Association between antipsychotic use in pregnancy and the risk of gestational diabetes: Population-based cohort studies from the United Kingdom and Hong Kong and an updated meta-analysis

Aims: To investigate whether exposure to antipsychotic medications during pregnancy is associated with gestational diabetes mellitus (GDM) in United Kingdom (UK) and Hong Kong (HK) population cohorts.

Methods: Two population-based cohort studies were conducted using data from the UK The Health Improvement Network (THIN) and HK Clinical Data Analysis and Reporting System (CDARS). Nondiabetic women who received any type of antipsychotic medicine before their first pregnancy were included in our cohorts. The exposed group comprised women who continued using antipsychotics from the start of pregnancy to delivery (continuers), while the comparison group included women who were prescribed antipsychotics before the start of pregnancy but stopped during pregnancy (discontinuers). GDM was identified using GDM diagnosis and/or clinicians reported GDM. Odds ratios (ORs) with a 95% confidence interval (CI) were calculated to assess the association between antipsychotic use during pregnancy and GDM. Propensity Score fine-stratification weighting was used to adjust for potential confounding factors.

Results: 3114 women with registered first pregnancies (2351 in THIN and 763 in CDARS) were included. 5.49% (2.55% in THIN and 14.55% in CDARS) were diagnosed with GDM. The adjusted OR of GDM in continuers was 0.73 (95% CI: 0.43-1.25) in THIN and 1.16 (95% CI: 0.78-1.73) in CDARS compared with discontinuers.

Conclusions: Our results do not suggest an increased risk of GDM in women who continued using antipsychotics during pregnancy compared to women who stopped. Based on these results, women should not stop their regular antipsychotics prescriptions in pregnancy due to the fear of GDM.