In a prospective descriptive study, the usefulness of symphysis-fundal height and the product of abdominal girth and fundal height in predicting birth weight 4000 g were examined. Fundal height and abdominal girth were measured at the time of admission on a sample of 795 parturient women at a teaching hospital in the Islamic Republic of Iran. Receiver operating characteristics curve analysis was used to select the best cut-off points. The product of abdominal girth × fundal height with the cut-off at 3900 g performed better for predicting birth weight > 4000 g, but for low birth weight, the regression model of fundal height with cut-off at 3000 g was a better predictor.