Effects of the Momentum project on postpartum family planning norms and behaviors among married and unmarried adolescent and young first-time mothers in Kinshasa: A quasi-experimental study

This study evaluated the effect of Momentum–an integrated family planning, maternal and newborn health, and nutrition intervention–on postpartum family planning norms and behaviors among ever married and never-married first-time mothers age 15–24 in Kinshasa, Democratic Republic of the Congo. Using data collected in 2018 and 2020, we conducted an intent-to-treat analysis among 1,927 first-time mothers who were about six-months pregnant at enrollment. Difference-in-differences models were run for panel data and treatment effects models with inverse-probability weighting for endline-only outcomes. Average treatment effects (ATE) were estimated. Momentum had positive effects on partner discussion of family planning in the early postpartum period (ever married 15–19: ATE = 0.179, 95% CI = 0.098, 0.261; never married 15–19: ATE = 0.131, 95% CI = 0.029, 0.232; ever married 20–24: ATE = 0.233, 95% CI = 0.164, 0.302; never married 20–24: ATE = 0.241, 95% CI = 0.121, 0.362) and discussion with a health worker, and on obtaining a contraceptive method in the early postpartum period, except among never married adolescents. Among adolescents, intervention effects on modern contraceptive use within 12 months of childbirth/pregnancy loss were larger for the never married (ATE = 0.251, 95% CI = 0.122, 0.380) than the ever married (ATE = 0.114, 95% CI = 0.020, 0.208). Full intervention exposure had consistently larger effects on contraceptive behaviors than partial exposure, except among ever married adolescents. Momentum had no effect on normative expectations about postpartum family planning use among adolescents, and on descriptive norms and personal agency among those who were never married. Results for normative outcomes and personal agency underscored the intersectionality between young maternal age and marital status. Future programs should improve personal agency and foster normative change in support of postpartum family planning uptake and tailor interventions to different age and marital status subsets of first-time mothers.