recruited before 10 weeks gestation. At 13-16 weeks gestation, participants reported the type, frequency, and duration of their typical weekly vigorous physical activities. Activity domains included recreational, occupational, household, and child/adult care. Infant birth date was obtained from medical or vital records; if unavailable, self-report was used. Birthweight (from vital records) was studied among term births. We analyzed gestational age among 1,647 births using discrete-time survival analysis. We used logistic and linear regression to analyze preterm birth (birth at <37 weeks) and birthweight, respectively. Vigorous recreational activity was associated with longer gestation (any vs. none, hazard ratio (HR) [95% CI]: 0.85 [0.70, 1.05]) and we did not detect any dose-response association. Higher frequency of vigorous recreational activity sessions (adjusted for total volume of activity) was associated with a decreased odds of preterm birth (≥ 4 sessions/week vs. 0 or 1, OR [95% CI]: 0.08 (0.006, 1.0). Birthweight was not associated with physical activity measures. In summary, vigorous physical activity does not appear to be detrimental to the timing of birth or birthweight. Our data support a reduced risk of preterm birth with vigorous recreational activity, particularly with increased frequency of recreational activity sessions. Future studies should investigate the components of physical activity (i.e., intensity, duration, and frequency) in relation to birth outcomes.

Purpose: Although the emergence of sexual expression during adolescence and early adulthood is nearly universal, little is known about patterns of initiation., Methods: We used latent class analysis to group 12,194 respondents from waves I and IV of the National Longitudinal Study of Adolescent Health (Add Health) into one of five classes based on variety, timing, spacing, and sequencing of oral-genital, anal, and vaginal sex. Multinomial logistic regression models, stratified by biological sex, examined associations between sociodemographic characteristics and class membership., Results: Approximately half of respondents followed a pattern characterized predominately by initiation of vaginal sex first, average age of initiation of approximately 16 years, and spacing of >1 year between initiation of the first and second behaviors; almost one-third initiated sexual activity slightly later but reported first experiences of oral-genital and vaginal sex within the same year. Classes characterized by postponement of sexual activity, initiation of only one type of behavior, or adolescent initiation of anal sex were substantially less common. Compared with white respondents, black respondents were more likely to appear in classes characterized by initiation of vaginal sex first. Respondents from lower socioeconomic backgrounds were more likely to be in classes distinguished by early/atypical patterns of initiation., Conclusions: A small number of typical and atypical patterns capture the emergence of sexual behavior during adolescence, but these patterns reveal complex associations among different elements of emerging sexuality that should be considered in future research., (Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

The aim of the present study was to examine the association between depressive symptoms in pregnancy and the concentration of long-chain polyunsaturated fatty acids (LCPUFAs) in breast milk. Women (n = 287) enrolled in the Pregnancy, Infection, and Nutrition Study completed the Center for Epidemiologic Studies Depression Scale in pregnancy (< 20 and 24-29 weeks) and had LCPUFAs measured in breast milk (4 months postpartum). Multiple linear regression was used to examine associations between depressive symptoms and breast milk LCPUFAs. Increasing depressive symptoms at < 20 weeks were associated with lower docosahexaenoic acid concentrations (adjusted β = -1.15, 95% confidence interval = -2.12, -0.19). No similar associations were observed with other fatty acids nor between symptoms at 24-29 weeks and LCPUFAs. Depressive symptoms, even in the subclinical range, early in pregnancy are inversely associated with breast milk docosahexaenoic acid. This may have implications for the timing of screening and interventions for perinatal depression and the nutritional value of breast milk.

Objective: To determine how gestational weight gain (GWG), categorized using the 2009 Institute of Medicine recommendations, relates to changes in offspring weight-for-age (WAZ), length-for-age (LAZ) and weight-for-length z-scores (WLZ) between early infancy and 3 years., Methods: Women with singleton infants were recruited from the third cohort of the Pregnancy, Infection, and Nutrition Study (2001-2005). Term infants with at least one weight or length measurement during the study period were included (n = 476). Multivariable linear mixed effects regression models estimated longitudinal changes in WAZ, LAZ and WLZ associated with GWG., Results: In early infancy, compared with infants of women with adequate weight gain, those of women with excessive weight gains had higher WAZ, LAZ and WLZ. Excessive GWG ≥ 200% of the recommended amount was associated with faster rates of change in WAZ and LAZ and noticeably higher predicted mean WAZ and WLZ that persisted across the study period., Conclusions: GWG is associated with significant differences in offspring anthropometrics in early infancy that persisted to 3 years of age. More longitudinal studies that utilize maternal and paediatric body composition measures are necessary to understand the nature of this association., (© 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.)

Background: Much of the epidemiologic research on risk factors for fibroids, the leading indication for hysterectomy, relies on self-reported outcome. Self-report is subject to misclassification because many women with fibroids are undiagnosed. The purpose of this analysis was to quantify the extent of misclassification and identify associated factors., Methods: Self-reported fibroid status was compared to ultrasound screening from 2046 women in Right From The Start (RFTS) and 869 women in the Uterine Fibroid Study (UFS). Log-binomial regression was used to estimate sensitivity (Se) and specificity (Sp) and examine differences by ethnicity, age, education, body mass index, parity, and miscarriage history., Results: Overall sensitivity was ≤0.50. Sensitivity was higher in blacks than whites (RFTS: 0.34 vs. 0.23; UFS: 0.58 vs. 0.32) and increased with age. Parous women had higher sensitivity than nulliparae, especially in RFTS whites (Se ratio=2.90; 95% confidence interval [CI]: 1.51, 5.60). Specificity was 0.98 in RFTS and 0.86 in UFS. Modest ethnic differences were seen in UFS (Sp ratio, black vs. white=0.90; 95% CI: 0.81, 0.99). Parity was inversely associated with specificity, especially among UFS black women (Sp ratio=0.84; 95% CI: 0.73, 0.97). Among women who reported a previous diagnosis, a shorter time interval between diagnosis and ultrasound was associated with increased agreement between the two measures., Conclusions: Misclassification of fibroid status can differ by factors of etiologic interest. These findings are useful for assessing (and correcting) bias in studies using self-reported clinical diagnosis as the outcome measure.

Background: Correlates of prenatal physical activity can inform interventions, but are not well-understood., Methods: Participants in the Pregnancy, Infection, and Nutrition 3 Study were recruited before 20 weeks gestation. Women self-reported frequency, duration, and mode of moderate and vigorous physical activities. We used logistic regression to identify correlates of any physical activity (≥10 minutes/week of any mode), any recreational activity (≥10 minutes/week), and high volume recreational activity (either ≥150 minutes/week of moderate or ≥75 minutes/week of vigorous). Our analysis included 1752 women at 19-weeks gestation and 1722 at 29 weeks., Results: Higher education, white race, and enjoyment of physical activity were positively correlated with all 3 outcomes. Any recreational activity was negatively associated with parity, body mass index, and history of miscarriage. The associations of history of miscarriage and body mass index differed at 19 weeks compared with 29 weeks. Single marital status, health professional physical activity advice, and time for activity were associated with high volume recreational activity only., Conclusions: Correlates of physical activity differed by mode and volume of activity and by gestational age. This suggests that researchers planning physical activity interventions should consider the mode and amount of activity and the gestational age of the participants.

Background: Few studies measure physical activity objectively or at multiple time points during postpartum. We describe physical activity at 3- and 12-months postpartum among a cohort of women using both self-reported and objective measures., Methods: In total, 181 women completed the 3-month postpartum measures, and 204 women completed the 12-month postpartum measures. Participants wore an ActiGraph accelerometer for 1 week and completed in-home interviews that included questions on physical activity. A cohort of 80 women participated at both time points. Poisson regression models were used to determine whether physical activity differed over time for the cohort., Results: For the cohort, average counts/minute were 364 at 3-months postpartum and 394 at 12-months postpartum. At both time periods for the cohort, vigorous activity averaged 1 to 3 minutes/day, and moderate activity averaged 16 minutes/day. Sedentary time averaged 9.3 hours at 3-months postpartum and 8.8 hours at 12-months postpartum, out of a 19-hour day. Average counts/minute increased and sedentary behavior declined from 3- to 12-months postpartum., Conclusion: Interventions are needed to help women integrate more moderate to vigorous physical activity and to capitalize on the improvements in sedentary behavior that occur during postpartum.

Exposure to toxic metals during the prenatal period carries the potential for adverse developmental effects to the fetus, yet such exposure remains largely unmonitored in the United States. The aim of this study was to assess maternal exposure to four toxic metals (arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb)) in a cohort of pregnant women in North Carolina. We analyzed blood samples submitted to the North Carolina Department of Health and Human Services for blood typing to assess toxic metal levels in pregnant women (n = 211) across six North Carolina counties. Whole blood metal concentrations were measured by inductively coupled plasma mass spectrometry. The association between maternal characteristics, including county of residence, age, and race, and metal exposure was analyzed using multiple linear regression analysis. A large fraction of the blood samples showed detectable levels for each of the four metals. Specifically, As (65.7%), Cd (57.3%), Hg (63.8%), and Pb (100%) were detected in blood samples. Moreover, compared with adult females participating in the Fourth National Report on Human Exposure to Environmental Chemicals and guidelines for pregnant women, some women in the sample population exceeded benchmark levels of Cd, Hg, and Pb. Evidence from this pilot study indicates that pregnant women in North Carolina are exposed to As, Cd, Hg, and Pb and suggests that factors related to maternal county of residence and race may impact maternal exposure levels. As increased levels of one or more of these metals in utero have been associated with detrimental developmental and reproductive outcomes, further study is clearly warranted to establish the impacts to newborns.

A real-time surveillance method is developed with emphasis on rapid and accurate detection of emerging outbreaks. We develop a model with relatively weak assumptions regarding the latent processes generating the observed data, ensuring a robust prediction of the spatiotemporal incidence surface. Estimation occurs via a local linear fitting combined with day-of-week effects, where spatial smoothing is handled by a novel distance metric that adjusts for population density. Detection of emerging outbreaks is carried out via residual analysis. Both daily residuals and AR model-based detrended residuals are used for detecting abnormalities in the data given that either a large daily residual or an increasing temporal trend in the residuals signals a potential outbreak, with the threshold for statistical significance determined using a resampling approach., (© 2011, The International Biometric Society.)

Background: Single-nucleotide polymorphisms (SNP) in alcohol metabolism genes are associated with squamous cell carcinoma of the head and neck (SCCHN) and may influence cancer risk in conjunction with alcohol. Genetic variation in the oxidative stress pathway may impact the carcinogenic effect of reactive oxygen species produced by ethanol metabolism. We hypothesized that alcohol interacts with these pathways to affect SCCHN incidence., Methods: Interview and genotyping data for 64 SNPs were obtained from 2,552 European- and African-American subjects (1,227 cases and 1,325 controls) from the Carolina Head and Neck Cancer Epidemiology Study, a population-based case-control study of SCCHN conducted in North Carolina from 2002 to 2006. We estimated ORs and 95% confidence intervals (CI) for SNPs and haplotypes, adjusting for age, sex, race, and duration of cigarette smoking. P values were adjusted for multiple testing using Bonferroni correction., Results: Two SNPs were associated with SCCHN risk: ADH1B rs1229984 A allele (OR = 0.7; 95% CI, 0.6-0.9) and ALDH2 rs2238151 C allele (OR = 1.2; 95% CI, 1.1-1.4). Three were associated with subsite tumors: ADH1B rs17028834 C allele (larynx, OR = 1.5; 95% CI, 1.1-2.0), SOD2 rs4342445 A allele (oral cavity, OR = 1.3; 95% CI, 1.1-1.6), and SOD2 rs5746134 T allele (hypopharynx, OR = 2.1; 95% CI, 1.2-3.7). Four SNPs in alcohol metabolism genes interacted additively with alcohol consumption: ALDH2 rs2238151, ADH1B rs1159918, ADH7 rs1154460, and CYP2E1 rs2249695. No alcohol interactions were found for oxidative stress SNPs., Conclusions and Impact: Previously unreported associations of SNPs in ALDH2, CYP2E1, GPX2, SOD1, and SOD2 with SCCHN and subsite tumors provide evidence that alterations in alcohol and oxidative stress pathways influence SCCHN carcinogenesis and warrant further investigation., (© 2011 AACR.)

Objective: To determine if exposure to disinfection by-products (DBPs) during gestation increases the risk of adverse birth outcomes, specifically term small for gestational age (SGA) birth, preterm birth (PTB), and very PTB (<32 weeks' gestation)., Methods: We used weekly measurements total trihalomethanes (TTHMs), five haloacetic acids (HAA5), and total organic halides (TOX) collected from two distribution systems to evaluate the associations between DBP concentrations and term SGA, PTB, and very PTB using logistic regression., Results: We found no associations between DBPs and term-SGA. In the site with higher concentrations of bromine-containing DBPs, we found an association between TOX and PTB; this association was larger, though less precise, for very PTB., Conclusions: Our results do not support an association between TTHMs or HAA5 and the birth outcomes investigated, but an association was found between increased TOX and PTB.

Study Objective: To evaluate the change in premenstrual syndrome (PMS) symptoms in women with heavy periods who underwent endometrial ablation., Design: The study used a prospective, single-arm cohort of adult women who were to undergo NovaSure endometrial ablation for heavy menses who also reported symptoms of PMS. A brief baseline survey was done to evaluate menstrual bleeding and baseline PMS symptoms, and two 30-day prospective validated measures of PMS were used. Follow-up surveys were sent at 4 to 6 months and included both the brief survey questions and the validated measures of PMS (Canadian Task Force classification II-3)., Measurements and Main Results: Thirty-six women with heavy periods who were to undergo endometrial ablation had PMS symptoms and completed all surveys at baseline and follow-up. The mean age was 41.4 years, with a mean body mass index of 26.7. Most (27/36, 75%) had failed hormonal management. All measures of PMS showed significant improvement after endometrial ablation. Self-rating of PMS symptoms on a scale of 0 (none) to 10 (severe) improved from a baseline of 7.4 to a follow-up rating of 3.2 (p <.05). The vast majority of women (35/36, 97%) reported improvement in PMS after undergoing endometrial ablation. Both validated measures of PMS, Daily Symptoms Report and Daily Record of Severity of Symptoms, showed statistically significant improvement in PMS symptoms., Conclusion: Women with heavy menses and associated PMS symptoms who undergo NovaSure endometrial ablation showed improvement in PMS symptoms, as well as reduced menstrual bleeding., (Copyright © 2011 AAGL. Published by Elsevier Inc. All rights reserved.)

In this article, we develop a latent class model with class probabilities that depend on subject-specific covariates. One of our major goals is to identify important predictors of latent classes. We consider methodology that allows estimation of latent classes while allowing for variable selection uncertainty. We propose a Bayesian variable selection approach and implement a stochastic search Gibbs sampler for posterior computation to obtain model-averaged estimates of quantities of interest such as marginal inclusion probabilities of predictors. Our methods are illustrated through simulation studies and application to data on weight gain during pregnancy, where it is of interest to identify important predictors of latent weight gain classes., (© 2010, The International Biometric Society.)

Background: Postpartum women are at increased risk for developing depression, which can contribute to the ill health of the mother and her family. Previous research indicates that mothers who are physically active during leisure experience lower levels of postpartum depressive symptoms than do inactive mothers. The objective of this investigation was to examine the associations between total and domain-specific moderate to vigorous physical activity (MVPA) and depressive symptoms postpartum., Methods: Data were obtained from 550 women who participated in the Pregnancy, Infection, and Nutrition (PIN) Postpartum Study, a prospective cohort of mothers who delivered liveborn infants from October 2002 to December 2005 in North Carolina. Three-month postpartum MVPA was investigated as a predictor of 12-month postpartum depressive symptoms., Results: Those who participated in MVPA had two times the odds of developing elevated depressive symptoms at 12 months postpartum than those with no MVPA (odds ratio [OR] 2.00, 95% confidence interval [CI] 0.71-6.75). Different associations were suggested when examining domain-specific MVPA. Those participating in adult and child care and indoor household MVPA at 3 months postpartum had more than double the odds of developing elevated depressive symptoms at 12 months postpartum (OR 2.66, 95% CI 1.03, 8.11 and OR 2.72, 95% CI 0.96-10.18, respectively). Work MVPA conferred a doubling of the odds (OR 1.95, 95% CI 0.46-7.13), but recreational and outdoor household MVPA showed no associations with depressive symptoms., Conclusions: Associations between MVPA and depressive symptoms differed by domain among postpartum women. Future studies of postpartum depressive symptoms should explore reasons for differences in physical activity by domain.

Racial/ethnic disparities in birthweight are a large source of differential morbidity and mortality worldwide and have remained largely unexplained in epidemiologic models. We assess the impact of maternal ancestry and census tract residence on infant birth weights in New York City and the modifying effects of race and nativity by incorporating random effects in a multilevel linear model. Evaluating the significance of these predictors involves the test of whether the variances of the random effects are equal to zero. This is problematic because the null hypothesis lies on the boundary of the parameter space. We generalize an approach for assessing random effects in the two-level linear model to a broader class of multilevel linear models by scaling the random effects to the residual variance and introducing parameters that control the relative contribution of the random effects. After integrating over the random effects and variance components, the resulting integrals needed to calculate the Bayes factor can be efficiently approximated with Laplace's method.

Aim: Our objective was to examine the associations between maternal psychological health (trait anxiety, perceived stress, and depressive symptoms) during pregnancy or postpartum and infant visual, language, motor, and overall cognitive development., Study Design and Methods: In the prospective Pregnancy, Infection, and Nutrition Study (2001-2006), central North Carolina women completed self-administered questionnaires during pregnancy to assess trait anxiety and depressive symptoms. An in-person interview assessed maternal perceived stress and depressive symptoms in the 4th postpartum month. Infant development was assessed at 12 months using the Mullen Scales of Early Learning (n=358). Multiple linear regression with restricted cubic splines was used to examine potential non-linear associations between trait anxiety, perceived stress, and depressive symptoms in relation to Mullen sub-scales and Composite scores., Results: Increasing maternal anxiety was associated with poorer overall cognition (adjusted β for Composite=-0.2, 95% CI: -0.4, 0.0). Postpartum stress was positively associated with language development and general cognition (adjusted β for Expressive Language=0.2, 95% CI: 0.0, 0.4; adjusted β for Composite=0.3, 95% CI: 0.0, 0.6). Elevated depressive symptoms throughout pregnancy and postpartum were associated with better fine motor skills (adjusted β=9.7, 95% CI: 3.9, 15.5). Anxiety, postpartum depressive symptoms and stress were associated with gross motor skills in a non-linear fashion, as were postpartum depressive symptoms and stress with expressive language., Conclusions: Maternal trait anxiety, depressive symptoms and stress had little negative influence on infant cognitive development. In fact, moderate psychosocial distress may slightly accelerate motor development in particular, and some aspects of language., (Published by Elsevier Ireland Ltd.)

Prenatal depression confers health risks for both mother and family. Physical activity may promote better mental health; however, few studies have examined the influence of physical activity on prenatal depression. Data from 1,220 women enrolled in the third Pregnancy, Infection, and Nutrition Study (2001-2005) were used to examine the associations between overall and domain-specific moderate-to-vigorous physical activity (MVPA) and depressive symptoms during pregnancy. Self-reported, past week physical activity assessed at 17-22 weeks' gestation was modeled in logistic regression with self-reported depressive symptoms assessed by the Center for Epidemiologic Studies-Depression Scale at 24-29 weeks' gestation. Active women with ≤2.67 h/week of total MVPA had almost half the odds of having high depressive symptoms as compared to women with no MVPA (odds ratio [OR] = 0.56, 95% confidence interval [CI] = 0.38, 0.83). Increased odds of elevated depressive symptoms were found for women participating in some but ≤2.25 h/week of adult and child care MVPA (OR = 1.84; 95% CI = 1.08, 3.11) and >1 h of indoor household MVPA (OR = 1.63, 95% CI = 0.99, 2.70) when compared to women with no MVPA. While overall MVPA may play a role in reducing the odds of developing elevated depressive symptoms, adult and child care and indoor household activities may increase it.

The majority of women gain more weight during pregnancy than what is recommended. Since gestational weight gain is related to short and long-term maternal health outcomes, it is important to identify women at greater risk of not adhering to guidelines. The objective of this study was to examine the relationship between body image and gestational weight gain. The Body Image Assessment for Obesity tool was used to measure ideal and current body sizes in 1,192 women participating in the Pregnancy, Infection and Nutrition Study. Descriptive and multivariable techniques were used to assess the effects of ideal body size and discrepancy score (current-ideal body sizes), which reflected the level of body dissatisfaction, on gestational weight gain. Women who preferred to be thinner had increased risk of excessive gain if they started the pregnancy at a BMI ≤26 kg/m(2) but a decreased risk if they were overweight or obese. Comparing those who preferred thin body silhouettes to those who preferred average size silhouettes, low income women had increased risk of inadequate weight gain [RR = 1.76 (1.08, 2.88)] while those with lower education were at risk of excessive gain [RR = 1.11 (1.00, 1.22)]. Our results revealed that body image was associated with gestational weight gain but the relationship is complex. Identifying factors that affect whether certain women are at greater risk of gaining outside of guidelines may improve our ability to decrease pregnancy-related health problems.

Unlabelled: Most Internet vendors offer tax-free cigarettes making them cheaper than those sold at stores. This undermines the impact that higher prices have upon reducing consumption. Most Internet tobacco sales have violated taxation and youth access laws, which led to landmark voluntary agreements in 2005 with the major credit card companies and major private shippers to ban payment transactions and shipments for all Internet cigarette sales., Objective: To assess whether these bans increased the rate of Internet Cigarette Vendors (ICVs) ceasing online sales, decreased the proportion of vendors offering banned payment and shipping options, and decreased consumer traffic to the most popular ICVs., Design: Websites in a longitudinal study of ICVs were visited in 2003 (n = 338), 2004 (n = 775), 2005 (n = 664), 2006 (n = 762), and 2007 (n = 497) to assess whether they were in business and monitor their advertised sales practices. The number of unique monthly visitors to the 50 most popular ICVs at baseline was examined for the period one year before and two years after the bans to determine whether the bans altered traffic., Results: Following the bans, the rate of ICVs ceasing online sales year to year increased, but due to an influx of new vendors, there was a net increase in ICVs. The proportion of vendors accepting banned payment options dropped from 99.2% to 37.4% after the bans, and the proportion offering banned shipping options dropped from 32.2% to 5.6%, but there was a corresponding increase in vendors offering non-banned payment options (e.g., personal checks) and shipping options (e.g., US Postal Service). Following the bans, there was a 3.5 fold decline in traffic to the most popular ICV websites., Conclusions: This promising approach to controlling the sale of restricted goods online has implications for regulating other products such as alcohol, firearms, quack cures, and medicines sold without a prescription.

Purpose: The obesity epidemic raises concerns about the impact of excessive and insufficient weight gain during pregnancy., Methods: We examined the association between gestational weight gain (GWG) and preterm birth, term small- and large-for-gestational-age (SGA and LGA), term birthweight, and term primary Cesarean delivery, considering prepregnancy body mass index (BMI) and ethnicity in a cohort of 33,872 New York City residents who gave birth between 1995 and 2003 and delivered in hospitals elsewhere in New York State., Results: Preterm birth (<37 weeks' gestation) showed a modest U-shaped relationship, with projected GWG of <10 kg and 20+ kg associated with odds ratios of 1.4 and 1.3, respectively, relative to 10 to 14 kg. The pattern was stronger for preterm birth <32 weeks' and for underweight women with low GWG and overweight/obese women with high GWG. Term SGA decreased and term LGA and birthweight increased monotonically with increasing GWG. Primary Cesarean delivery followed the same pattern as LGA, but less strongly., Conclusions: Although the study is limited by potential selection bias and measurement error, our findings support the contention that GWG may be a modifiable predictor of pregnancy outcome that warrants further investigation, particularly randomized trials, to assess whether the relation is causal., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Objective: The objective of the study was to determine the association between child BMI at age 3 years and maternal glucose concentration among women without pre-existing diabetes or a gestational diabetes mellitus (GDM) diagnosis., Research Design and Methods: Data are from the Pregnancy Infection and Nutrition and Postpartum studies and include 263 mother-child pairs. Measured weights and heights at 3 years were used to calculate age- and sex-specific BMI z scores and percentiles. Multivariable linear regression models were used to examine associations of continuous BMI z scores with maternal glucose concentration. Modified Poisson regression estimated risk ratios of child overweight/obesity (BMI ≥ 85th percentile)., Results: The mean (SD) maternal glucose concentration and prepregnancy BMI were 103.8 (23.7) mg/dL and 24.3 (5.9) kg/m(2), respectively. At 3 years, the mean (SD) child BMI z score was 0.29 (0.99), 20.9% were overweight/obese and 5.3% were obese. In the adjusted model, when compared with glucose concentration <100 mg/dL, a concentration ≥ 130 mg/dL was associated with significantly higher child BMI z score at 3 years (estimated z score difference of 0.39 [95% CI: 0.03-0.75]). With the use of the same reference category, a concentration ≥ 130 mg/dL was associated with an approximate twofold greater risk of child overweight/obesity (adjusted risk ratio 2.34 [95% CI: 1.25-4.38])., Conclusions: Fetal exposure to high maternal glucose concentration in the absence of pre-existing diabetes or GDM may contribute to the development of overweight/obesity in the offspring, independent of maternal prepregnancy BMI.

Objective: To determine whether pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) influence infant postnatal growth., Study Design: Participants were from the Pregnancy, Infection, and Nutrition study, a prospective pregnancy cohort. Term infants with weight or length measurements at approximately 6 months were included (n = 363). Multivariable regression estimated associations for weight-for-age (WAZ), length-for-age (LAZ), and weight-for-length z-scores (WLZ) and rapid infant weight gain with categorical maternal exposures defined with the 2009 Institute of Medicine recommendations., Results: Pre-pregnancy overweight and obesity were associated with higher WAZ (linear regression coefficient [β], 0.32; 95% CI, 0.04-0.61) and WLZ (β, 0.39; 95% CI, 0.02-0.76), respectively. Pre-pregnancy BMI was not associated with LAZ. Excessive GWG was associated with higher WAZ (β, 0.39; 95% CI, 0.15-0.62) and LAZ (β, 0.34; 95% CI, 0.12-0.56). Excessive GWG ≥ 200% of recommended amount was associated with higher WAZ (β, 0.68; 95% CI, 0.28-1.07), LAZ (β, 0.45; 95% CI, 0.06-0.83), and WLZ (β, 0.43; 95% CI, 0.04-0.82). Risk of rapid weight gain increased across maternal exposure categories; however, none of the estimates were significant., Conclusions: Pre-pregnancy BMI and GWG are modifiable intrauterine exposures that influence infant postnatal anthropometric outcomes. Further investigation with infant body composition measurements is warranted., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Empirical dietary patterns are derived predominantly using principal components, exploratory factor analysis (EFA), or cluster analysis. Interestingly, latent variable models are less used despite their being more flexible to accommodate important characteristics of dietary data and despite dietary patterns being recognized as latent variables. Latent class analysis (LCA) has been shown empirically to be more appropriate to derive dietary patterns than k-means clustering but has not been compared yet to confirmatory factor analysis (CFA). In this article, we derived dietary patterns using EFA, CFA, and LCA on food items, tested how well the classes from LCA were characterized by the factors from CFA, and compared participants' direct classification from LCA on food items compared with 2 a posteriori classifications from factor scores. Methods were illustrated with the Pregnancy, Infection and Nutrition Study, North Carolina, 2000-2005 (n = 1285 women). From EFA and CFA, we found that food items were grouped into 4 factors: Prudent, Prudent with coffee and alcohol, Western, and Southern. From LCA, pregnant women were classified into 3 classes: Prudent, Hard core Western, and Health-conscious Western. There was high agreement between the direct classification from LCA on food items and the classification from the 2-step LCA on factor scores [κ=0.70 (95% CI = 0.66, 0.73)] despite factors explaining only 25% of the total variance. We suggest LCA on food items to study the effect for mutually exclusive classes and CFA to understand which foods are eaten in combination. When interested in both benefits, the 2-step classification using LCA on previously derived factor scores seems promising.

Background: Earlier studies have shown an inverse association between the presence of nausea and vomiting in pregnancy (NVP) and spontaneous abortion (SAB), but no study to date has examined the effects of symptom duration on the risk of SAB., Methods: We examined NVP symptom severity and duration in relation to the occurrence of SAB. Data were collected from 2407 pregnant women in three US cities between 2000 and 2004 through interviews, ultrasound assessments and medical records abstractions. Discrete-time continuation ratio logistic survival models were used to examine the association between NVP and pregnancy loss., Results: Lack of NVP symptoms was associated with increased risk for SAB [adjusted odds ratio (OR) = 3.2, 95% confidence interval (CI): (2.4, 4.3)], compared with having any symptoms. Reduced risks for SAB were found across most maternal age groups for those with NVP for at least half of their pregnancy, but the effects were much stronger in the oldest maternal age group [OR = 0.2, 95% CI: (0.1, 0.8)]., Conclusions: The absence of NVP symptoms is associated with an increased risk of early pregnancy loss. As symptom duration decreases, the likelihood of early loss increases, especially among women in the oldest maternal age group.

We tested the hypothesis that the protective effect of parity on fibroids is due to direct pregnancy-related effects by following women from early pregnancy to postpartum period with ultrasound. Of 171 women with one initial fibroid, 36% had no identifiable fibroid at the time of postpartum ultrasound, and 79% of the remaining fibroids decreased in size., (Copyright © 2010 American Society for Reproductive Medicine. All rights reserved.)

Postpartum weight retention plays an important role in the pathway leading to obesity among women of childbearing age. The objective of this study was to examine predictors of moderate (1-10 pounds) and high (>10 pounds) postpartum weight retention using data from a prospective pregnancy cohort that followed women into the postpartum period; n = 688 and 550 women at 3 and 12 months, respectively. Analysis included descriptive statistics and predictive modeling using log-binomial techniques. The average weight retained at 3 and 12 months postpartum in this population was 9.4 lb (s.d. = 11.4) and 5.7 lb (s.d. = 13.2), respectively. At 3 months postpartum, prepregnancy weight, gestational weight gain, and hours slept during the night were associated with moderate or high weight retention, whereas having an infant hospitalized after going home and scoring in the upper 75th percentile of the Eating Attitudes Test (EAT) were associated only with high weight retention. At 12 months postpartum, prepregnancy weight, gestational weight gain, and maternal education were associated with moderate weight retention; and gestational weight gain, maternal age, race, employment status, and having an infant hospitalized at birth were associated with high weight retention. The results of this study illustrate the importance of prepregnancy weight and gestational weight gain in predicting postpartum weight retention. Furthermore, given the lack of successful intervention studies that exist to date to help women lose weight in the postpartum period, the results of this study may help to inform future interventions that focus on such aspects as hours of sleep, dealing with stress associated with a hospitalized infant, and nonclinical eating disorder symptomatology.

Objective: We sought to determine whether genetic variants associated with diabetes and obesity predict gestational weight gain., Study Design: A total of 960 participants in the Pregnancy, Infection, and Nutrition cohorts were genotyped for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity., Results: Among Caucasian and African American women (n = 960), KCNQ1 risk allele carriage was directly associated with weight gain (P < .01). In Bayesian hierarchical models among Caucasian women (n = 628), we found posterior odds ratios >3 for inclusion of TCF2 and THADA SNPs in our models. Among African American women (n = 332), we found associations between risk allele carriage and weight gain for the THADA and INSIG2 SNPs. In Bayesian variable selection models, we found an interaction between the TSPAN8 risk allele and pregravid obesity, with lower weight gain among obese risk allele carriers., Conclusion: We found evidence that diabetes and obesity risk alleles interact with maternal pregravid body mass index to predict gestational weight gain., (Copyright 2010 Mosby, Inc. All rights reserved.)

Physical activity has many well-documented health benefits for cardiovascular fitness and weight control. For pregnant women, the American College of Obstetricians and Gynecologists currently recommends 30 minutes of moderate exercise on most, if not all, days; however, very few pregnant women achieve this level of activity. Traditionally, studies have focused on examining individual or interpersonal factors to identify predictors of physical activity. There is a renewed interest in whether characteristics of the physical environment in which we live and work may also influence physical activity levels. We consider one of the first studies of pregnant women that examines the impact of characteristics of the built environment on physical activity levels. Using a socioecologic framework, we study the associations between physical activity and several factors including personal characteristics, meteorological/air quality variables, and neighborhood characteristics for pregnant women in four counties of North Carolina. We simultaneously analyze six types of physical activity and investigate cross-dependencies between these activity types. Exploratory analysis suggests that the associations are different in different regions. Therefore, we use a multivariate regression model with spatially varying regression coefficients. This model includes a regression parameter for each covariate at each spatial location. For our data with many predictors, some form of dimension reduction is clearly needed. We introduce a Bayesian variable selection procedure to identify subsets of important variables. Our stochastic search algorithm determines the probabilities that each covariate's effect is null, non-null but constant across space, and spatially varying. We found that individual-level covariates had a greater influence on women's activity levels than neighborhood environmental characteristics, and some individual-level covariates had spatially varying associations with the activity levels of pregnant women., (© 2009, The International Biometric Society.)

Purpose: Although first-trimester vaginal bleeding is an alarming symptom, few studies have investigated the prevalence and predictors of early bleeding. This study characterizes first trimester bleeding, setting aside bleeding that occurs at time of miscarriage., Methods: Participants (n = 4539) were women ages 18 to 45 enrolled in Right From the Start, a community-based pregnancy study (2000-2008). Bleeding information included timing, heaviness, duration, color, and associated pain. Life table analyses were used to describe gestational timing of bleeding. Factors associated with bleeding were investigated by the use of multiple logistic regression with multiple imputation for missing data., Results: Approximately one fourth of participants (n = 1207) reported bleeding (n = 1656 episodes), but only 8% of women with bleeding reported heavy bleeding. Of the spotting and light bleeding episodes (n = 1555), 28% were associated with pain. Among heavy episodes (n = 100), 54% were associated with pain. Most episodes lasted less than 3 days, and most occurred between gestational weeks 5 to 8. Twelve percent of women with bleeding and 13% of those without experienced miscarriage. Maternal characteristics associated with bleeding included fibroids and prior miscarriage., Conclusions: Consistent with the hypothesis that bleeding is a marker for placental dysfunction, bleeding is most likely to be observed around the time of the luteal-placental shift., (Published by Elsevier Inc.)