Comparison of Middle Cerebral Artery Doppler and Cord Blood Hemoglobin in the Diagnosis of Fetal Anemia among Rh-negative Pregnant Women

Abstract

Background: Most prevalent cause of fetal anemia is Rh incompatibility between the mother's and the fetus's blood types, where antibodies from the mother damage the fetus's red blood cells causing fetal hemolytic anemia.

Objective: To compare the Doppler of the middle cerebral artery of the fetus and cord blood hemoglobin to diagnose fetal anemia among Rh-negative women in the last trimester of pregnancy.

Methodology: This was a cross-sectional study conducted at the Gynecology & Obstetrics Department, Mercy Teaching Hospital Peshawar, from February 2020 to May 2021. A total of 126 Rh-negative blood group women were included who were in the last trimester of the pregnancy. Ethical approval was obtained from Ethics Committee and informed written consent was taken from the study participants. Middle cerebral artery Doppler peak systolic velocity was checked at 28^th, 32^nd, and 34^th week of gestation. If middle cerebral artery Doppler peak systolic velocity changes were present, then patients were closely monitored and managed appropriately for post-delivery assessment of cord blood fetal anemia. A pre-designed structured proforma was used to collect patient details.

Results: Mean age of 126 pregnant mothers was 28±7 years, and the mean parity was 4.57±2. The overall frequency of fetal anemia among Rh-negative women predicted by middle cerebral artery Doppler peak systolic velocity was 59 (46.8%), while anemia on cord blood sampling after delivery was found in 43 (34.1%) of babies. No anemia was found in  83 (65.8%) study participants. The sensitivity and specificity of middle cerebral artery Doppler were 100% and 84% respectively.

Conclusion: Middle cerebral artery Doppler can be a simple noninvasive method to detect fetal anemia before the development of hydrops fetalis with high sensitivity and specificity.