Gestational diabetes more likely with antipsychotics

Women who take antipsychotic medicines during pregnancy are more likely to suffer from gestational diabetes, research has shown. Authors of the study, published today in Archives of General Psychiatry, warn that women who need to take the drugs while pregnant should be monitored closely for diabetes as well as for deviating fetal growth.

Researchers from the Karolinska Institutet and Uppsala University in Sweden used data from national health registers to look for associations between women’s use of antipsychotics during pregnancy and their risk of gestational diabetes, as well as changes in fetal growth. They looked at prescriptions filled by women who had given birth between July 2005 and December 2009, for olanzapine and/or clozapine (169 women), other antipsychotics (338 women), and no antipsychotics (357,696 women).

They said: “Gestational diabetes was more than twice as common in mothers who used antipsychotics (seven mothers [4.1%] for group 1 and 15 [4.4%] for group 2) than in the total population of pregnant women (5970 [1.7%]).”

In addition, women who took antipsychotics during pregnancy were more likely to have had babies who were small for gestational age (SGA) than those who took none, but after adjustment for maternal factors – including smoking – the increase in risk was no longer significant.

There was no association between women’s use of olanzapine and/or clozapine during pregnancy and their babies being born large for gestational age, except regarding head circumference.

The researchers commented: “In conclusion, maternal use of antipsychotics during pregnancy, regardless of the drug group, is associated with an increased risk of gestational diabetes.

“The increased risk of giving birth to an SGA infant observed among women treated with antipsychotics during pregnancy is probably an effect of confounding factors, such as smoking.”

They concluded: “Pregnant women treated with antipsychotics should be closely monitored for gestational diabetes and deviating fetal growth.”