By Dr Ananya Mandal, MD
There has been a debate on the use of antidepressant medication in pregnant women. Depression during pregnancy is, of course, difficult for the woman. In addition, depression that continues in the postpartum period may interfere with caretaking and bonding with the newborn.
The latest on a series of studies on this issue, published Monday in the Archives of General Psychiatry, shows benefits and risks to continuing medication during pregnancy and concludes that more study is needed on the topic. As many as 6% of pregnant women take antidepressants.
To understand the issue the researchers from Netherlands studied 7,696 pregnant women, which included 570 women with depression who were not on medication and 99 women with depression who were being treated with selective serotonin reuptake inhibitors (SSRIs), a common class of antidepressants.
Most of the mothers (7,027, or 91.3%), who had few depressive symptoms and did not use SSRIs, formed the control group. Another 570 mothers (7.4%) had clinically relevant depressive symptoms but did not use SSRIs, while the remaining 99 mothers (1.3%) used SSRIs during pregnancy. Mean depression scores on the depression scale of the Brief Symptom Inventory were 0.10 in the control group, 1.45 in the women with depressive symptoms but no SSRIs, and 0.74 for the women taking SSRIs.
They found that the untreated, depressed women were more likely to have babies with reduced body growth, including reduced fetal head size, while depressed women taking SSRIs were more likely to have babies with reduced fetal head size but a normal fetal body growth. It's unclear how significant reduced fetal head growth is. It has been linked to later behavioral and psychiatric problems in other studies.
Fetal head growth is “one of the best prenatal markers of brain volume,” and reduced head growth has been linked to poor cognitive performance, behavioral problems, and psychiatric disorders later in life. “Nonetheless, we must be careful not to infer an association of SSRI use in pregnancy with future developmental problems. ... [M]ore long-term drug safety studies are needed before evidence-based recommendations can be derived,” the investigators noted.
It is possible that treated women had more severe depression than untreated women, or that they had experienced previous bouts of depression. Either scenario could affect maternal physiology, and thus fetal development, the researchers said. It also is possible that manipulating serotonin levels with SSRIs could directly affect fetal brain growth, as serotonin is known to play an important role in prenatal brain development. A third possibility is that “epiphenomena of SSRI use” such as smoking, drinking, low socioeconomic status, family stress, malnutrition, or genetic susceptibility could affect fetal head growth. However, when epiphenomena compromise fetal growth, they typically impair head growth last of all, which is known as the brain-sparing effect, authors said.
Authors note, “Trying to balance the possible negative consequences of untreated maternal depression with the unknown potential negative consequences of SSRIs remains an open debate…Prescribing antidepressant medication to pregnant women is a major controversy in current psychiatry.”
“Our results indicate a rather specific effect of SSRI use during pregnancy, which differs from [the effect of] depressive symptoms on the fetus,” said Hanan El Marroun, of the department of child and adolescent psychiatry, Sophia Children’s Hospital, Rotterdam, the Netherlands, and associates.
In addition, children born to women using SSRIs were twice as likely to be born preterm as were controls. The absolute rates of preterm birth were 5.1% in the control group, 6.3% in the mothers with depressive symptoms who weren’t taking SSRIs, and 10.1% in the mothers taking SSRIs.
This study was supported by the Sophia Children’s Hospital Foundation and the Netherlands Organization for Health Research and Development (NOHRD). The Generation R Study was supported by Erasmus Medical Centre Rotterdam, Erasmus University Rotterdam, the Netherlands Organization for Scientific Research, and NOHRD. The authors reported no relevant financial disclosures.