Atypical antipsychotic use during pregnancy and birth defect risk: National Birth Defects Prevention Study, 1997-2011

Abstract

Purpose: To examine the prevalence of, and factors associated with, atypical antipsychotic use among U.S. pregnant women, and potential associations between early pregnancy atypical antipsychotic use and risk for 14 birth defects.

Methods: We analyzed data from the National Birth Defects Prevention Study (1997-2011), a U.S. population-based case-control study examining risk factors for major structural birth defects.

Results: Atypical antipsychotic use during pregnancy was more common among women with pre-pregnancy obesity, and women who reported illicit drug use before and during pregnancy, smoking during pregnancy, alcohol use during pregnancy, or use of other psychiatric medications during pregnancy. We observed elevated associations (defined as a crude odds ratio [cOR] ≥2.0) between early pregnancy atypical antipsychotic use and conotruncal heart defects (6 exposed cases; cOR: 2.3, 95% confidence interval [CI]: 0.9-6.1), and more specifically Tetralogy of Fallot (3 exposed cases; cOR: 2.5, 95% CI: 0.7-8.8), cleft palate (4 exposed cases, cOR: 2.5, 95% CI: 0.8-7.6), anorectal atresia/stenosis (3 exposed cases, cOR: 2.8, 95% CI: 0.8-9.9), and gastroschisis (3 exposed cases, cOR: 2.1, 95% CI: 0.6-7.3).

Conclusions: Our findings support the close clinical monitoring of pregnant women using atypical antipsychotics. Women treated with atypical antipsychotics generally access healthcare services before pregnancy; efforts to reduce correlates of atypical antipsychotic use might improve maternal and infant health in this population.

Keywords: Antipsychotics; Birth defects; Mental health; Pharmacoepidemiology.

Figure 1.

Participant selection for the estimation of prevalence and maternal factors associated with atypical antipsychotic use during pregnancy, and associations between early pregnancy atypical antipsychotic use and specific birth defects, National Birth Defects Prevention Study, 1997–2011 ^aSample used in the calculation of prevalence estimates for atypical antipsychotic medication use during pregnancy and maternal factors associated with use. Pregnancy was defined as the month prior to conception through the end of pregnancy. ^bAnticonvulsant medications included in this exclusion can be found in the National Institute of Mental Health anticonvulsant medication list (NIMH, 2010). ^cEarly pregnancy was defined as the month prior to conception through the third month of pregnancy. ^dTotal sample of case and control mothers included in the analysis of early pregnancy atypical antipsychotic use and its association with birth defects; includes cases and controls exposed and unexposed to atypical antipsychotic medications.

Figure 2.

Distribution of any atypical antipsychotic medication use across pregnancy months,^a National Birth Defects Prevention Study, 1997–2011 ^aB1 corresponds to the month before conception, P1–P9 correspond to the 1st–9th month of pregnancy.