ObjectiveTo evaluate the effectiveness of incentives for improving compliance with the first prenatal appointment.MethodsOne hundred four low-income women, intending to enroll for prenatal care in a system of Northern California family planning clinics, were recruited for a randomized trial. Study subjects were assigned randomly to one of three groups, receiving a taxicab voucher or a baby-blanket coupon or an appointment slip (Controls). Intention-to-treat analysis was used to compare compliance with the first prenatal appointment between the three groups.ResultsSubjects receiving the taxi voucher had a compliance rate of 82% for the firsgt prenatal appointment, 2% higher than mena appointment compliance in the other groups. The odds ratio for missing the first appointment was 0.32 (95% confidence interval 0.12, 0.88) in the taxi voucher group. This was not affected by controlling for possible confounders. Despite better appointment compliance, only one of 34 taxi vouchers distributed was actually used.ConclusionA taxi voucher incentive was effective in improving compliance with the first prenatal appointment, despite the fact that only one subject actually used the voucher.