Correlation of fetal abdominal subcutaneous tissue thickness by ultrasound to predict birth weight

Introduction: Fetal growth abnormality is associated with changes in the soft tissue mass, which is decreased in growth restricted fetuses and increased in macrosomia. Objective: To correlate fetal abdominal subcutaneous tissue thickness (FASTT) measured by ultrasound at term and birth weight and to obtain a cut-off value of FASTT to predict large and small for gestational age babies in our population. Methods: FASTT was measured at the anterior 1/3^rd of abdominal circumference by ultrasound after 36 weeks and weight of the baby measured after birth. Results: There was positive correlation between FASTT and birth weight. FASTT of 6.25 mm was sensitive to predict large for gestational age (LGA) babies and had a high negative predictive value; FASTT measurement for prediction of small babies with birth weight < 2500 g was not sensitive. Conclusion: FASTT can be used as an additional indicator to predict large for gestational age babies along with other known birth weight indicators.