OBJECTIVE Late recognition of pregnancy and unintended pregnancy has been associated with adverse pregnancy outcomes such as preterm birth, low birth weight, and admission to neonatal care. This study examined the factors associated with late recognition of pregnancy among women reporting unintended pregnancy. DESIGN AND SAMPLE A secondary analysis of a population-based survey, the Pregnancy Risk Assessment Monitoring System of the United States. A total of 143,303 women of childbearing age. Analyses included descriptive statistics and multivariate analysis using logistic regression. RESULTS Exactly, 42.4% described their pregnancies as unintended and 28.3% recognized their pregnancies late. Women with unintended pregnancy took longer, 7.2 weeks (99% CI = 7.07-7.24) to recognize their pregnancies compared to 5.2 weeks (99% CI = 5.18-5.27) for women with intended pregnancy. Late recognition of pregnancy was significantly higher among women who were not married (adjusted odds ratio [AOR] = 1.29, p < .01), had more arguments with their partners (AOR = 1.08, p < .01), were smokers (AOR = 1.15, p < .01), and belonged to an ethnic minority group. CONCLUSIONS Public health nurses and other health professionals can promote early recognition of pregnancy among women who are not married, belong to ethnic minority groups, or have more arguments with their husbands or partners.