The following is a summary of “Relationship between maternal anemia and electronic fetal monitoring patterns,” published in the October 2023 issue of Obstetrics and Gynecology by Beermann, et al.

Anemia is a frequently diagnosed condition during pregnancy linked to elevated risks of maternal and neonatal complications. Recent evidence indicated an association between maternal anemia and higher oxygen content in the umbilical artery and vein at delivery. For a study, researchers sought to explore the correlation between maternal anemia and electronic fetal monitoring (EFM) patterns indicative of fetal hypoxia. The primary objective was to investigate the relationship between maternal anemia and EFM patterns associated with fetal hypoxia, considering features like recurrent late and/or variable decelerations, minimal variability, tachycardia, or prolonged deceleration.

The secondary analysis drew from a prospective cohort study involving singleton term deliveries (2010–2014) with collected cord gases and complete blood count on admission. Maternal anemia was defined as hemoglobin ≤11.0 g/dL. The primary outcome assessed was a composite of high-risk category 2 EFM features in the last 60 minutes before delivery, while secondary outcomes included total deceleration area and total deceleration area >90th percentile. Adjustments were made for confounding factors through multivariable logistic regression.

Among 8,196 analyzed patients, 32.6% (2,672/8,196) were anemic, and 67.4% (5,524/8,196) were not. Anemic patients were less likely to exhibit high-risk category 2 EFM features (34.2% vs. 32.0%; adjusted risk ratio, 0.93; 95% CI, 0.86–0.99). Additionally, anemic women had reduced total deceleration area and a lower likelihood of total deceleration area >90th percentile (18.7% vs. 16.2%; adjusted risk ratio, 0.85; 95% CI, 0.77–0.94).

Maternal anemia was associated with a decreased likelihood of high-risk category 2 EFM features related to fetal hypoxia. It aligned with the observed correlation between maternal anemia and elevated umbilical cord oxygen content, suggesting a potential protective effect against intrapartum fetal hypoxia.

Source: ajog.org/article/S0002-9378(23)00249-1/fulltext