The truth about fetal heart rate and ways to find out the sex of your baby
Practically every pregnant woman has heard some old wives’ tales about the sex of her baby. “You’re carrying low, so it must be a boy.” “You don’t have morning sickness? It must be a girl.”
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
While these myths can be fun to toss around, there’s no science to back them up. And the same goes for the belief that baby’s heart rate predicts gender. Obstetrician Justin Lappen, MD, explains the facts about fetal heart rate and why it doesn’t reveal the sex of your baby.
When someone talks about their baby’s gender, they’re really referring to the baby’s sex. “Sex” refers to traits that make a person biologically male or female.
“Gender” refers to a person’s role in society or the gender a person identifies with. The popular term “gender reveal” is often (mistakenly) used when referring to finding out the baby’s sex.
You can often see and hear your baby’s heartbeat at your regular prenatal appointments. Using ultrasound, your obstetrician can measure the heart rate of your fetus as early as six to eight weeks into pregnancy.
An average fetal heart rate ranges from 110 to 160 beats per minute (bpm) and changes when the baby is active. Some babies have heart rates that are slower or faster than average. But this has nothing to do with the sex of your baby.
“The fetal heart rate does not predict the sex of the baby,” says Dr. Lappen. “Studies have found no difference between male and female fetal heart rates.”
While the baby’s heartbeat may not clue you in on boy vs. girl, you can find out with these tests:
You can usually find out the big news during the second trimester ultrasound. It takes place around the 20th week of pregnancy and checks your baby’s growth and well-being.
“During this ultrasound, we are usually able to identify male and female genitalia,” says Dr. Lappen. “But before 16 weeks or so, an ultrasound isn’t a reliable way to determine the sex of the fetus.”
A prenatal cell-free DNA screening uses a sample of the mother’s blood to look for DNA from the pregnancy. The results of this screening can reveal whether a baby has a higher risk of certain chromosomal disorders.
The results also show whether you’re having a boy or a girl. But doctors typically don’t use this test exclusively as an early gender reveal.
“Cell-free DNA tests are usually for women with a higher risk of having a baby with a chromosomal abnormality,” explains Dr. Lappen. “If a woman is interested in a cell-free DNA screening, she should talk with her obstetrician.”
Prenatal genetic tests help doctors diagnose certain genetic disorders in a fetus. And these tests also reveal the baby’s sex. Prenatal genetic tests include:
These tests carry a small risk of miscarriage or infection, so they shouldn’t be your go-to for finding out your baby’s sex.
“Anyone can have an amniocentesis or CVS if they choose,” says Dr. Lappen. “But they’re not something we would use just to find out the baby’s sex. These tests are helpful for women who want to know if there are any problems with their pregnancy.”
There is no “perfect time” to find out your baby’s sex. Some women find out early during a prenatal screening or test. Many get the news during their 20-week ultrasound. And others choose to wait until delivery day.
“There are safe and accurate ways to find out the sex of your baby,” Dr. Lappen says. “Talk to your obstetrician or midwife so you can make the decision that works best for you.”
Learn more about our editorial process.
Staying up-to-date on vaccines encourages a healthy pregnancy, but not all vaccines are recommended when you’re pregnant
Science says only one way actually works, but there are a few others that are still safe to try
When a growing fetus puts pressure on your abdomen, your belly button may pop out or even flatten
Talk with them about their new sibling early and often
Dental care is not only safe during pregnancy, but it’s also highly recommended
A healthy pregnancy diet includes good amounts of folic acid, DHA, calcium and more
If left untreated, you risk complications, early labor and passing the infection to your baby
Lifestyle changes, like a healthy diet and exercise, can help with fertility issues
Your metabolism may torch 1,300 to 2,000 calories daily with no activity
A gentle touch in all the right places may help drain your sinuses
