Postpartum Depression and Environmental Factors

IGEDEPP is a prospective cohort of 3310 Caucasian women who gave birth in eight maternity departments in the Paris metropolitan area in France, between November 2011 and June 2016. The women included in this cohort were aged over 18, Caucasian, French speaking, and were covered by French social insurance (which concerns any person who works or resides in France in a stable and regular manner is a public health insurance system that covers all life risks including health and maternity). The sample was restricted to Caucasian women to ensure ethnic homogeneity for genetic studies. 

The researchers of this study conducted their research using a cohort of adult, Caucasian, French women who gave birth during a set period of time in Paris.

Based on a large prospective multicentric cohort of women in the postpartum period, our aims were threefold: (1) to describe the IGEDEPP cohort (Interaction of Gene and Environment of Depression during PostPartum) developed to identify risk factors for PPD, (2) to estimate the cumulative incidence and prevalence of PPD at 8 weeks and one year after delivery, and (3) to estimate the prevalence of lifetime psychiatric disorders (mood, anxiety, eating and substance use disorders and suicide attempts) and the frequency of stressful events during childhood, pregnancy, and postpartum.

The researchers’ goal was to identify postpartum depression risk factors, determine the prevalence of postpartum depression at 8 weeks and one year postpartum, and to estimate the prevalence of  psychiatric disorders and stressful life events.

Participants lost to follow-up were significantly younger (p < 0.05) and less educated (p < 0.05) than those who were not lost to follow-up. Other baseline characteristics were not significantly different among the two groups, including lifetime history of major depressive episode (Supplementary Tables 1 and 2).

Younger participants and those with less education were less likely to continue their participation in this study.

In the first postpartum year, the cumulative incidence of PPD was 18.1%. Early-onset PPD affected 250 women (8.3%), and 304 women had late-onset PPD (12.9%). In a recent systematic review, the incidence of postpartum depression was 12% and ranged from 3.4% to 34% based on six studies assessing PPD up to 6 months postpartum (Shorey et al., 2018). To our knowledge, no study examining the incidence of PPD at one year postpartum, making our results difficult to compare with existing data.

Unlike other studies, this study examined postpartum depression at the one year mark. This made it difficult to compare with existing studies.

Future research could follow up on the effect of postpartum depression on the child’s well-being, and on the future mental health of the mother.

I found the statistical percentages in brackets after the number of participants difficult to read. For example, in section 3.1 “Among the 3015 women assessed at 8 weeks postpartum, 250 (8.3%, 95%CI 7.3–9.3) met criteria for early-onset PPD,” I did not understand “8.3%, 95%CI 7.3–9.3.”