To determine individual and delivery characteristics of women least likely to obtain a requested postpartum tubal ligation (PPTL) and, secondarily, to compare the postpartum contraceptive choices of women with an unfulfilled sterilization request to women not requesting a PPTL. Record review ofwomen delivering a liveborn singleton between December 2007 and May 2008 at the University of Texas San Antonio. Primary outcomes were risk factors for not receiving a requested PPTL. Secondary outcome was to compare the postpartum contraceptive choices of women not receiving a PPTL to controls, women not requesting a PPTL. During the observation period, 429 of 1,460 women requested a PPTL; 296 (69%) received the procedure, and 133 (31%) did not. The majority of patients (332/429, 77.4%) were Hispanic. Pretest power analysis concluded that 107 women were required in each group. Cesarean delivery was associated with the highest likelihood of receiving a PPTL. Women receiving a PPTL were more likely (p < or = 0.05) to be a documented U.S. resident, married, of lower parity, have private or any medical insurance and to have received any prenatal care. Postpartum contraception among women with unfulfilled sterilization requests was similar to that among controls. Although financial and policy barriers exist, the majority of patients requesting a PPTL received the procedure.