Drug misuse during pregnancy and fetal toxicity

The typical age at which women in North America and Europe misuse drugs encompasses their childbearing years. In the USA, according to the 2005 National Survey on Drug Use and Health, 3.9% of pregnant women admitted using illicit drugs in the previous month.1 However, maternal self-report probably underestimates the problem to a marked extent. In a sample of over 3000 babies born to an obstetric population considered high risk for drug misuse, 44% tested positive for morphine, cocaine or cannabinoid by meconium immunoassay. In contrast, only 11% of the mothers admitted illicit drug use.2 Methamphetamine is the most widely misused amphetamine with a rapid global increase in use throughout the 1990s. This now appears to be stabilising although use in the UK has remained notably lower than in other countries.3 In contrast, in a recent study of 1632 mothers across the USA, 5.2% were found to have used methamphetamine at some point during their pregnancy.4

The potential for adverse fetal effects as a result of maternal exposure to drugs and toxins is well recognised. The earliest systematic studies investigated the effects of excess maternal alcohol consumption, with its wide spectrum of sequelae including dysmorphic features, …