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Objective: To examine rates and risk factors for spontaneous abortion among pregnancies conceived using assisted reproductive technology (ART).Methods: Subjects were 62,228 clinical pregnancies resulting from ART procedures initiated in 1996-1998 in US clinics. Spontaneous abortion was based on ART clinic report and was defined as loss of the entire pregnancy. Spontaneous abortion rates for ART pregnancies were compared with spontaneous abortion rates from the National Survey of Family Growth, a population-based survey of US women 15-44 years.Results: The spontaneous abortion rate among ART pregnancies was 14.7%. This was similar to rates among pregnancies reported in the National Survey of Family Growth. Among pregnancies conceived with the patient's oocytes and freshly fertilized embryos, the spontaneous abortion risk ranged from 10.1% among women 20-29 years to 39.3% among women older than 43. Spontaneous abortion risk among pregnancies conceived with donor eggs was 13.1% with little variation by patient age. Spontaneous abortion risk was increased for pregnancies conceived with frozen and thawed embryos and decreased among multiple-gestation pregnancies. Spontaneous abortion risk was increased among women reporting previous spontaneous abortions and ART attempts, and among women who used clomiphene or zygote intrafallopian transfer. Pregnancies conceived by young women, but gestated by a surrogate, were at increased risk for spontaneous abortion in comparison with young women who gestated their own pregnancies.Conclusion: These findings suggest that ART does not pose a risk for spontaneous abortion. Factors related to oocyte or embryo quality are of primary importance in assessing spontaneous abortion risk. [ABSTRACT FROM AUTHOR]

Since 1988 there has been u call for enhanced linkages between schools of public health and public health agencies that has prompted schools of public health to develop public health practice initiatives. The University of Illinois at Chicago School of Public Health conducted sundays of schools of public health and of state public health agencies in 1992 to collect baseline data on practice initiatives undertaken by academe and governmental public health agencies to enhance collaboration; follow-up surveys were undertaken in 1993, 1994 and 1996. This article describes the trends and implications of this survey of practice linkages involving schools of public health and state health agencies. [ABSTRACT FROM AUTHOR]

Background: Epidemiologic studies have reported associations between prenatal and early postnatal air pollution exposure and autism spectrum disorder (ASD); however, findings differ by pollutant and developmental window., Objectives: We examined associations between early life exposure to particulate matter ≤2.5 µm in diameter (PM2.5) and ozone in association with ASD across multiple US regions., Methods: Our study participants included 674 children with confirmed ASD and 855 population controls from the Study to Explore Early Development, a multi-site case-control study of children born from 2003 to 2006 in the United States. We used a satellite-based model to assign air pollutant exposure averages during several critical periods of neurodevelopment: 3 months before pregnancy; each trimester of pregnancy; the entire pregnancy; and the first year of life. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for study site, maternal age, maternal education, maternal race/ethnicity, maternal smoking, and month and year of birth., Results: The air pollution-ASD associations appeared to vary by exposure time period. Ozone exposure during the third trimester was associated with ASD, with an OR of 1.2 (95% CI: 1.1, 1.4) per 6.6 ppb increase in ozone. We additionally observed a positive association with PM2.5 exposure during the first year of life (OR = 1.3 [95% CI: 1.0, 1.6] per 1.6 µg/m increase in PM2.5)., Conclusions: Our study corroborates previous findings of a positive association between early life air pollution exposure and ASD, and identifies a potential critical window of exposure during the late prenatal and early postnatal periods.

Background: The 2003 revision of the US Standard Certificate of Live Birth (birth certificate) and Pregnancy Risk Assessment Monitoring System (PRAMS) are important for maternal weight research and surveillance. We examined quality of prepregnancy body mass index (BMI), gestational weight gain, and component variables from these sources., Methods: Data are from a PRAMS data quality improvement study among a subset of New York City and Vermont respondents in 2009. We calculated mean differences comparing prepregnancy BMI data from the birth certificate and PRAMS (n = 734), and gestational weight gain data from the birth certificate (n = 678) to the medical record, considered the gold standard. We compared BMI categories (underweight, normal weight, overweight, obese) and gestational weight gain categories (below, within, above recommendations), classified by different sources, using percent agreement and the simple κ statistic., Results: For most maternal weight variables, mean differences between the birth certificate and PRAMS compared with the medical record were less than 1 kg. Compared with the medical record, the birth certificate classified similar proportions into prepregnancy BMI categories (agreement = 89%, κ = 0.83); PRAMS slightly underestimated overweight and obesity (agreement = 84%, κ = 0.73). Compared with the medical record, the birth certificate overestimated gestational weight gain below recommendations and underestimated weight gain within recommendations (agreement = 81%, κ = 0.69). Agreement varied by maternal and pregnancy-related characteristics., Conclusions: Classification of prepregnancy BMI and gestational weight gain from the birth certificate or PRAMS was mostly similar to the medical record but varied by maternal and pregnancy-related characteristics. Efforts to understand how misclassification influences epidemiologic associations are needed.

Objective: Mothers of advanced maternal age (AMA) at childbirth (age ≥35 years) may have different perceptions of autism spectrum disorder (ASD) risk, independent of sociodemographic factors, that may affect ASD identification. We aimed to estimate associations between AMA and both age of a child's first evaluation noting developmental concerns and time from first evaluation to first ASD diagnosis., Methods: We used data for 8-year-olds identified with ASD in the 2008 to 2012 Autism and Developmental Disabilities Monitoring Network. We estimated differences in age at first evaluation noting developmental concerns and time to first ASD diagnosis by AMA using quantile and Cox regression., Results: Of 10,358 children with ASD, 19.7% had mothers of AMA. AMA was associated with higher educational attainment and previous live births compared with younger mothers. In unadjusted analyses, AMA was associated with earlier first evaluation noting developmental concerns (median 37 vs 40 mo) and patterns in time to first evaluation (hazard ratio: 1.12, 95% confidence interval: 1.06-1.18). Associations between AMA and evaluation timing diminished and were no longer significant after adjustment for socioeconomic and demographic characteristics. Children's intellectual disability did not modify associations between AMA and timing of evaluations., Conclusion: Advanced maternal age is a sociodemographic factor associated with younger age of first evaluation noting developmental concerns in children with ASD, but AMA was not independently associated likely, because it is a consequence or cofactor of maternal education and other sociodemographic characteristics. AMA may be a demographic factor to consider when aiming to screen and evaluate children at risk for ASD.

Background: The association between excessive gestational weight gain and preterm delivery is unclear, as is the association between low gestational weight gain and preterm delivery among overweight and obese women., Methods: Using data from the Pregnancy Risk Assessment Monitoring System in 21 states, we estimated the risk of very (20-31 weeks) and moderately (32-36 weeks) preterm delivery associated with a combination of prepregnancy body mass index (BMI) and gestational weight gain among 113,019 women who delivered a singleton infant during 1996-2001. We categorized average weight gain (kilograms per week) as very low (<0.12), low (0.12-0.22), moderate (0.23-0.68), high (0.69-0.79), or very high (>0.79). We categorized prepregnancy BMI (kg/m) as underweight (<19.8), normal (19.8-26.0), overweight (26.1-28.9), obese (29.0-34.9), or very obese (>or=35.0). We examined associations for all women and for all women with no complications adjusting for covariates., Results: There was a strong association between very low weight gain and very preterm delivery that varied by prepregnancy BMI, with the strongest association among underweight women (adjusted odds ratio = 9.8; 95% confidence interval = 7.0-13.8) and the weakest among very obese women (2.3; 1.8-3.1). Very low weight gain was not associated with moderately preterm delivery for overweight or obese women. Women with very high weight gain had approximately twice the odds of very preterm delivery, regardless of prepregnancy BMI., Conclusions: This study supports concerns about very low weight gain during pregnancy, even among overweight and obese women, and also suggests that high weight gain, regardless of prepregnancy BMI, deserves further investigation.

Objective: To examine the association of maternal hemoglobin during pregnancy with preterm birth and small for gestational age (SGA)., Methods: We performed a retrospective cohort analysis of hemoglobin and birth outcome among 173,031 pregnant women who attended publicly funded health programs in ten states and delivered a liveborn infant at 26-42 weeks' gestation. We defined preterm as less than 37 weeks' gestation and SGA as less than the tenth percentile of a US fetal growth reference., Results: Risk of preterm birth was increased in women with low hemoglobin level in the first and second trimester. The odds ratio (OR) for preterm birth with moderate-to-severe anemia during the first trimester (more than three standard deviations [SD] below reference median hemoglobin, equivalent to less than 95 g/L at 12 weeks' gestation) was 1.68 (95% confidence interval [CI] 1.29, 2. 21). Anemia was not associated with SGA. High hemoglobin level during the first and second trimester was associated with SGA but not preterm birth. The ORs for SGA in women with very high hemoglobin level during the first and second trimester (more than three SDs above reference median hemoglobin, equivalent to greater than 149 g/L at 12 weeks' gestation and greater than 144 g/L at 18 weeks') were 1.27 (95% CI 1.02, 1.58) and 1.79 (95% CI 1.49, 2.15), respectively., Conclusion: These data highlight the importance of considering anemia and high hemoglobin level as indicators for adverse pregnancy outcome. An elevated hemoglobin level (greater than 144 g/L) is an indicator for possible pregnancy complications associated with poor plasma volume expansion, and should not be mistaken for good iron status.

Objective: To evaluate whether advice on pregnancy weight gain from health care professionals, women's target weight gain (how much weight women thought they should gain), and actual weight gain corresponded with the 1990 Institute of Medicine recommendations., Methods: Predominantly white, middle-class women participating in a mail panel reported their prepregnancy weights, heights, and advised and target weight gains on a prenatal questionnaire (n = 2237), and their actual weight gains on a neonatal questionnaire (n = 1661). Recommended weight gains were categorized for women with low body mass index (BMI) (less than 19.8 kg/m2) as 25-39 lb; for women with average BMI (19.8-26.0 kg/m2) as 25-34 lb; and for women with high BMI (more than 26.0-29.0 kg/m2) and very high BMI (more than 29.0 kg/m2) as 15-24 lb., Results: Twenty-seven percent of the women reported that they had received no medical advice about pregnancy weight gain. Among those who received advice, 14% (95% confidence interval [CI] 12%, 16%) had been advised to gain less than the recommended range and 22% (95% CI 20%, 24%) had been advised to gain more than recommended. The odds of being advised to gain more than recommended were higher among women with high BMIs and with very high BMIs compared with women with average BMIs. Black women were more likely than white women to report advice to gain less than recommended. Advised and target weight gains were associated strongly with actual weight gain. Receiving no advice was associated with weight gain outside the recommendations., Conclusion: Greater efforts are required to improve medical advice about weight gain during pregnancy.

We examined associations between weight gain (kg) per week of pregnancy and net weight gain per week of pregnancy (weight gain - birth weight/weeks of gestation at delivery) and preterm delivery in a population of 266,172 low-income women. Risk of preterm delivery was lowest among women with intermediate weight gain (0.35 to <0.46 kg/week) and net weight gain (0.27 to <0.37 kg/week). Both lower and higher weight gains and net weight gains per week were associated with an increased risk for preterm delivery. Associations, however, were not uniform across body mass index categories. Compared with women gaining 0.35 to <0.46 kg/week, preterm risk differences (95% confidence limits) for women gaining <0.10 kg/week were +9.5% (+6.5, +12.4) for underweight women, +6.7% (+5.6, +7.9) for average-weight women, +3.5% (+2.0, +4.9) for overweight women, and +0.4% (-0.4, +1.2) for obese women. The opposite pattern was observed with high weight gain. Preterm risk differences for weight gains >0.65 kg/week ranged from +0.8% (-0.7, +2.1) for underweight women, to +2.5% (+1.3, +3.9) for obese women. We also evaluated weight gain per week in the latter part of pregnancy (from week 14 to delivery). The same basic patterns were observed; however, variation in the associations across body mass index groups was not as marked.

Objective: To examine associations between pregnancy weight gain outside and within ranges recommended by the Institute of Medicine and birth weight by both prepregnant body mass index (BMI) and race-ethnicity., Methods: Mean birth weight and incidence of term low birth weight (LBW, less than 2500 g) and high birth weight (more than 4500 g) were compared across BMI-pregnancy weight gain-race-ethnicity strata. Subjects were 173,066 white, black, and Hispanic low-income pregnant women attending prenatal nutrition programs between 1990 and 1993., Results: Among low and average BMI women (all race-ethnicity groups), weight gain within Institute of Medicine ranges resulted in significant LBW reductions; further LBW reductions at gains beyond Institute of Medicine ranges were offset by increasing high birth weight risk. Among women of high and obese BMI, LBW trends were less pronounced; thus, the benefit of gaining within the Institute of Medicine range was less apparent. Although blacks in every BMI-weight gain category had lower mean birth weights than white women, gaining in the upper end of the Institute of Medicine ranges did not provide a consistent LBW reduction for black women; adjusted LBW odds ratios and 95% confidence intervals for gains in the upper relative to the lower half of the Institute of Medicine range were 1.3 (0.8, 2.1), 0.7 (0.5, 1.03), 0.3 (0.2, 0.8), and 1.3 (0.7, 2.5) for black women of low, average, high, and obese BMI, respectively., Conclusion: Institute of Medicine pregnancy weight gain ranges recommended for low and average BMI women appear reasonable, but recommendations for high and obese BMI women require further evaluation. The recommendation that black women in all BMI groups strive for gains toward the upper ends of the ranges is not supported clearly by these data.

Several recent examinations of the state of public health have called for enhanced linkages between schools of public health and public health agencies, prompting federal health agencies and schools of public health to develop practice initiatives. Surveys of schools of public health and of state public health agencies were conducted in 1992 to collect baseline data on practice links between the two agencies; follow-up surveys were undertaken in 1993 and 1994. Responses reveal that a substantial amount of interaction between schools and agencies has been occurring for some time, but that until recently much of the interaction has been informal and between individuals or departments rather than institution-wide. Both frequency and formalization of such collaborations have increased, reflecting a growing emphasis on public health practice activities at schools of public health together with public health agencies.

Objective: To explore associations between race, preterm delivery, etiologic classification of preterm delivery, and perinatal mortality., Methods: The study population consisted of 13,010 black and 19,007 white mother-infant pairs delivered at Chicago-area hospitals in 1988-1989 categorized as term or preterm births. Preterm births were further divided by severity and etiology. Black-white differences in perinatal mortality within groups were calculated and adjusted for birth weight and other potential confounding variables., Results: Black women were nearly twice as likely as whites to experience preterm (before 37 weeks' gestation) and very preterm (before 32 weeks' gestation) delivery associated with premature rupture of membranes (PROM) or classified as idiopathic. Although black infants were also found to have twice the perinatal mortality risk of white infants (relative risk [RR] 2.1, 95% confidence interval [CI] 1.7-2.5), the overall preterm perinatal mortality rates did not differ between black and white women (RR 1.0, 95% CI 0.8-1.2). However, among preterm births, perinatal mortality was not uniform within categories of medical etiology. The mortality risk was the same for black and white infants born preterm following polyhydramnios or placental complications (RR 1.1, 95% CI 0.6-1.9), the same for black and white infants born preterm after labor induction (RR 1.1, 95% CI 0.6-1.9), and higher for black infants classified as idiopathic preterm deliveries (RR 1.6, 95% CI 1.1-2.3). In contrast, mortality rates tended to be lower for black infants born preterm following PROM-amnionitis (RR 0.8, 95% CI 0.5-1.2). The idiopathic disparity was explained by a differential birth weight distribution (adjusted RR 1.1, 95% CI 0.7-1.9); however, the apparent survival benefit among black infants born preterm following PROM increased even further after adjustment for birth weight (adjusted RR 0.4, 95% CI 0.2-0.7)., Conclusion: Black infants born preterm after PROM appear to have a survival advantage compared with their white counterparts, an effect not observed within other etiologic categories of preterm delivery.