We assessed a prematurity prevention project in a North Carolina region with 21,000 annual births in terms of its impact on low birthweight. Project records were matched to birth certificates in order to compare characteristics of women in and out of the program who received prenatal care from private providers. A logistic regression analysis, in which the effects of race, marital status, age, and other risk factors for low birthweight were statistically controlled, showed that women not in the project were 1.32 times (95% Confidence Interval 1.14, 1.54) as likely as project participants to have a birth under 2500 grams. The relative risk for non-participants for a birth under 1500 grams was 1.87 (95% CI 1.25, 2.80). Strengths and limitations of the study are discussed. The results are consistent with previous work examining the etiologies of low birthweight in private versus public patients.