BACKGROUND: Unintended pregnancies may carry serious consequences for women and their families, including the possibility of unsafe abortion, delayed prenatal care, poor maternal mental health and poor child health outcomes. Although between 1993 and 2008, unintended births decreased from 42% to 37% in Ghana, the rate of decline is low, whilst levels are still very high. This raises the need to understand factors associated with unintended pregnancies, especially among women in rural settings where the rates and risks are highest to help improve maternal health. METHOD: We collected data from 1,914 pregnant women attending antenatal clinic between January 2012 and April 2012 in four health facilities in the Mfantseman Municipal of the Central Region of Ghana. We used bivariate and multivariate logistic regression analyses to explore how socio-demographic characteristics, past reproductive health experiences, partner characteristics and relations, awareness and past experience with contraceptives, influenced the status of women's current pregnancy (whether intended or unintended). RESULTS: The mean age of the 1,914 respondents in this study was 25.6 ± 6.5 years. Seventy percent (70%) said the pregnancies they were carrying were unintended. The odds of carrying unintended pregnancy among women with five or more children were higher than those with one to two children [AOR 6.06, 95% CI (3.24-11.38) versus AOR 1.48, 95% CI (1.14-1.93)]. Women with other marital arrangements showed significantly higher odds of carrying unintended pregnancy compared to those married by ordinance (Muslim or Christian wedding). Women not living with their partners exhibited increased odds of having unintended pregnancies compared to women who lived with their partners (AOR 1.72, 95% CI: 1.28 - 2.30). Awareness of traditional methods of family planning (withdrawal and rhythm) was associated with lower odds of having unintended pregnancy compared to non-awareness (AOR 0.66, 95% CI (0.49-0.89). CONCLUSIONS: In this study, important risk factors associated with unintended pregnancies were: parity, living arrangements with partner, marriage by ordinance and awareness of traditional, non-pharmacological contraceptive methods. Family planning interventions targeting different groups of women, especially during the postpartum period, would be essential to reduce rates of unintended pregnancies and promote positive health outcomes.