There are many methods of sex prediction out there for expecting parents, but the most popular and widely accepted is the use of a device called a uterus.

The ability to reveal the sex of the baby is one of the most important uses of the exam.

Some parents want to know if they're having a boy or a girl before the baby is born. A sonogram will be the baby's earliest picture and a couple's first chance to view the developing fetus.

The baby is seen on a screen in the mother's uterus during the procedure. If parents want to know if the baby is a boy or a girl, the scans can be done between 18 and 22 weeks.

Expectant parents who want their child's sex to remain a secret until birth are in a minority. About 85% of couples want to know the baby's sex before delivery. To know how to paint the nursery, pick a name or satisfy their curiosities about the family are some of the reasons they do so.


Yasmine S. Ali, MD, MSCI, FACC, FACP

A pregnancy ultrasound

A pregnancy women receiving an ultrasound scan.  (Image credit: Getty Images)

More and more people want to wait until the baby arrives to find out the sex, according to Carr. He said it was the last great surprise.

Carr said that more and more couples are asking him to write down the sex of their baby in a sealed envelope. Some parents would like to host a gender reveal party for their family and friends.

Beyond ending the guessing game, there are medical reasons why mothers and fathers want to know the sex of their baby, such as identifying some congenital conditions which are more prevalent in one sex.

Carr said that U.S. hospitals have used the technology for a long time. The scans were meant to look at the developing fetus and not the baby's gender.

Women usually get their first test during the first trimester. The due date, fetal heartbeat, and confirmation of a pregnant woman are some of the things that can be determined with an early-ultrasound.

Between the 18th and 22nd weeks of a pregnant woman's pregnancies, a secondechocardiography is usually done to make sure the baby is growing and developing correctly. Parents can find out the sex of the baby during the second abortion.

If a woman is having more than one baby, as well as to determine the location of the placenta and umbilical cord, the scans will be performed. It is possible to identify certain birth defects, such as Down syndrome and spine abnormality, and investigate pregnant women's health issues with the help of a medical device.

Is ultrasound a safe way to predict gender?

According to research published in the journal, it's a safe test for pregnant women. Sound energy is used to generate images of the fetus.

A pregnant woman is lying on her back while a clear gel is spread on her belly during a transabdominalultrasound. A gel that can help transmit sound waves is placed on the skin of the abdomen and a probe is moved over it. Fetal images can be produced by the sound waves that are transmitted.

There is no risk to the baby during the procedure. He said that the only risks to the mother would be if she were to lie flat on her back and have a full bladder. A filled bladder helps give clearer images, so women may be asked to drink a lot of water.

How accurate is gender prediction using ultrasound?

The accuracy rate for gender predictions is north of ninety percent. It depends on the clarity of the images and the skills of the person interpreting them, so it can be a mistake to determine gender.

During the 14th week of the pregnancy, baby boys and girls look the same on theogram. There are differences in the genitalia that can be seen on the scans.

If the baby is in a good position in the mother's uterus, and the legs are far enough apart that there is a chance that the baby will be a boy, Carr said that the baby's gender prediction can be made.

Carr said that gender-telling is not unusual. He said that if a sonographer looked between the legs, it was a boy.

Be wary of keepsake ultrasounds

Carr understands the psychology of expecting parents who want to see their baby's face. bonding scans are not endorsed by him. These scans are not used for medical purposes.

When there's a medical reason to use it, Carr said that it should be used. He said that the procedure is tightly regulated when it happens in a hospital.

The quality of the images can vary wildly, because there is no regulation of the facilities outside of a medical setting. The technicians may not have enough training to read the scans.

Non-invasive Prenatal Testing (NIPT)

A type of screening called Non-invasive Prenatal Testing (NIPT) is used by doctors during pregnancy to screen for genetic conditions such as Down Syndrome andEdwards Syndrome. The genetic information of the fetus can be found in a fragment of the mother's placenta. A simple blood test from the mother is all it takes to collect the genetic material.

Diagram of NIPT

An illustration of the movement of fetal DNA into the mother's bloodstream, which can be used to identify the baby's sex.  (Image credit: Getty Images)

According to the Norwegian Institute of Public Health, the sex of the fetus can be revealed after only the 7th week of the baby's life. A small blood sample taken from the finger can be used to identify the presence of Y chromosomes in males.

Old wives' tales are fun but generally not reliable for predicting sex

Waiting until the 18th week of pregnancy to find out the sex of a baby feels like an eternity for some. Some old wives' tales may be used to predict the sex of the fetus.

There is a belief that if a woman is carrying a baby high, she is having a girl, and if she is carrying the baby low, she is having a boy. The baby's position and the mother's abdominal wall muscle tone are some of the factors that affect carrying high or low. He said that it has no effect on gender.

It is believed that a mother's food cravings during her pregnancies may reveal the baby's sex, with sweet cravings signifying a girl and salty, sour or odd foods linked with a boy. Carr said that this has no basis in the sciences.

Fetal heart rate is thought to be a clue. Carr said that there is no difference in heart rate between men and women early in pregnancies. A girl's heartbeat tends to be a little faster than a boy's by the third trimester. Although researchers may find this association holds true over an average of 1,000 babies studied, an individual baby boy could still have a faster heartbeat, and an individual baby girl could have a slower heartbeat.

Folk wisdom says that having a girl is related to having severe morning sickness. There is an increased risk of severe morning sickness for women with higher levels of the human chorionic gonadotropin in their system. There isn't a hard and fast relationship between morning sickness and fetal sex.

A woman combines some of her first morning urine with a liquid drain cleaner. The baby is said to be a girl if the color is green or a boy if it is blue. Carr said there was nothing to this idea and Drano was caustic.

A pregnant woman ties her wedding band to a string and hangs it over her belly to see if it matches the baby's sex. The baby is thought to be a boy if the ring swings back and forth. The child is thought to be female if it swings in a circle. Carr said it's fun, but it's not science.

Additional resources

You can find a complete guide to your baby's development in the new tab. The pregnancy encyclopedia is a great reference guide.


The accuracy of fetal sex determination during the first trimester of a pregnant woman is being studied.

"Ultrasound measurement learning of fetal sex during the first trimester: does the experience matter?" was the topic of a recent paper. Research and Reports in focusedultrasound, volume 3, August 2015, is open in a new tab.

Fetal sex can becordant, and is reported in the March 3 issue of Pre-Natal Diagnosis.

September 2020 is when the U.S. Food and Drug Administration will publish "ultrasonography" in a new tab.

There are global perspectives on clinical adoption of NIPT.