Fetal heart rate as a predictor of sex.

The purpose of this descriptive study was to determine the relationship between the fetal heart rate during the last trimester of pregnancy and the sex of the baby. The fetal heart rates of 51 subjects were auscultated and counted between 32 and 42 weeks of gestation with the use of ultrasound monitors. The mean heart rate for 23 males was 137.8 beats per minute (BPM) and for 28 females was 138.2 BPM. There was no significant difference found between the two groups. There was also no significant difference shown in individual fetal heart rates as the fetus matured from 34 to 38 weeks gestation. On the basis of these findings and a review of the literature, it was concluded that the fetal heart rate cannot be used as an accurate method for predicting the sex of the baby.