Introduction and general principles

Up to 20% of women will experience a mental health problem during pregnancy or in the first year after birth.1 The impact can be widespread affecting not only the woman but also her partner and their children. The economic impact of mental illness for a 1-year cohort of births in the UK is over £8 billion.2 Women may enter pregnancy with an existing mental health diagnosis, for others illness can develop for the first time during pregnancy or in the postpartum period. Many women will benefit from psychological interventions and certainly for women with mild to moderate illness this should be the first-line therapeutic intervention.3 Some women will be taking psychotropic medication prior to pregnancy and ideally, they would have received preconception care in order to optimise and stabilise their medication and their condition prior to conception. The preconception consultation should also take the opportunity to share general advice for women such as optimising their body mass index (BMI), stopping smoking and starting folic acid supplementation. For more details on general prepregnancy care, please refer to the first article in this series (Girling J. Prescribing for pregnancy: general prepregnancy care. DTB 2019;57:168–72).4

When a pharmacological intervention is required in pregnancy, the aim should always be …