Antipsychotics use tied to higher risk of premature delivery, low birth weight

By Anne Harding

NEW YORK (Reuters Health) - Women who take antipsychotics during pregnancy are at increased risk of premature delivery and having a low-birth-weight infant, new research suggests.

While women on antipsychotics were also more likely to have Cesarean section delivery and adverse birth outcomes than women never prescribed the drugs, those associations were no longer significant after adjusting for other medications and health and lifestyle factors.

"Our results suggest that rather than being specific associations/effects with antipsychotics, these increased risks may be associated with other health and lifestyle factors which are more common in this group of women," Dr. Irene Petersen of University College London and her colleagues write in Schizophrenia Research, online July 30.

"These include greater levels of obesity, smoking, alcohol problems, concomitant medication and illicit drug use," they note. "It may therefore be counterproductive to discontinue antipsychotic treatment in pregnancy where such treatment is judged to carry important benefits for the mental health of the mother."

Antipsychotic medications are increasingly being used in women of childbearing age to treat bipolar disorder and severe depression, as well as schizophrenia, Dr. Petersen and her team note, and data are scarce on the safety of these medications in pregnancy.

To investigate, the researchers looked at U.K. electronic health records to compare outcomes in 416 women treated with antipsychotics during pregnancy (Cohort A), 670 who stopped using antipsychotics before becoming pregnant (Cohort B), and more than 318,000 women for whom there was no record of antipsychotic treatment before or during pregnancy (Cohort C).

Fourteen percent of Cohort A and 8% of Cohort B had records indicating illicit drug use, compared to 0.6% of Cohort C. Seventeen percent of Cohort A, 12% of Cohort B, and 6.5% of Cohort C were obese.

Among the women who continued to take antipsychotics while pregnant, 57% were also taking antidepressants and 11% were on anticonvulsants, compared to less than 2% and less than 0.5% of the women never prescribed antipsychotics, respectively.

While 25% of Cohort A and 18% of Cohort C delivered by C-section, the difference was no longer significant after adjustment for health and lifestyle factors.

Ten percent of Cohort A delivered prematurely or had low birthweight babies, versus 4.3% of Cohort B and 3.9% of Cohort C. The difference between Cohorts A and B remained significant after adjustment, while the difference between Cohorts A and C fell just short of significance.

Major congenital malformations occurred in 3.4% of Cohort A, 2.2% of Cohort B, and 2% of Cohort C, but these differences were not significant after adjustment.

The researchers found no difference in risk estimates between typical and atypical antipsychotics.

Physicians should carefully consider whether or not to recommend that women on antipsychotics go off the medication during pregnancy, Dr. Petersen told Reuters Health in a telephone interview.

"You have to weigh up the risks and benefits," she said. "For many women, they may actually benefit from continuing medication during pregnancy."

She noted that women on antipsychotics were also more likely to be obese, to use illicit drugs, and to have alcohol problems. "All these factors themselves are risk factors for adverse pregnancy outcomes," she said. "You have to be careful not just to focus on the medication."

The finding of no increased risk of birth defects is reassuring, Dr. Petersen added, especially in light of a 2008 Swedish study that also found no increased risk associated with antipsychotics after adjustment for other medications.

"For many women, the drug treatment is the least of their problems during pregnancy," she said. "Doctors should therefore help them and support them during pregnancy and be aware that they often do need treatment, because it's important for them to be in a balanced mood during pregnancy and as well after they have given birth."

SOURCE: https://bit.ly/2bMjQLH

Schizophr Res 2016.