Clinical estimation of fetal weight in labour by mothers and midwives

Summary

Recent studies suggest that pregnant women are accurate in estimating the weights of their unborn babies. Surprisingly, the accuracy of estimation by midwives has not been assessed considering that they conduct most normal deliveries. We recruited 386 women of mixed parity, at term, in labour and asked them, with their attending midwives, to estimate weight of the unborn baby. Estimations by women in their first full term pregnancy was similar to those of women with previous deliveries. Estimations to within 300 g of actual birth weight was 50 per cent in the nulliparous and 52 per cent in multiparous women, while at 500 g they were 70 per cent and 80 per cent respectively. Midwives were similar in their estimation of 65 per cent at 300 g and 85 per cent at 500 g of birthweight regardless of parity. This ability of estimating weight for all groups is however limited to the average-sized baby with the accuracy decreasing at extremes of birth-weight.