Global Prevalence of Obstetric Causes of Critical Illness in Pregnancy: A Systematic Review and Meta-Analysis

OBJECTIVES: To determine the prevalence, risks, and outcomes of obstetric causes of critically ill pregnant women admitted to the ICU. DATA SOURCES: We searched the PubMed, Scopus, Embase, Ovid, and ScienceDirect databases up to May 15, 2026. STUDY SELECTION: We included studies reporting primary data on critically ill pregnant and postpartum women (up to 48 d post-delivery) admitted to an ICU, with relevant obstetric risk factors and maternal outcomes. DATA EXTRACTION: Two reviewers independently performed data extraction and risk-of-bias assessment using the adapted Newcastle-Ottawa Scale. The pooled prevalence was estimated using a random-effects model with 95% CIs. DATA SYNTHESIS: Of the 3,735 total records, 50 studies met the eligibility criteria, encompassing 7,756,232 women receiving obstetric care in tertiary hospitals across 20 countries, with 49,299 ICU admissions. Globally, 1.0% (95% CI, 0.8-1.3%) of pregnant and postpartum women experience critical illness and require admission to an ICU. The frequency varies according to the country's income levels, with the highest in low-income countries (4.1%) and the lowest in high-income countries (0.5%). Notably, 72.3% of ICU admissions were attributed to known obstetric causes, primarily obstetric hemorrhage (23.3%) and hypertension in pregnancy (26.9%). Nearly 33.3% of ICU patients required either respiratory or transfusion support, and the maternal mortality rate among ICU-admitted obstetric women was 8.5%. CONCLUSIONS: Nearly one in 100 pregnancies require admission to intensive care due to critical illness, and nearly three-quarters of these admissions were due to direct obstetric causes, with high maternal morbidity and mortality. Obstetric hemorrhage and hypertensive disorders account for the majority of ICU admissions. Strengthening obstetric care in resource-limited settings through the expansion and optimization of intensive care services is essential for improving maternal and neonatal outcomes and reducing preventable morbidity and mortality.