A new method for estimating the fetal weight is described, based on symphysis-fundus height and gestational age. The relationship between ultrasound-estimated fetal weight, gestational age, and symphysis-fundus height was determined using multiple regression analysis in a low-risk group. The accuracy of the regression formula was tested retrospectively on two target populations: a second low-risk group and a higher risk group undergoing elective delivery. The formula overestimated weight by 3.6%. The standard deviation of the random errors for the first group was 10.3% whereas in the second it was 11.9%. Fetal weight estimation using symphysis-fundus height and gestational age can be performed with an accuracy comparable to that of ultrasound.