With a lot of old traditional beliefs and misconceptions on how the heart rate can predict the gender of the fetus, most pregnant mother’s often get carried away. The prediction can be as early as the first trimester when a fetal heart rate below 140bpm means; it is a girl. Otherwise, it is a boy.
The truth is the baby’s heart begins to beat only by week 6 of pregnancy, and small flickering light of the heart beating can be seen in the ultrasound. The heart rate slowly increases from 90 to 110bpm until week 9 of pregnancy to stabilize at 140 to 170bpm.
And for questions like 144- 148bpm baby heart rate boy or girl? This article debunks the myth.
Fetal heart rate and gender- What does the research say?
One of the old wives’ methods to reveal the baby’s gender is to inspect the ‘baby bump’- the woman with a low baby bump has a boy, and one with a high baby bump is likely to have a girl. Even before ultrasonography, these myths and beliefs with no unscientific reasoning circulated among many traditional societies.
To understand the correlation between heart rate and gender prediction, a study was conducted by D.S. McKenna et al., Dept of Obstetrics and Gynecology, Wright State University, Ohio. In the Fetal Diagnosis and Therapy study, researchers examined 966 first trimester sonography of women under 14 weeks of gestation. A similar sonographic examination was conducted in the second trimester between 18 to 24 weeks among the same pregnant women.
By then, only 477 women could meet their study criteria. Of these pregnancies, 244 were revealed to be girls, while 233 were boys. The fetal heart rate (FHR) showed no significant difference between the girl and the boy child. The average FHR for girls was 151.7 + 22.7bpm, and for boys, the average FHR recorded was 154.9+22.8bpm.
Contrary to the beliefs, the fetal heart rate of male and female babies showed no significant difference. Thus, proving that the heart rates of 148 or 144 bpm during the first trimester does not indicate the baby’s gender- boy or girl.
McKenna D.S. · Ventolini G. · Neiger R. · Downing C., Gender-Related Differences in Fetal Heart Rate during First Trimester, https://doi.org/10.1159/000089065.