Prenatal antidepressant use and risk of congenital malformations: A population-based cohort study.

Previous studies examining antidepressants and congenital-malformations were primarily conducted in western countries, and many were constrained by important methodological limitations. This population-based study identified 465,069 women (including 1,705 redeemed ≥1 prescription of antidepressants during first-trimester) aged 15-50 years who delivered their first and singleton child between 2003 and 2018 in a predominantly-Chinese population in Hong Kong, using territory-wide medical-record database of public-healthcare services, and employed propensity-score fine-stratification-weighted logistic-regression analyses to evaluate risk of any major and organ/system-specific congenital-malformations following first-trimester exposure to antidepressants. Major malformation overall was not associated with any antidepressant (weighted-odds-ratio wOR, 0.88 [95 %CI, 0.44-1.76]), specific drug-class, or individual antidepressants. Exposure to any antidepressant was associated with increased risk of cardiac (wOR, 1.82 [95 %CI, 1.07-3.12]) and respiratory anomalies (wOR,4.11 [95 %CI, 1.61-10.45]). Exposure to selective-serotonin-reuptake-inhibitors (SSRI) and multiple-AD-classes were associated with respiratory and cardiac anomalies, respectively. However, these identified associations were not consistently affirmed across sensitivity analyses, precluding firm conclusion. Observed associations of specific cardiac defects with serotonin-norepinephrine-reuptake-inhibitors (SNRI), tricyclic-antidepressants (TCA) and multiple-AD-classes were noted with wide confidence-intervals, suggesting imprecise estimation. Overall, our findings suggest that first-trimester antidepressant exposure was not robustly associated with increased risk of congenital-malformations. Further research clarifying comparative safety of individual antidepressants on specific malformations is warranted.