Preemies More Likely if Mom Takes SRIs

Antidepressants during pregnancy appear to increase risk of preterm birth

(RxWiki News) Deciding whether to take certain mental health medications during pregnancy requires weighing the benefits to the mother against the risks to the baby.

A recent study has found that taking a serotonin reuptake inhibitor (SRI) while pregnant increases the risk of giving birth early, even if the mother does not experience a major episode of depression.

"Ask your OB/GYN about medication use during pregnancy."

The study, led by Kimberly Yonkers, MD, a professor of psychiatry and of obstetrics, gynecology and reproductive sciences at Yale School of Public Health, involved 2,654 pregnant women who had either had a major depressive episode while pregnant and/or had used an SRI while pregnant.

Serotonin reuptake inhibitors (SRIs) are different from selective serotonin reuptake inhibitors (SSRIs) which most people are familiar with as a class of antidepressants.

While SSRIs target the neurotransmitter of serotonin in particular, SRIs can be selective or non-selective. A non-selective inhibitor might also inhibit the reuptake of other neurotransmitters besides serotonin, such as dopamine.

In this study, a total of 320 women were taking one of the following SRIs studied: citalopram (Celexa), fluoxetine (Prozac), escitalopram (Lexapro), paroxetine (Paxil), sertraline (Zoloft), duloxetine (Cymbalta) and venlafaxine (Effexor).

Dr. Yonkers and her colleagues looked at the births of these women and tallied the number of babies who were born early (before 37 weeks), very early (before 34 weeks) or at term (after the 37th week).

Among all the women in the study, a total of 225 gave birth before the 37th week of pregnancy.

The study revealed that having a major depressive episode was not associated with preterm birth, but taking an SRI was.

Women taking one of the SRIs studied who also had a major depressive episode were about twice as likely to have a preemie than those not taking an SRI.

Those who took one but didn't have an episode of depression had a 1.6 times greater risk of having a baby between the 34th and 37th weeks.

While 16 percent of the women who took an SRI and had a depressive episode had a preemie, 10 percent of those who had a depressive episode but didn't take the SRI had preemies. Among those who took an SRI but had no episodes, 11 percent had preemies.

However, neither depression nor SRI use was linked to early preterm term (before week 34).

The study ran from 2005 to 2009 and involved women who were seeing doctors at 137 different practices or clinics in Connecticut and Massachusetts.

In a press release about the research, Dr. Yonkers said that women may be concerned that being depressed could affect their child.

“This study tells them they should not worry that they are somehow compromising their pregnancy because they are depressed," she said. "And when considering whether to take medication for depression, women should understand that the risk of preterm birth is only one of many factors they should weigh.”

The study was published May 23 in the journal Epidemiology. The research was funded by the National Institute of Child Health and Human Development at the National Institutes of Health.

Review Date: 
August 3, 2012