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BACKGROUND Clomiphene citrate (CC) is the first line drug for subfertility treatment. Studies assessing the association between CC and birth defects have been inconclusive. METHODS We used data from the National Birth Defects Prevention Study, a population-based, multi-site case–control study of major birth defects. Women from 10 US regions with deliveries affected by at least one of >30 birth defects (cases) and mothers of live born infants without a major birth defect (controls) who delivered October 1997–December 2005 were interviewed. The exposure of interest was reported CC use in the period from 2 months before conception through the first month of pregnancy. Women who conceived using assisted reproductive technology were excluded. Thirty-six birth defect categories with at least three exposed cases were studied. Multiple logistic regression was used to control for potential confounders. RESULTS CC use was reported by 1.4% of control mothers (94/6500). Among 36 case-groups assessed, increased adjusted odds ratios (aOR) were found [all: aOR, 95% confidence interval (CI)] for anencephaly (2.3, 1.1–4.7), Dandy–Walker malformation (4.4, 1.7–11.6), septal heart defects (1.6, 1.1–2.2), muscular ventricular septal defect (4.9, 1.4–16.8), coarctation of aorta (1.8, 1.1–3.0), esophageal atresia (2.3, 1.3–4.0), cloacal exstrophy (5.4, 1.6–19.3), craniosynostosis (1.9, 1.2–3.0) and omphalocele (2.2, 1.1–4.5). CONCLUSIONS Several associations between CC use and birth defects were observed. However, because of the small number of cases, inconsistency of some findings with previous reports, and the fact that we cannot assess the CC effect separately from that of the subfertility, these associations should be interpreted cautiously. [ABSTRACT FROM AUTHOR]

Background: Maternal injuries during pregnancy are common and can cause adverse pregnancy outcomes. We sought to describe factors related to injury during pregnancy. Methods: We analyzed data from the National Birth Defects Prevention Study (NBDPS), a population-based, case-control study of birth defects in 10 U.S. states. We estimated the proportion of control mothers, a random sample of mothers delivering infants without major birth defects in the study regions, who reported an injury during pregnancy. We assessed associations with maternal and paternal characteristics using logistic regression to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI). Results: Between October 1997 and December 2005, 490 (7.4%) of 6609 mothers reported 527 injuries during pregnancy. Falls caused over half of reported injuries during pregnancy (51.6%), and 9.5% of reported injuries were intentionally inflicted. Mothers who reported an injury during pregnancy were more likely to be aged <18 years vs. 18-29 years (aOR 2.84, 95% CI 1.54-5.23) and less likely to be aged ≥30 years (aOR 0.67, 95% CI 0.51-0.89). They were more likely to use alcohol during pregnancy (aOR for nonbinge drinking 1.38, 95% CI 1.05-1.81), to smoke during pregnancy (aOR 1.37, 95% CI 1.02-1.85), to have epilepsy (aOR 3.31, 95% CI 1.48-7.38), and to be employed (aOR 1.44, 95% CI 1.08-1.93) than mothers who did not report an injury. Conclusions: We identified several factors associated with maternal injury during pregnancy, an important step in identifying women who may be at higher risk and in designing interventions to prevent injuries during pregnancy. [ABSTRACT FROM AUTHOR]

Objective: This study assessed reported use of assisted reproductive technology (ART) and other (non-ART) fertility treatments among a population-based sample and examined factors related to use. Methods: The data for this study were collected as part of the National Birth Defects Prevention Study (NBDPS), limited to women from the control group who delivered liveborn infants with no major birth defects. We described prevalence of the use of ART and clomiphene citrate (the most commonly used non-ART treatment) by demographic and lifestyle factors and examined associations among use of fertility treatments and pregnancy outcomes, timing of prenatal care initiation, and use of prenatal testing technologies. Results: Overall, 4.2% of women reported any type of maternal fertility treatment use; 1.0% reported ART use, 1.6% reported clomiphene citrate use without ART, and 1.7% reported other fertility treatments. Women who reported any fertility treatment type were more likely than women with an unassisted conception to be non-Hispanic white, >30 years of age, and more highly educated. Overall, women who reported ART use were more likely than women who reported unassisted pregnancy to have an amniocentesis; however, this association was no longer evident after adjustment for maternal age. Conclusions: Fertility treatment use and type of treatment vary by maternal characteristics. This information may be useful to inform a broad maternal and child health audience about the growing use of fertility treatments, including who is using the treatments and the choices they are making about prenatal care. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Craniosynostosis, a malformation caused by premature closure of 1 or more cranial sutures, is a rare birth defect usually of unknown cause; however, it is often associated with advanced maternal age. Because fertility treatments are also associated with increased maternal age, this study investigated the possible association between fertility treatments and craniosynostosis. METHODS: Data from the Birth Defect Risk Factor Surveillance study were used, which included infants who were delivered from 1993 through 1997 in California, Georgia, and Iowa. Cases were defined as infants who had nonfamilial, nonsyndromic craniosynostosis and were ascertained through existing birth defect surveillance systems. Controls, infants without birth defects, were selected from the same regions and time period. RESULTS: Mothers of 99 case infants and 777 control infants from the 3 study locations participated in this study by completing a telephone interview. Unadjusted analyses showed associations with craniosynostosis for mothers who had used clomiphene citrate (odds ratio[OR]: 3.8; 95% confidence interval [CI]: 1.1-12.3), artificial insemination (OR: 4.2; 95% CI: 0.8-9.4), or assisted reproductive techniques (OR: 4.2; 95% CI: 0.5-27.3). CONCLUSIONS: This is the first study that has found associations between fertility treatments and craniosynostosis. However, the numbers are small; therefore, the results should be viewed with caution. [ABSTRACT FROM AUTHOR]

Summary Tinker SC, Reefhuis J, Dellinger AM, Jamieson DJ, the National Birth Defects Prevention Study. Maternal injuries during the periconceptional period and the risk of birth defects, National Birth Defects Prevention Study, 1997-2005. Paediatric and Perinatal Epidemiology 2011; 25: 487-496. Maternal injuries during pregnancy are common (∼7% prevalence). However, few studies have examined the association between maternal injuries and birth defects. The National Birth Defects Prevention Study is a population-based case-control study of birth defects in 10 US states. Cases were ascertained through surveillance; controls were randomly selected from infants delivered without major birth defects in the study regions. Mothers completed a telephone interview on exposures before and during pregnancy, including injuries. We assessed associations between periconceptional (month before until the end of the third month of pregnancy) maternal injuries and birth defects. We used logistic regression to estimate adjusted odds ratios (AORs) and 95% confidence intervals (CI). Periconceptional injuries were associated with interrupted aortic arch type B [AOR = 5.2, 95% CI 1.2, 23.2]; atrioventricular septal defect [AOR = 2.2, 95% CI 1.1, 4.4]; pulmonary atresia [AOR = 3.2, 95% CI 1.6, 6.4]; tricuspid atresia [AOR = 2.8, 95% CI 1.2, 6.7]; hypoplastic left heart syndrome [AOR = 2.0, 95% CI 1.1, 3.4]; anorectal atresia/stenosis [AOR = 1.7, 95% CI 1.0, 2.7]; longitudinal limb deficiency [AOR = 2.1, 95% CI 1.1, 3.9]; and gastroschisis [AOR = 1.8, 95% CI 1.2, 2.8]. Associations with longitudinal limb deficiency, gastroschisis and hypoplastic left heart syndrome were stronger for intentional injuries. Our results suggest maternal injury during the periconceptional period, particularly those inflicted intentionally, may be associated with select birth defects. This analysis was hypothesis-generating, with many associations tested. Further research is warranted. [ABSTRACT FROM AUTHOR]

Objectives: Given that approximately half of all pregnancies in the United States are unplanned, the authors sought to understand the relation between pregnancy intention and health behaviors. Methods: Mothers of live-born infants without major birth defects were interviewed as part of the National Birth Defects Prevention Study. The interview assessed pregnancy intention as well as exposures to vitamins, alcohol, tobacco, illicit drugs, occupational hazards, exogenous heat (e.g., hot tubs and saunas) and caffeine. Crude odds ratios and 95% confidence intervals were calculated and stratified analyses were performed to assess interaction. Multiple logistic regression was used to calculate adjusted odds ratios. Results: Both before and after the diagnosis of pregnancy, women with unintended pregnancies were more likely to use illicit drugs, smoke, be exposed to environmental smoke, and not take folic acid or multivitamins. The degree to which women altered behaviors after they realized they were pregnant was also associated with their pregnancy intention status. For certain behaviors, maternal age or parity altered the association between pregnancy intention and changing behaviors after awareness of pregnancy. Conclusion: Pregnancy intention status is a key determinant of pregnancy-related behavior. To improve reproductive outcomes, preconceptional and prenatal programs should consider a woman's desire for pregnancy. [ABSTRACT FROM AUTHOR]

To evaluate the representativeness of controls in an ongoing, population-based, case-control study of birth defects in 10 centers across the United States, researchers compared 1997-2003 birth certificate data linked to selected controls (n = 6,681) and control participants (n = 4,395) with those from their base populations (n = 2,468,697). Researchers analyzed differences in population characteristics (e.g., percentage of births at > or =2,500 g) for each group. Compared with their base populations, control participants did not differ in distributions of maternal or paternal age, previous livebirths, maternal smoking, or diabetes, but they did differ in other maternal (i.e., race/ethnicity, education, entry into prenatal care) and infant (i.e., birth weight, gestational age, and plurality) characteristics. Differences in distributions of maternal, but not infant, characteristics were associated with participation by selected controls. Absolute differences in infant characteristics for the base population versus control participants were < or =1.3 percentage points. Differences in infant characteristics were greater at centers that selected controls from hospitals compared with centers that selected controls from electronic birth certificates. These findings suggest that control participants in the National Birth Defects Prevention Study generally are representative of their base populations. Hospital-based control selection may slightly underascertain infants affected by certain adverse birth outcomes. [ABSTRACT FROM AUTHOR]