Despite the growing literature on the impact of Covid-19 on antenatal care (ANC) and maternal/neonatal and child health outcomes globally, substantial knowledge gaps remain about the population-level impact in sub-Saharan Africa (SSA). Existing evidence on the ANC impact of Covid-19 in SSA is largely based on health facility or small-scale qualitative research, which are limited in providing population-level understanding. This paper examines the extent to which Covid-19 impacted ANC service utilisation and identifies what population sub-groups were most adversely impacted. It is based on a secondary analysis of the Madagascar Demographic and Health Survey (DHS), the first DHS in SSA released following the Covid-19 pandemic. Multilevel logistic regression analysis was used to estimate the net effect of Covid-19 on ANC and identify the most at-risk population sub-groups. The findings show that all ANC measures considered (no ANC, early ANC, adequate ANC visits) were significantly affected by Covid-19 (p<0.05). On average, Covid-19 was associated with a 42% increase in the odds of having no ANC, a 22% reduction in the odds of starting early ANC during the first trimester, and a 22% reduction in the odds of receiving adequate ANC (at least four visits, starting during the first trimester). Births to older mothers and to mothers with no education were disproportionately affected during Covid-19. Although youth aged 15–24 had poorer ANC compared to older women before the pandemic, the pattern was reversed during the pandemic. Also, the protective effect of education was stronger during than before the pandemic. These findings underscore the importance of Covid-19 impact mitigation strategies targeting the most at-risk groups (e.g. older mothers). Furthermore, essential information/education during pandemics should be in formats accessible to non-literate women. This paper advances understanding of the population-level impact of Covid-19 on ANC and emphasises the need for further research to better understand the population-level impact of Covid-19 across countries of SSA.