Critical care admissions and outcomes in pregnant and postpartum women: a systematic review

Purpose

To synthesise evidence for the incidence of intensive care unit (ICU) admission, characteristics and mortality of pregnant and postpartum women with a focus on differences between high-income countries (HICs) and low-middle-income countries (LMICs) and report changes in reported findings since the last review by Pollock et al. (2010).

Methods

We searched Ovid Medline, EMBASE, and CINAHL (2010–2023), following best practice guidelines for abstract screening for large-evidence systematic reviews. Patient and study characteristics of extracted studies were analysed descriptively. Multivariable meta-regression analysis, employing mixed-effects models, was conducted for assessing ICU admission and mortality. Studies reviewed by Pollock et al. were included to perform an overall analysis, including each study period and geographic region in a model.

Results

Seventy-one eligible studies reported data on 111,601 women admitted to ICU, with 41,291,168 deliveries reported in 65 studies. Fifty-six studies were retrospective. Case definitions, admission criteria, and causes of mortality reported were heterogeneous. The pooled ICU admission rate was 1.6% (95% confidence interval [CI] 1.28–1.99; I² = 99.8%), 0.4% (95% CI 0.32–0.48, I² = 99.9%) in HICs versus 2.8% (95% CI 0.65–6.4, I² = 99.9%) in LMICs (p < 0.0001). The pooled ICU mortality rate among 140,780 admissions reported in 63 studies was 6.5% (95% CI 5.2–7.9; I² = 98.7%), with mortality in HICs 1.4% (95% CI 0.8–2.1, I² = 98.04%) lower than LMICs 12.4% (95% CI 8.1–17.5, I² = 98.9%) (p < 0.0001). Multivariable meta-regression analysis found a significant association between the ICU admission rates (p = 0.0001) and mortality (p = 0.0003) with geographic region (HIC vs LMIC). Compared to the earlier study of Pollock et al. in 2010, there was an increase in reported studies (71 vs 40 in Pollock et al. study) and reported admissions (111,601 vs 7887 Pollock et al. study), particularly from LMICs’.

Conclusions

Mortality for critically ill peripartum women is substantial and the gap in reported ICU admissions and mortality for critically ill peripartum women between HIC and LMICs remains unacceptably high. The reports are often small and heterogeneous using many case definitions. Reporting standards focusing on critical care processes and outcomes and large multinational prospective studies are necessary to better understand and mitigate maternal and child health challenges as sustainable development goals in LMICs and HICs.