Comparison of trends in gastroschisis and prenatal illicit drug use rates.

Gastroschisis rates have been increasing over time, and gastroschisis risk is elevated in women of young maternal age. Similar patterns were reported for prenatal illicit drug use in Hawaii. Cases of gastroschisis and prenatal use of methamphetamine, cocaine, or marijuana among deliveries in Hawaii during 1986-2002 were identified from a common registry. The pattern of gastroschisis rates by maternal age and time period was compared to the pattern of prenatal illicit drug use rates. The prenatal marijuana use rate among gastroschisis cases was significantly greater than among the total population. Prenatal methamphetamine and cocaine rates were not significantly elevated among gastroschisis cases. The gastroschisis rate was highest among the youngest maternal age group, then declined with increasing maternal age. Only prenatal marijuana use demonstrated a similar pattern, but the ratio of the gastroschisis rate to the prenatal marijuana use rate declined with increasing maternal age. The gastroschisis rate increased during the 17-yr period. Both methamphetamine and marijuana demonstrated similar annual trends; however, the ratio of the gastroschisis rates to the illicit drug use rates varied greatly for the 2 drugs over time. The results of this investigation suggest that prenatal illicit drug use of methamphetamine, cocaine, and marijuana may not play a major role in explaining the increased risk of gastroschisis among younger mothers and the annual increases that have been reported.