Unintended pregnancy among military women influences their lives and has implications for troop readiness and deployment. The purpose of this study was to identify the prevalence of unintended pregnancy in the US Army and assess the variables associated with unintended pregnancy. Using a cross-sectional design, 212 female soldiers who delivered viable infants at Darnall Army Community Hospital, Fort Hood, Texas from 1 June 1998 to 6 October 1998 completed a self-administered survey on pregnancy intention and sociodemographic factors. Approximately 35% of the infants were intended, 51% were unintended and 14% were ambivalent, resulting in 65% not intended, a rate consistent with the upper level of civilian communities. Factors associated univariably with unintended pregnancy included being unmarried, being in the lower enlisted rank, having less than a college degree, and living in the barracks. This study shows the importance of developing programmes and policies that address pregnancy among military personnel.