The effect of immediate postpartum depot medroxyprogesterone on early breastfeeding cessation.

BACKGROUND This study evaluated the effect of immediate postpartum depot medroxyprogesterone (DMPA) on breastfeeding cessation within 6 weeks postpartum. STUDY DESIGN At low-income-serving obstetric and pediatric clinics, eligible mothers within 1 year postpartum were recruited to participate in a retrospective cohort study. The 183 participants completed a self-administered survey. Surveys were merged with birth certificate data and perinatal maternal/infant medical records. Kaplan-Meier distributions assessed the relationship between DMPA use and breastfeeding cessation. A multivariable Cox proportional hazards model estimated hazard ratios (HRs) and included five known risk factors (age, education, race, parity and parental cohabitation) and identified potential confounders. RESULTS Consistent with the biologic model, the Kaplan-Meier results raised the possibility of a detrimental effect of DMPA on duration of any breastfeeding, but differences in these distributions did not achieve statistical significance (p=.24); after adjustment for potential confounders, this nonstatistically significant association remained (HR: 1.22; confidence interval: 0.75-1.98). CONCLUSION Given the state of the evidence, it is unclear whether a causal effect does or does not exist. However, if there is a causal effect of DMPA on breastfeeding duration, it is minimal. Additional well-designed research is warranted.