To describe characteristics of women without prenatal care and their reasons for not seeking prenatal care. Retrospective record review. Urban, academic medical center. Women without prenatal care whose pregnancies reached the third trimester, who presented to the hospital for delivery or immediately postpartum for a 7 year period. Records were reviewed for factors including socio-demographic factors, history of pregnancy/miscarriage/abortion, social supports, abuse history, history of substance use, toxicology results, history of mental illness or mental retardation, and the reason for lack of prenatal care. Among 211 women with no prenatal care, the primary reasons were noted: 30% had problems with substance use; 29% experienced denial of pregnancy; 18% had financial reasons; 9% concealed pregnancy; and 6% believed they did not need prenatal care due to multiparity. Women with substance use disorders were significantly more likely to be older, unemployed multigravidas. Nurses should target specific groups of women for education and intervention based on their rationale for not seeking prenatal care.