Association of vasoconstrictive exposures with risks of gastroschisis and small intestinal atresia.

Background: Gastroschisis and small intestinal atresia are congenital anomalies that may arise from vascular disruption. It is hypothesized that maternal exposure to cocaine, amphetamines, decongestants and nicotine, all of which have vasoconstrictive actions, can contribute to these defects. The present study examined risks of gastroschisis and small intestinal atresia associated with combined exposure to vasoconstrictive drugs and cigarette smoking.

Methods: This was a retrospective study conducted from 1995 to 1999 in 15 cities across the United States and Canada. Mothers of 205 gastroschisis cases, 127 small intestinal atresia cases, 381 malformed controls and 416 nonmalformed controls were interviewed within 6 months of delivery.

Results: Reported vasoconstrictive drugs included pseudoephedrine, phenylpropanolamine, ephedrine and methylenedioxymethamphetamine. Combined exposure to vasoconstrictive drugs and cigarette smoking in the first 2.5 months of pregnancy was reported by 9% of gastroschisis cases, 9% of small intestinal atresia cases and 4% of controls. Multivariate-adjusted odds ratios, controlling for the effects of age, education, income, other drug use and alcohol intake, were 2.1 (95% confidence interval = 1.0-4.4) for gastroschisis and 2.8 (1.1-6.9) for small intestinal atresia. Risks of each defect increased with increasing level of cigarettes (P for trend = 0.019 and 0.012, respectively). Vasoconstrictive drug use among smokers of 20 or more cigarettes a day increased gastroschisis risk 3.6-fold (1.3-10.3) and small intestinal atresia risk 4.2-fold (1.1-16.2).

Conclusions: These findings provide further evidence of vascular disruption as an etiology for gastroschisis and small intestinal atresia.