BACKGROUND: Life-threatening maternal near miss (MNM) morbidity can have long-term consequences for the physical, psychological, sexual, social, and economic wellbeing of female individuals. The lifetime risk of MNM (LTR-MNM) quantifies the probability that a female individual aged 15 years will have an MNM before age 50 years, given current mortality and fertility rates. We compare the LTR-MNM globally to reveal inequities in the cumulative burden of severe maternal morbidity across the reproductive life course. METHODS: We estimated the LTR-MNM for 40 countries with multifacility, regional, or national data on the prevalence of MNM morbidity measured using WHO or modified WHO criteria of organ dysfunction from 2010 onwards (Central and Southern Asia=6, Eastern and Southeastern Asia=9, Latin America and the Caribbean=10, Northern Africa and Western Asia=2, sub-Saharan Africa=13). We also calculated the lifetime risk of severe maternal outcome (LTR-SMO) as the lifetime risk of maternal death or MNM. FINDINGS: The LTR-MNM ranges from a 1 in 269 risk in Viet Nam (2010) to 1 in 6 in Guatemala (2016), whereas the LTR-SMO ranges from a 1 in 201 risk in Malaysia (2014) to 1 in 5 in Guatemala (2016). The LTR-MNM is a 1 in 20 risk or higher in nine countries, seven of which are in sub-Saharan Africa. The LTR-SMO is a 1 in 20 risk or higher in 11 countries, eight of which are in sub-Saharan Africa. The relative contribution of the LTR-MNM to the LTR-SMO ranges from 42% in Angola to 99% in Japan. INTERPRETATION: There exist substantial global and regional disparities in the cumulative burden of severe maternal morbidity across the reproductive life course. The LTR-MNM is an important indicator to highlight the magnitude of inequalities in MNM morbidity, once accounting for obstetric risk, fertility rates, and mortality rates. The LTR-SMO can be used to highlight variation in the relative importance of morbidity to the overall burden of maternal ill-health across the female reproductive life course, given countries' stage in the obstetric transition. Both the LTR-MNM and LTR-SMO can serve as important indicators to advocate for further global commitment to end preventable maternal morbidity and mortality. FUNDING: UK Economic and Social Research Council, EU Horizon 2020 Marie Curie Fellowship, and Leverhulme Trust Large Centre Grant.