Comparison of estimates of gestational age using last menstrual date; biparietal diameter; and ballard score

ABSTRACT

The gestational age of 30 Ghanaian neonates was estimated prenatally from ultrasound measurements of biparietal diameter (BPD); postnatally from the neonate's neurological and physical criteria using Ballard score. These two estimates were compared with the gestational age using the date of the last menstrual period (LMP) in mothers. The means (+/-SD) for the estimated gestational age were 38.96 +/- 2.77 weeks; 38.83 +/- 2.74; and 39.30 +/-2.03 for LMP;BPD; and Ballard score respectively. The difference between BPD and Ballard score was statistically significant (t=2.16;P0.05). While the three methods appear to be concordant among neonates 37 weeks and older; the estimates using Ballard score over-estimated the gestational age of neonates below 37 weeks