Study of Ultrasonographic Changes of the Adrenal Gland in Growth Restricted Fetus

Background: Fetuses with Fetal Growth Restriction (FGR) are at increased risk of chronic intra-uterine hypoxia, due to increased secretion of corticosterone from the fetal adrenal glands. This plays a major role in the cardiovascular and circulatory adaptation of FGR fetuses. These modifications are untimely identified by sonographic imaging. Objective: To study the association between ultrasound features of the adrenal gland and growth restriction in the fetus. Methods: A total of 104 pregnant women (52 FGR pregnancies and 52 controls) were evaluated between 28 and 36 weeks of gestation. All the study participants underwent transabdominal ultrasonography to measure bilateral fetal adrenal gland volume and fetal zone volume, corrected for gestational age. They were followed up until delivery. The two groups were compared to analyze the perinatal outcome in relation to ultrasonographic changes in the adrenal gland. Results: The adrenal gland measurements were significantly larger in fetuses with FGR as compared to the control group. FGR group had a larger corrected adrenal gland volume(cAGV) and fetal zone and adrenal gland (FZ/AG) ratio A statistically significant correlation was found between the two groups regarding gestational age at delivery, birth weight, APGAR score, and NICU admissions. Perinatal morbidity was found to be higher among women diagnosed with FGR, i.e., 14 (53.84%). Conclusion: Fetal adrenal gland size measurement is important to identify FGR fetuses that are vulnerable to hypoxia. It helps the obstetrician prepare for effective in-utero management to reduce perinatal morbidity and mortality.