We conduct a randomized control trial that improves pregnant and immediate postpartum women's access to family planning, including counseling, free transport to a clinic, and reimbursement for family planning services over a two-year period. We study the effects of our intervention on child growth and development. We study 720 children born to participating women and find that children born to mothers assigned to the intervention arm were 0.23-0.25 SD taller for their age and were 6.7-6.9 percent less likely to be stunted within a year of exposure to the intervention. We find that children born to mothers assigned to the intervention scored 0.1 SD higher on a caregiver reported measure of cognitive development after two years of intervention exposure. Using a causal mediation analysis, we show that 25 percent of the effects on heights and 30 percent of the effects on cognition can be explained by increases in healthcare use.