Antidepressants During Pregnancy Doubles the Risk of Birth Defects

Women taking antidepressants during the first trimester have up to a 10% chance of having a child with birth defects.

Taking antidepressants during pregnancy may significantly increase the risk of birth defects, a new study published by BMJ Open suggests.

Birth defects are a risk with every pregnancy, and 3% to 5% of pregnancies experience a type of defect. However, when antidepressants are taken during pregnancy, that risk doubles to between 6% and 10%. Due to these new findings, the study authors caution the use of these drugs during pregnancy.

"In pregnancy, you're treating the mother but you're worried about the unborn child, and the benefit needs to outweigh the risk," said study senior author Anick Bérard, PhD.

The authors previously found links between antidepressants and low birth weight, gestational hypertension, miscarriage, and autism. Their most recent study is the first to determine the link between birth defects and antidepressant use.

In Quebec, approximately 135,000 women become pregnant, and 7% show symptoms of mild-to-moderate depression. Less than 1% of these women show signs of severe depression, according to the study.

The investigators looked at records for 18,487 pregnant women who had depression between 1998 and 2009. Of these patients, approximately 20% were taking antidepressants during the first trimester of pregnancy.

"We only looked at the first trimester, because this is where all the organ systems are developing," Dr Bérard said. "At 12 weeks of gestation, the baby is formed."

During this time period, antidepressants may interfere with serotonin intake by the fetus, which can lead to birth defects, according to the study.

"Serotonin during early pregnancy is essential for the development of all embryonic cells, and thus any insult that disturbs the serotonin signaling process has the potential to result in a wide variety of malformations," the study authors wrote.

The investigators found that when women were taking citalopram (Celexa) during the first trimester, the risk for birth defects was 5% to 8%. There were 88 children born with birth defects that were attributed to the use of this drug.

Taking paroxetine (Paxil) was linked to heart defects, venlafaxine (Effexor) was associated with lung defects, and tricyclic antidepressants were linked to eye, ear, face, and neck defects, according to the study.

Depression during pregnancy is becoming more common, and is considered to be especially serious. Healthcare providers are prescribing antidepressants at a higher rate than ever before, and these findings suggest that it might result in serious fetal harm.

In the study, the researchers found that antidepressants were being taken in only 21 per 1000 pregnancies in 1998, which skyrocketed to 42 per 1000 in 2009.

Patients taking antidepressants during pregnancy were more likely to be older, live alone or be on welfare. They were also more likely to have comorbidities, such as diabetes, hypertension, and asthma, according to the study. These women were also not likely to have the means or support to seek treatments other than drug therapy, which include exercising or starting psychotherapy.

"There are a multitude of ways to get mild to moderate depression treated, but you need to have the time and money and also the encouragement to take advantage of them," Dr Bérard said.

The investigators caution that women and their physicians should seek alternative treatment options before resorting to antidepressants use during pregnancy.

"Given that an increasing number of women are diagnosed with depression during pregnancy, (the new) results have direct implications on their clinical management," the study concluded. "This is even more important given that the effectiveness of antidepressants during pregnancy for the treatment of the majority of cases of depression (mild to moderate depression) have been shown to be marginal. Hence, the need for caution with antidepressant use during pregnancy is warranted and alternative non-drug options should be considered."