A decision analysis model of 1-year effectiveness of intended postplacental compared with intended delayed postpartum intrauterine device insertion

OBJECTIVE: To compare, using decision analysis methodology, the 1-year probability of pregnancy after intended postplacental intrauterine device (IUD) insertion with intended delayed insertion at an outpatient postpartum visit (delayed postpartum placement). METHODS: We developed an evidence-based decision model with the primary outcome of 1-year probability of pregnancy. We compared 1-year probability of pregnancy after intended postplacental or intended delayed postpartum IUD placement. We obtained estimates from the literature for the proportions of the following: mode of delivery, successful IUD placement, IUD type, postpartum visit attendance, IUD expulsion, IUD discontinuation, and contraceptive use, choice, and efficacy after IUD discontinuation. We performed sensitivity analyses and a Monte Carlo simulation to account for variations in proportion estimates. RESULTS: One-year probabilities of pregnancy among a theoretical cohort of 2,500,000 women intending to receive a postplacental IUD after vaginal birth and 1,250,000 women intending to receive a postplacental IUD after cesarean birth were 17.3% and 11.2%, respectively; the 1-year probability of pregnancy among a theoretical cohort of 2,500,000 women intending to receive a delayed postpartum IUD was 24.6%. For delayed postpartum IUD placement to have effectiveness equal to postplacental placement, 91.4% of women delivering vaginally and 99.7% of women delivering by cesarean would need to attend postpartum care. Once placed, the effectiveness of postplacental IUDs was lower than that of delayed postpartum IUDs: 1-year probabilities of pregnancy after IUD placement at a vaginal birth, cesarean birth, and an outpatient postpartum visit were 15.4%, 6.6%, and 3.9%, respectively. CONCLUSION: After accounting for factors that affect successful IUD placement and retention, this decision model indicates that intended postplacental IUD insertion results in a lower 1-year probability of pregnancy as compared with intended delayed postpartum IUD insertion.