RT Journal Article SR Electronic T1 Antipsychotic use in pregnancy and risk of attention/deficit-hyperactivity disorder and autism spectrum disorder: a Nordic cohort study JF Evidence Based Mental Health JO Evid Based Ment Health FD BMJ Publishing Group Ltd, Royal College of Psychiatrists and British Psychological Society SP 54 OP 62 DO 10.1136/ebmental-2021-300311 VO 25 IS 2 A1 Hálfdánarson, Óskar A1 Cohen, Jacqueline M A1 Karlstad, Øystein A1 Cesta, Carolyn E A1 Bjørk, Marte-Helene A1 Håberg, Siri Eldevik A1 Einarsdóttir, Kristjana A1 Furu, Kari A1 Gissler, Mika A1 Hjellvik, Vidar A1 Kieler, Helle A1 Leinonen, Maarit K A1 Nørgaard, Mette A1 Öztürk Essen, Buket A1 Ulrichsen, Sinna Pilgaard A1 Reutfors, Johan A1 Zoega, Helga YR 2022 UL http://ebmh.bmj.com/content/25/2/54.abstract AB Background Antipsychotics are increasingly used among women of childbearing age and during pregnancy.Objective To determine whether children exposed to antipsychotics in utero are at increased risk of attention-deficit/hyperactivity disorder (ADHD) or autism spectrum disorder (ASD), accounting for maternal diagnoses of bipolar, psychotic and other psychiatric disorders. Design Population-based cohort study, including a sibling analysis. Setting Nationwide data on all pregnant women and their live-born singletons in Denmark (1997-2017), Finland (1996-2016), Iceland (2004-2017), Norway (2004-2017), and Sweden (2006-2016). Participants 4 324 086 children were eligible for inclusion to the study cohort. Intervention Antipsychotic exposure in utero, assessed by pregnancy trimester, type of antipsychotic, and varying patterns of use. Main outcome measures Non-mutually exclusive diagnoses of ADHD and ASD. We used Cox proportional hazard models to calculate hazard ratios (HRs) controlling for maternal psychiatric disorders and other potential confounding factors.Findings Among 4 324 086 singleton births, 15 466 (0.4%) were exposed to antipsychotics in utero. During a median follow-up of 10 years, we identified 72 257 children with ADHD and 38 674 children with ASD. Unadjusted HRs were raised for both outcomes but shifted substantially towards the null after adjustment; 1.10 (95%CI 1.00 to 1.27) for ADHD and 1.12 (0.97 to 1.29) for ASD. Adjusted HRs remained consistent by trimester of exposure and type of antipsychotic. Comparing in utero exposure with pre-pregnancy use yielded HRs of 0.74 (0.62 to 0.87) for ADHD and 0.88 (0.70 to 1.10) for ASD. Sibling analyses yielded HRs of 1.14 (0.79 to 1.64) for ADHD and 1.34 (0.75 to 2.39) for ASD.Discussion Our findings suggest little or no increased risk of child ADHD or ASD after in utero exposure to antipsychotics.Clinical implications Results regarding child neurodevelopment are reassuring for women who need antipsychotics during pregnancy.No data are available. No additional data available.