Association Between the Anemia During Pregnancy and Maternal Intensive Care Unit Admissions: A Systematic Review and Meta-Analysis

Anemia during pregnancy is one of the most common conditions that may have adverse consequences on maternal and fetal health. Current evidence is inconsistent with regards to the effects of anemia on maternal ICU admissions. This meta-analysis aimed to examine the overall effect of anemia during pregnancy on maternal ICU admissions. We searched PubMed, Embase, Cochrane Library, and Web of Science for observational studies that compared the risk of ICU admission between anemic and non-anemic pregnant women. We pooled the odds ratios (ORs) for ICU admission using a random-effects model. Heterogeneity among studies was assessed using prediction intervals (PIs), Tau² and I² statistics. Sensitivity analysis by excluding outlier studies, meta-regression by sample size and age, and publication bias detection by LFK index and Doi plot was undertaken. Eight studies with a total of 21,997,574 participants in both anemic and non-anemic groups were included. Of them, meta-analysis was conducted in seven studies which yielded a pooled OR for anemia and ICU admission as 1.32 (95% CI 0.62–2.81). There was also a very high level of heterogeneity among studies (PI: 0.10–18.16, I² = 100%). When an influential study was omitted, the pooled OR 1.16 (95% CI − 1.13; 1.20) for ICU admission was significant. The LFK index was − 3.64, indicating publication bias. Anemia in pregnant women might be associated with a higher risk of ICU admission, but it is essential to interpret this cautiously due to significant heterogeneity and potential publication bias.

Registration: PROSPERO database (CRD42023466529).