Fetal vascular adaptation before and after treatment of severe maternal anemia in pregnancy

Abstract

Objectives: To use color Doppler ultrasonography indices to study the effects on fetal circulation of treating severe maternal anemia.

Methods: A prospective cohort study enrolled patients who were at 30-34weeks of pregnancy and had hemoglobin levels below 70g/L between November 1, 2011 and March 31, 2013 at a hospital in New Delhi, India. A control group consisting of patients with the same duration of pregnancy and with hemoglobin levels above 110g/L was included. Umbilical artery and middle cerebral artery velocimetry were performed using color Doppler ultrasonography at admission and after 4weeks and 6weeks of treatment.

Results: The maternal anemia cohort demonstrated a significantly lower middle cerebral artery resistance index and middle cerebral/umbilical artery resistance ratio (P<0.001) at admission. Following 4weeks of treatment for maternal anemia, significant increases in these parameters were observed (P<0.001).

Conclusion: Fetuses of individuals with severe maternal anemia demonstrated altered cerebral and umbilical artery flows. Normal flows were restored following treatment of maternal anemia.

Keywords: Cerebral/umbilical resistance ratio; Doppler velocimetry; Maternal anemia; Middle cerebral artery; Peak systolic velocity; Pulsatility index; Resistance index; Systolic/diastolic ratio; Umbilical artery.