Background: Previous literature suggests a positive association between history of premenstrual syndrome (PMS) and development of postpartum depression (PPD); however, limited evidence has come from prospective population-based studies and whether history of depression affects this association is unknown.
Methods: This study included 5479 women from the 1973-78 cohort of the Australian Longitudinal Study on Women's Health and estimated the association between pre-pregnancy PMS and PPD. Participants were followed from 22-27 years in 2000 to 37-42 years in 2015. PMS was collected from a 4-category Likert-scale reporting on frequency of PMS in the last 12 months (never, rarely, sometimes, or often) at the survey preceding an index birth. PPD was ascertained from reports of doctor diagnoses for each birth. Relative risks (RRs) and 95% confidence intervals (CIs) were used to estimate the association of interest. The role of history of depression was assessed by testing its interaction with pre-pregnancy PMS.
Results: During 15 years’ follow-up, 15.4% of participating women reported PPD; and 55.1% reported PMS (rarely: 17.2%, sometimes: 25.7%, and often: 12.2%). Compared to women who had no PMS before pregnancy, those who rarely had PMS had similar risk of PPD (1.03, 0.82-1.30); whereas those who sometimes or often had PMS had significantly higher risk of PPD (1.31, 1.09-1.57 and 1.51, 1.22-1.87, respectively). History of depression did not affect the association.
Limitations: PMS was self-reported. PMS severity was not collected. Conclusions: This large population-based study provides evidence of a dose-response relationship between PMS prior to pregnancy and PPD, independent of history of depression. Evidence to date suggests PMS has the potential to help identify women at increased risk of PPD before pregnancy.