BackgroundUnintended pregnancies can have adverse physical, mental, social, and economic outcomes. Illegal abortions and associated complications often follow unintended pregnancies and claim the lives of many women in developing countries. To better understand how unintended pregnancy impacts married women, this study aimed to assess the prevalence of unintended pregnancies and associated factors among married pregnant women in West Belessa woreda, Ethiopia.MethodsA community-based cross-sectional study was conducted from August to September 2015.. A multistage stratified sampling technique was used to select nine kebeles, to participate in the study. A total of 619 married pregnant women were selected from these kebeles by the simple random sampling technique and data were collected with a structured questionnaire. Binary logistic regression analysis was used to identify factors associated with the unintended pregnancies. A p-value of < 0.05 in the multi-variable model was used to identify significance.ResultA total of 592 married pregnant women were surveyed regarding their intention to become pregnant. The prevalence of unintended pregnancy was 13.7%. Age at pregnancy (AOR: 15.2, 95% CI (1.9, 125.2)), history of stillbirth (AOR: 3.3, 95% CI (1.4, 7.9)), discussing pregnancy related issues with husbands (AOR: 2.3, 95% CI (1.1, 5.0)), making family planning decisions on their own (AOR: 0.4, (0.2, 0.8)), and making family planning decisions with their husbands (AOR: 95% CI 0.2 (0.1, 0.4)) were significantly associated with unintended pregnancies in this group.ConclusionThe magnitude of unintended pregnancy in the study area was low. Age at pregnancy, history of stillbirth and involvement of partners in making reproductive health choices were associated with unintended pregnancies. Empowering women to make family planning decisions and increasing partner involvement in reproductive health could decrease unintended pregnancies.