Postpartum haemorrhage and risk of mental ill health: A population-based longitudinal study using linked primary and secondary care databases.

There is a gap in the literature investigating the impact of obstetric complications on subsequent mental ill health outcomes. The aim of this study was to establish the association between post-partum haemorrhage (PPH) and mental ill health. We conducted a retrospective open cohort study utilizing linked primary care (The Health Improvement Network (THIN)) and English secondary care (Hospital Episode Statistics (HES)) databases, from January 1, 1990 to January 31, 2018. A total of 42,327 women were included: 14,109 of them were exposed to PPH during the study period and 28,218 unexposed controls were matched for age and date of delivery. Hazard ratios (HRs) for mental illness among women with and without exposure to PPH were estimated after controlling for covariates. Women who had had PPH were at an increased risk of developing postnatal depression (adjusted HR: 1·10, 95%CI: 1·01-1·21) and post-traumatic stress disorder (PTSD) (adjusted HR: 1·17, 95%CI: 0·73-1·89) compared to women unexposed to PPH. When restricting the follow-up to the first year after childbirth, the adjusted HR for PTSD was 3·44 (95% CI 1·31-9·03). No increase in the overall risk was observed for other mental illnesses, including depression (adjusted HR: 0·94, 95%CI: 0·87-1·01), severe mental illness (adjusted HR: 0·65, 95%CI: 0·40-1·08, p = 0·239) and anxiety (adjusted HR: 0·99, 95%CI: 0·90-1·09). PPH is associated with a significant increase in the risk of developing postnatal depression and PTSD in the first year after delivery. Active monitoring for mental illness should form an integral part of the follow-up in women who suffered a PPH.