Role of Fetal Sacral Length in Assessment of Gestational Age by Ultrasound

Abstract

Background: Proper detection of gestational age is important for preventing premature labour. Foetal sacrum length can be used for detection of gestational age. Aim of the study: to develop a nomogram for foetal sacral length during pregnancy and assess its utility in detecting abnormal fetal growth. Patients and Methods: This cross-sectional research conducted at Alzahraa University Hospital's at obstetrics and gynecology clinic, from January 2020 to January 2021. Singleton uncomplicated pregnancies with no abnormalities. 300 pregnant women were investigated (240 average gestational age , 30 with small gestational age SGA and 30 with large gestational age LGA). From 16 to 40 weeks gestation . BPD, HC FL, AC, TCD and sacral length were examined. Results: There is no significant difference between the studied groups regarding demographic data. Fetal sacral length increases with gestational age and there is association between fetal sacral length “mm” and gestational age “wks. The relationship between gestational age and sacral length is described by a linear regression equation for fetuses with a gestational age of wks and show significant difference. There is significant difference between BPD, head circumference, and femur length with gestational age for the LGA and SCA foetuses. However TCD and sacral length show no significant difference between the expected and actual gestational age Conclusion: Foetal sacral length is simple and useful parameter can used as routine parameter, complementary tool in estimation of foetal growth and prediction of gestational age in normal and abnormal foetal growth.