Introduction: Intimate partner sexual violence (IPSV) is sexual violence against women by a current or former sexual partner. Sexual violence among pregnant women is higher in low-income countries, particularly in sub-Saharan Africa (SSA), which has numerous negative impacts for both the mother and the growing fetus. There is no recent and distinct information on the magnitude and factors associated with IPSV among pregnant women in SSA. Objective: This study aimed to assess the prevalence of IPSV and its determinants among pregnant women in SSA. Design: A cross-sectional study design using demographic health survey data from 2015 to 2022 in 20 sub-Saharan African countries was used. Methods: The analysis was conducted using a weighted sample of 10,775 women who were pregnant during the survey period (2015–2022). A multilevel logistic regression model was used to identify the determinants of IPSV among pregnant women. The adjusted odds ratio at 95% confidence interval (95% CI) was computed to assess the strength and significance of the association between explanatory and outcome variables. Factors with a p-value of <0.05 are declared statistically significant. Result: In this study, the pooled prevalence of IPSV among pregnant women in SSA was 11.06% (95% CI: 10.48–11.67). Respondents currently working, male-headed households, presence of justified beating, respondent mother’s history of abuse, respondent having no media access, respondent having self-reported sexually transmitted diseases (STIs), partner alcohol use, and residing in East Africa had increased odds of IPSV during pregnancy. On the other hand, nulliparous respondents, respondents involved in healthcare decision-making, households with a high wealth index, and residents of West Africa had decreased odds of IPSV among pregnant women. Conclusion: This study revealed that a significant proportion (11%) of pregnant women experienced intimate partner sexual violence during pregnancy in SSA. Hence, the government, policymakers, and other relevant authorities should give special attention to women’s at-risk of sexual violence, including women who live in households with justified beatings, women with STIs, working women’s, women with drunken partners, and non-autonomous women’s. Prioritization of the east African region, increasing media access, and promoting a healthy lifestyle in the community shall be done to reduce the burden of the problem.