Fetal Abdominal Subcutaneous Tissue Thickness in Prediction of Fetal Weight in Term Pregnant Women: A Prospective Cohort Study

The fetal weight assessment by ultrasound is essential in obstetric practice to determine the labor mode, time, and management. It is an important to detect fetal growth abnormalities such as small for gestational age (SGA), fetal growth restriction (FGR) and large for gestational age (LGA) fetuses; thus, it could help in decreasing the perinatal morbidity and mortality rates [1]. Many methods have been introduced to estimate the weight in utero, and many studies have evaluated their effectiveness to detect the most accurate method [2]. Abnormal fetal growth can be diagnosed by ultrasound. Conventional ultrasonic measurements, such as estimated fetal weight (EFW) and abdominal circumference (AC) can distinguish LGA/macrosomia or LBW infants. Many studies have demonstrated that expected fetal weight (EFW) by the traditional techniques is not a reliable indicator of growth abnormalities; consequently several other sono graphic measurements have been proposed [3]. Ultrasound has its limitations despite the use of more than 50 different formulae to estimate fetal weight as their performance is poor at the extremes of fetal weight. There has been emerging interest in studying fetal soft tissue measurements to improve the detection of growth abnormalities [4].

Fetal Abdominal subcutaneous tissue thickness (FASTT) can be easily measured during the routine ultrasound examination of pregnant women. Numerous reports have shown FASTT measurement to be a good way of evaluating subcutaneous fat tissue [5].Furthermore, some researchers have investigated links between FASTT and diabetes [6].

However, to the best of our knowledge, no studies have investigated the association of FASTT with abnormal fetal growth in nondiabetic. For this reason, in this study we evaluated whether FASTT can predict birth weight or diagnose LGA and/or LBW infants in the third trimester.