Goals 3 and 5 of the United Nations Sustainable Development Goals are to promote good health and well-being and to achieve gender equality, respectively. To successfully move toward these goals in the area of gender equality, there is the need to understand the underlying legislative or laws that protect women and girls from all forms of domestic violence (DV), including gender-based violence (GBV). The cardinal objective of this study, therefore, was to examine the risk factors of GBV and the physiological effects of GBV. To date, few studies have quantified the relationship between laws on DV and the incidence of DV/GBV. This article fills that gap by using Demographic and Health Surveys (DHS) data of 12 African countries. We applied multivariate logistic regression to estimate the association of the absence of laws on DV, men dominant power, history of violence, alcohol consumption, women’s attitude toward men’s violence perpetration, and decision-making power with the scores of GBV and physiological effects of GBV. Group Kruskal–Wallis Rank test was used to determine the variation of the two outcomes among the 12 countries. Results show significant disparities in the score of GBV, H test (11) = 168,217, p < .001, and score of physiological effects, H test (11) = 122,127, p < .001, among the 12 countries. Specifically, Ghana, Namibia, Rwanda, Mozambique, Zimbabwe, Malawi, Sierra Leone, and Togo reported the highest physiological effect of GBV. Presence of DV laws, male dominance, alcohol consumption, history of abuse, and women empowerment predict GBV and the physiological effect of GBV. Thus, building strong legal frameworks against all forms of DV and empowering women may reduce the incidence of GBV and physiological effects of GBV for all African women.