The relationship between severe maternal morbidity and psychological health symptoms at 6–8 weeks postpartum: a prospective cohort study in one English maternity unit

BACKGROUND The incidence of severe maternal morbidity is increasing in high-income countries. However, little has been known about the impact on postnatal morbidity, particularly on psychological health outcomes. The objective of this study was to assess the relationship between severe maternal morbidity (ie. major obstetric haemorrhage, severe hypertensive disorders or intensive care unit/obstetric high dependency unit admission) and postnatal psychological health symptoms, focusing on post-traumatic stress disorder (PTSD) symptoms at 6-8 weeks postpartum. METHOD A prospective cohort study was undertaken of women who gave birth over six months in 2010 in an inner city maternity unit in England. Primary outcomes were prevalence of PTSD symptoms namely: 1) intrusion and 2) avoidance as measured using the Impact of Event Scale at 6 - 8 weeks postpartum via a self-administered postal questionnaire. Secondary outcomes included probable depression. Data on incidence of severe maternal morbidity were extracted from maternity records. Multivariable logistic regression analysis examined the relationship between severe maternal morbidity and PTSD symptoms taking into account factors that might influence the relationship. RESULTS Of women eligible to participate (n=3509), 52% responded. Prevalence of a clinically significant level of intrusion and avoidance were 6.4% (n=114) and 8.4% (n=150) respectively. There was a higher risk of PTSD symptoms among women who experienced severe maternal morbidity compared with women who did not (adjusted OR = 2.11, 95%CI = 1.17-3.78 for intrusion; adjusted OR = 3.28, 95%CI = 2.01-5.36 for avoidance). Higher ratings of reported sense of control during labour/birth partially mediated the risk of PTSD symptoms. There were no statistically significant differences in the prevalence or severity of symptoms of depression. CONCLUSION This is one of the largest studies to date of PTSD symptoms among women who had recently given birth. Findings showed that an experience of severe maternal morbidity was independently associated with symptoms of PTSD. Individually tailored care that increases women's sense of control during labour may be a protective factor with further work required to promote effective interventions to prevent these symptoms. Findings have important implications for women's health and the content and organisation of maternity services during and after the birth.