To determine the receptivity of prenatal care providers and their patients to carrier testing for cystic fibrosis (CF), we offered free carrier screening, followed by genetic counseling of carriers, to all prenatal care providers in Rochester, NY, for all their female patients of reproductive age, pregnant or not. Of 124 prenatal care providers, only 37 elected to participate, but many of these offered screening only to pregnant women. The acceptance rate among pregnant women was approximately 57%. The most common reasons for accepting screening were to obtain reassurance (50.7%) and to avoid having a child with CF (27.8 %). The most common reasons for declining screening were not intending to terminate a pregnancy for CF (32.4%) and believing that the chance of having a CF child was very low (32.2%). Compared with decliners, acceptors were more likely to have no children, regarded having a child with CF as more serious, believed themselves more susceptible to having such a child, knew more about CF, would be more likely to terminate a pregnancy if the fetus were shown to have CF, and more strongly supported offering CF screening to women of reproductive age. Of 4,879 women on whom results were obtained, 124 were found to be carriers. Of these 124 carriers, the partners of 106 were tested. Of the five at-risk couples, four requested prenatal diagnosis and one requested neonatal diagnosis. No woman found to be a carrier whose partner tested negative requested prenatal diagnosis. Except for the imperfect knowledge of those testing negative, none of the adverse outcomes predicted for CF carrier testing in the general population were observed in this study.