Timing of depression recurrence in the first year after birth

Background: Women who have suffered from one episode of postpartum-onset major depression (PPMD) experience increased risk for recurrence in the year following another birth. Methods: Non-depressed women (N=51) who had at least one past episode of PPMD were recruited during pregnancy. After birth, subjects were assessed prospectively each week for 20 weeks with the Hamilton Rating Scale for Depression and Research Diagnostic Criteria for recurrence of major depression. Evaluations were carried out at 24, 36, and 52 weeks to assess for episodes beyond 20 weeks postpartum. Results: The data revealed a clustering of cases, with five of the 21 recurrences (24%) occurring in the first 2 weeks. Thirteen of the 21 recurrences (67%) and 19/21 recurrences (90%) occurred in the first 20 and 28 weeks following birth, respectively. Limitations: Although it is unusual for studies of this type to be prospective, the sample size is relatively small. Conclusions: The 1-year recurrence rate was 21/51 or 41%, with a clustering of cases near delivery. All recurrences except two occurred by 28 weeks postpartum.