Antipsychotic Drugs Use During Pregnancy Do Not Increase Risk Of Birth Defects

Pregnant women were always told that taking antipsychotic medications would cause their babies to be born with defects. However, according to a new study, taking antipsychotic medications during pregnancy does not increase the risk of birth defects in newborns.

Medical News Today reported that a study of 1.3 million women in Brigham Women's Hospital in Boston, Massachusetts claimed that the use of antipsychotic drugs during pregnancy does not increase the risk of birth defects in general or any cardiac malformations.

"We did not see a meaningful increase in risk for any of the drugs with the exception of risperidone," said lead author Krista Huybrechts, of Brigham and Women's Hospital and Harvard Medical School in Boston. Researchers found that women taking risperidone had about 26 percent chance of giving birth to a child with defects.  However, there are no biological reasons why the said drug would increase the risk of birth defects while others don't.

Huybrechts and coauthors used a nationwide Medicaid database to analyze and define the exposure to antipsychotics as filling at one prescription during the first 90 days (first trimester) of pregnancy. The authors analyzed both typical (older) and atypical (newer) antipsychotics.

Findings revealed that among the 1.3 million women in the study, 9,258 women or 0.69 percent filled a prescription for an atypical antipsychotic, and 733 women or 0.05 percent filled a prescription for older antipsychotic drugs during their first trimester. It was also found that the most commonly used atypical antipsychotics (in order of frequency) were quetiapine, aripiprazole, risperidone, olanzapine, and ziprasidone, Reuters reported.

Huybrechts and her team found that 4.45 percent of births exposed to atypical antipsychotics and 3.82 percent births exposed to typical antipsychotics were linked with congenital malformations compared with 3.27 percent of births of those women who did not fill a prescription for any antipsychotics. The same findings were observed for cardiac malformations.

According to Eurekalert, although these unadjusted analyses showed an increased risk of birth defects with the use of atypical antipsychotics, the authors are convinced that they have not observed any significant increase in risk of birth defects for expecting mothers using typical or atypical antipsychotics after ruling out any coexisting mental and physical conditions, as well as related behaviors, with the exception of risperidone.

Authors also warn that the small increase in risk brought by risperidone should be interpreted with extreme caution since there are still n biological mechanism to explain the results. "This finding should therefore be interpreted as a potential safety signal that will require follow-up in other studies." Study limitations were also identified such as misclassification and selection bias, as well as the possibility that medications were not taken even though prescriptions were filled.

"Our findings suggest that use of APs [antipsychotics] early in pregnancy does not meaningfully increase the risk for congenital malformation or cardiac malformation, with the possible exception of risperidone. The findings for risperidone should be viewed as an initial safety signal that will require confirmation in other studies," the study concludes.