Comparison of correlation of various methods of gestational age assessment in term neonates

Knowledge of gestational age of newborn babies may modify the details of their care. Though gestational age is usually calculated from the date of mother’s last menstrual period this date is not known with certainty in large majority of pregnancy. In others there may be misleading information especially when the menstrual cycle is irregular, when conception is shortly after a previous pregnancy or when the mother was taking oral contraceptives shortly before conception. Hence the need of multiple modalities to confirm the gestational age and the reliability of modalities is a major concern. Our study is undertaken to compare the correlation of gestation age assessment by three methods viz., gestational age assessment by last menstrual period dates, gestational age assessment by last trimester ultrasound and gestational assessment by post-natal assessment of modified Ballard score. This study is a prospective study conducted in a rural medical college hospital. Total of 150 term babies were enrolled in the study. Duration of the study was two years. The gestational age of the neonates was calculated by all 3 methods and the correlation was assessed. The study concluded that the modified Ballard score overestimates the gestational age and the third trimester ultrasound underestimates the gestational age.