A recent study observing antidepressant use and autism has found no evidence of an association between the two. Harvard T.H. Chan School of Public Health and Sweden’s Karolinska Institute researchers collaborated to study about 1.6 million babies born in Sweden from 1996 to 2012.

They concluded that there was no increased risk for autism or attention-deficit/hyperactivity disorder (ADHD) amongst babies born to women on antidepressant medication.

This study contradicts previous, longstanding evidence on the matter. In 2015, a study proved that babies exposed to selective serotonin reuptake inhibitors (SSRIs) in utero were 87% more likely to develop autism than babies who were not exposed to antidepressants antenatally. This well-publicised study roughly guided healthcare professionals in clinical decision-making until now.

Risks of in utero antidepressant exposure

A recent analysis of over 16 studies and found that babies had an 18% increased risk of developing malformations if their mothers had taken antidepressants, specifically fluoxetine, in the first trimester. The babies also had a 36% elevated risk of heart defects with this exposure.

Dr Penny Adams, an Australian expert, weighed in on this issue, “There is, statistically, significantly increased incidents of birth defects for women who have taken this drug in the first trimester of their pregnancy.”

“However, the actual numbers are so low – that even if you have an 18% increased number – it's still a low number,” she added. She also said anxiety and depression in pregnancy should still be treated and other alternatives are available.

Similar studies are such as the link between paroxetine, an SSRI, and the increased risk of developing a right ventricular outflow obstruction. Also, 10 to 30% of babies exposed to SSRIs in the third trimester showed signs of withdrawal symptoms at birth like feeding disturbances, rapid breathing and increased crying which resolved within the first two weeks.

Another study proved that babies exposed to antidepressants antenatally are more inclined to developing persistent pulmonary hypertension. However, the Center for Disease Control and Prevention in the United States relayed that the incidences and the absolute risk in these instances are low.

Effects of foregoing antidepressant intake during pregnancy

Data shows that in women with pre-existing major depressive disorder (MDD), the risk of relapse during pregnancy increases when medications are stopped. In fact, the relapse rate is 68% if drug therapy is discontinued in the first trimester.

Untreated MDD and anxiety poses serious risks to the pregnant women and their babies. The women can face suicide risks, diminished self-care and disregard breastfeeding.

The babies, on the other hand, have been proven to have an increased risk of preterm birth and low birth weight secondary to untreated maternal MDD. Not to mention, the elevated incidence of postpartum depression and its subsequent effects due to untreated antepartum depression.

Exposure to SSRI differ for each patient

To provide holistic treatment, it is imperative that clinical decisions be made with patients’ desires taken into account. Corinne Purtill, a patient with MDD, recounts during her first pregnancy, she weaned herself off antidepressants and eventually suffered a relapse. Influenced by the 2015 study, she attempted to stop the medication once again in her second pregnancy.

“I felt worse as the months wore on, but depression warps the ability to make good decisions about one’s self-care and I didn’t speak up,” she said.

“By the time I gave birth, the depression was serious enough that the hospital installed a 24-hour observer in my room to ensure I didn’t harm myself and refused to release me before an evaluation from a psychiatric consultant.”

Contrary to this case, some patients opt to continue all their medications despite being advised to stop completely as they render themselves ‘unable to function’ without it.

“It’s not one size fits all here,” remarked Katherine Economy, an obstetrician/gynaecologist at Brigham and Women’s Hospital, Boston. “It’s always a very personalised discussion. Each woman is different, their exposure to SSRIs are different,” she continued.

The decision to continue or stop treatment for any woman during pregnancy should be one that has been carefully deliberated and thoroughly discussed with patients. The American College of Obstetricians and Gynaecologists (ACOG) outlines that practitioners should essentially weigh the risk to the baby of antidepressant exposure against the risk to the mother of untreated depression in each individual situation. MIMS

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