BACKGROUND:
Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed for moderate to severe depression during pregnancy, yet their impact on maternal and neonatal outcomes remains insufficiently studied.

OBJECTIVES:
The study aimed to describe the prevalence of prescribed SSRIs to pregnant women and its association with birth outcomes after a vaginal birth.

METHODS:
Methods A national register-based population study. The study included 405,936 term vaginal births in Sweden. SSRI prescriptions within three months before the due date were identified. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated, with statistical significance set at p<0.001.

RESULTS:
SSRIs were prescribed to 6374 women (1.6%), with prevalence rising from 0.3% to 2.6% over the study period (2005-2015). SSRI use was associated with higher rates of labour induction (AOR 1.27; 95% CI 1.18–1.36), epidural anaesthesia (AOR 1.63; 1.54–1.73), and postpartum hemorrhage >1.000 ml. (AOR 1.41; 1.31–1.51). Women prescribed SSRIs were more likely to give birth at 37–38 weeks gestation (AOR 1.79; 1.68–1.90), have neonates with head circumference <35 cm (AOR 1.49; 1.41–1.59), and have neonates with Apgar score <7 at 5 minutes (AOR 4.78; 4.03–5.67). Neonates were less likely to have a birth weight ≥4.500 g (AOR 0.73; 0.52–0.85).

CONCLUSIONS:
SSRI prescriptions during pregnancy increased significantly between 2005 and 2015. Use was associated with higher risks of several adverse maternal and neonatal outcomes, such as induction of labour, and postpartum hemorrhage ≥ 1000 mL, Apgar score <7 at 5 minutes, and smaller head circumference. Results underscore the need for evidence-based decision-making, careful monitoring, and proactive multidisciplinary support for pregnant women with mental ill-health concerns.

KEY MESSAGE:
SSRI prescriptions during pregnancy was associated with higher risks of several adverse maternal and neonatal outcome Poster session 2 (Group A)