Artefactual increasing frequency of omphaloceles in the Northern Netherlands: lessons for systematic analysis of apparent epidemics.

BACKGROUND: While monitoring birth defects in a registry, statistically significant increases in prevalence occasionally occur. In the European Registration Of Congenital Anomalies (EUROCAT) in the Northern Netherlands 20000 births are monitored every year. For omphaloceles, a steady increase in the prevalence from 0.86 per 10000 live- and stillbirths in 1981-1983 to 3.11 per 10000 live- and stillbirths in 1994 was seen in the three northern provinces of The Netherlands. METHODS: A stepwise enquiry into this increase, which included checking for misclassification and change in coding and ascertainment when necessary, was done. All cases of omphalocele and associated or similar birth defects registered at the EUROCAT registry were retrieved and if necessary recoded. RESULTS: This study showed that the increase reported previously was not a true time trend. A few cases of e.g. diastasis recti and trisomy 18 were misclassified. The prevalence in more recent years is comparable with that in the rest of Europe, whereas it used to be lower. There was an increase in isolated omphalocele, but the numbers are small. CONCLUSIONS: The stepwise enquiry described should be a standard procedure after noticing an increasing prevalence in a registry. A better subdivision, e.g. in isolated cases versus children with multiple congenital anomalies, before monitoring can contribute to a lower number of false positive signals.     

Maternal injuries during the periconceptional period and the risk of birth defects, National Birth Defects Prevention Study, 1997-2005

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.     

Reproductive health characteristics of marijuana and cocaine users: results from the 2002 National Survey of Family Growth

CONTEXT: Illicit drug use is associated with risky sexual behaviors in adolescents and young adults. However, few studies have examined these associations among drug users of all reproductive ages, using a control group of nonusers. METHODS: Associations between marijuana and cocaine use, and outcomes related to sexual behaviors and reproductive health, were assessed using data from the 2002 National Survey of Family Growth. Overall, 4,928 men and 7,643 women aged 15–44 were interviewed. Chi‐square tests, t tests and multivariable logistic regression analyses were used; in supplementary analyses, men and women were stratified by age‐group (25 or younger, and older than 25), to capture the understudied older adults who use drugs. RESULTS: Twenty‐seven percent of men and 16% of women reported use of marijuana or cocaine in the last year. Drug users were younger than nonusers at first vaginal sex (mean, 15.2–16.1 vs. 17.3–17.5 years) and were more likely to have engaged in risky sexual behaviors in the last year, including having had sex with a nonmonogamous partner (odds ratios, 3.3–5.2 for men and 2.9–6.5 for women), while high on alcohol or drugs (10.1–18.0 and 8.1–24.2), or in exchange for money or drugs (2.7–2.8 and 2.3–9.2). They also were more likely to have undergone STD testing or treatment. Drug use was associated with risky sexual behaviors in both age‐groups. CONCLUSION: Programs aimed at reducing sexual risks among drug users should address the behaviors of men and women of all reproductive ages.     

Maternal periconceptional alcohol consumption and risk of orofacial clefts

Using data from the National Birth Defects Prevention Study, the authors investigated the association between maternal reports of periconceptional alcohol consumption and clefting. Cases with a cleft lip, cleft palate, or both and unaffected controls delivered from 1997 through 2002 were ascertained. Interview reports of alcohol consumption were obtained from 1,749 (75.1%) case and 4,094 (68.2%) control mothers. Adjusted odds ratios and 95% confidence intervals were calculated to assess associations. Compared with odds ratios for mothers with no reported consumption, those for mothers who consumed alcohol tended to be near to (cleft lip, cleft lip with cleft palate) or to exceed (cleft palate) unity. The odds ratios associated with binge drinking were elevated but did not demonstrate significantly increased risk for any phenotype; however, the odds ratios differed by the type of alcohol consumed, particularly for cleft palate (distilled spirits > wine > beer). These odds ratios were further increased among mothers with no reported folic acid intake. Although these findings suggest that the association between alcohol consumption and clefting might be most influenced by the type of beverage consumed and folic acid intake, they are preliminary and might reflect chance associations. Such findings need exploration in additional, large studies.     

Maternal smoking and environmental tobacco smoke exposure and the risk of orofacial clefts

BACKGROUND: Smoking during pregnancy has been associated with orofacial clefts in numerous studies. However, most previous studies have not been able to assess the relation between maternal smoking and specific phenotypes (eg, bilateral clefts). METHODS: We examined the association between periconceptional maternal smoking, environmental tobacco smoke (ETS) exposure, and cleft lip with or without cleft palate (CLP) (n = 933) and cleft palate only (CPO) (n = 528) compared with infants with no major birth defects (n = 3390). Infants were born between 1 October 1997 and 31 December 2001, and exposures were ascertained from maternal telephone interviews for the National Birth Defects Prevention Study. We excluded infants who had a first-degree relative with an orofacial cleft. Effect estimates were adjusted for folic acid use, study site, prepregnancy obesity, alcohol use, gravidity, and maternal age, education, and race/ethnicity. RESULTS: Periconceptional smoking was associated with CLP (odds ratio = 1.3; 95% confidence interval = 1.0-1.6), and more strongly associated with bilateral CLP (1.7; 1.2-2.6), with a weaker association observed for CPO. Heavy maternal smoking (25+ cigarettes/day) was associated with CLP (1.8; 1.0-3.2), bilateral CLP (4.2; 1.7-10.3), and CPO with Pierre Robin sequence (2.5; 0.9-7.0). ETS exposure was not associated with CLP or CPO. CONCLUSIONS: This study confirmed the modest association between smoking and orofacial clefts that has been consistently reported, and identified specific phenotypes most strongly affected.