Prediction of gestational age of newborn by measurement of foot length at birth

Abstract

Background: Gestational age of the newborn can be assessed by various methods. Aim of this study was to estimate the gestational age using foot length of the neonate and to find the correlation between foot length and gestational age assessed by last menstrual period and first trimester ultrasound.Methods: It was a hospital based prospective cross-sectional study done at Newborn ward, Department of Pediatrics, MGM Govt. hospital attached to KAP Viswanatham Govt. Medical College, Tiruchirappalli, involving 170 newborns with 10 babies in each gestational age ranging from 26 weeks to 42 weeks. Gestational age of all babies were assessed using last menstrual period, first trimester ultrasound and New Ballard Score soon after birth. Right foot length of each baby was measured from heel to tip of great toe or second toe whichever was longer, within 12-24 hours of life. Measurements were taken using a plastic ruler, measuring tape and by measuring the length of foot print ink impression. Gestational age obtained by various methods were assessed for their correlation with foot length.Results: Positive correlation was obtained between foot length and gestational age determined by LMP (r= 0.965) and ultrasound (r= 0.964). Hence foot length could be reliably used to predict gestational age of newborn.Conclusions: Foot length measurements can be used as a non-invasive alternative method to assess gestational age of newborn, especially by community health workers and thus can facilitate the early identification of preterm babies.