Cost-effectiveness of self-injected DMPA-SC compared with health-worker-injected DMPA-IM in Senegal

Objectives

To evaluate the cost-effectiveness of self-injected subcutaneous depot medroxyprogesterone acetate (DMPA-SC) compared to health-worker-administered intramuscular DMPA (DMPA-IM) in Senegal and to assess how including practice or demonstration injections in client self-injection training affects estimates.

Study design

We developed a decision-tree model with a 12-month time horizon for a hypothetical cohort of 100,000 injectable contraceptive users in Senegal. We used the model to estimate incremental costs per disability-adjusted life year (DALY) averted. The analysis derived model inputs from DMPA-SC self-injection continuation and costing research studies and peer-reviewed literature. We evaluated the cost-effectiveness from societal and health system perspectives and conducted one-way and probabilistic sensitivity analyses to test the robustness of results.

Results

Compared to health-worker-administered DMPA-IM, self-injected DMPA-SC could prevent 1402 additional unintended pregnancies and avert 204 maternal DALYs per year for this hypothetical cohort. From a societal perspective, self-injection costs less than health worker administration regardless of the training approach and is therefore dominant. From the health system perspective, self-injection is dominant compared to health worker administration if a one-page instruction sheet is used and one additional DMPA-SC unit is used for training and is cost-effective at $208 per DALY averted when two additional DMPA-SC units are used. Sensitivity analysis showed estimates were robust.

Conclusions

Self-injected DMPA-SC averted more pregnancies and DALYs and cost less from the societal perspective compared to health-worker-administered DMPA-IM and hence is dominant. Using fewer DMPA-SC units for practice or demonstration improves cost-effectiveness of self-injection from the health system perspective.

Implications

Evidence from Senegal shows that self-injection of DMPA-SC can be dominant or cost-effective from both health system and societal perspectives relative to DMPA-IM from health workers even if women practice injecting or health workers demonstrate with one or two DMPA-SC units. Evidence on whether practice or demonstration is required for client training would be useful.