The main objective of this paper was to identify HIV risk factors at the individual, partner, and partnership levels among married, lifetime monogamous women in a nationally representative sample of Zimbabweans aged 15-29 years. Cross-sectional data were collected through individual survey interviews among 1,286 women who provided blood for HIV testing. The HIV prevalence among these women was high (21.8%). HIV risk increased with female age, within-couple age difference of more than 5 years, the husband having children with other women, and the respondent being 'extremely likely' to discuss monogamy in the next 3 months with her husband. The latter suggests that women were attempting to communicate their concerns while unaware that they were already HIV positive. HIV risk largely appears related to the partner's past and present sexual behavior, resulting in limited ability for married women to protect themselves from infection. Overall, lifetime monogamy offers insufficient protection for women.