Objective: Effective postpartum contraception helps space births and reduce unintended pregnancy. We explore predictors, including trust, of choosing effective postpartum contraception among a cohort of pregnant women. Methods: This prospective, observational study enrolled adult English-speaking pregnant women during prenatal care. We administered surveys at enrollment and prior to discharge. Our primary predictor was trust in the health care system measured by a validated scale (possible score 17-85) and treated as both a continuous and dichotomous (high/low) variable. Our primary outcome was a dichotomous choice of any moderately/ highly effective method versus less effective/no method. Statistical analysis was performed using Chi-square tests, ttest, and logistic regression using SAS 9.2. Results: 249 enrolled and 215 completed postpartum surveys. 30% chose long acting reversible contraception (LARC) postpartum compared to 16% female sterilization, 4% male sterilization, 27% moderately effective methods, and 23% less effective methods/none. Mean trust scores were 66.0 for moderately/highly effective methods versus 63.9 for less effective/no method. (p=0.09) In a model including race, pregnancy intendedness, and trust, participants with higher trust (AOR 1.96, 95% CI 0.98, 3.94) and Black participants (AOR 2.6, 95% CI 1.17, 5.76) were more likely to choose effective contraception while those with intended pregnancies were 66% less likely to choose effective contraception (95% CI 0.16, 0.72). Conclusions: Higher trust, Black race, and unintended pregnancy are associated with choice of more effective contraception postpartum. Targeted messaging for other groups may improve adoption of more effective postpartum contraception and improve birth spacing.