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Am I Having a Boy or a Girl? | UItrasound & Sex Prediction

gender, pregnancy, boy, girl, female, male
Credit: xzoex | Shutterstock

You can find out ahead of time, or you can wait until birth. Often, relatives and friends pressure the soon-to-be parents to find out ahead of time for the ease of gift giving. Parents like to find out the sex of the baby to help decorate the nursery or plan accordingly with clothing. It also helps narrow down names when in the process of choosing the right moniker for the baby. Other people prefer the surprise, and the elation the moment that the doctor announces the baby's sex. There is also no definitive way to predict the baby's sex and be completely sure, so some parents prefer to remove the margin of error and wait until birth.

Either way, come up with a plan and figure out what works best for you.

What decides the sex of the baby?

The sex of the baby is decided long before you even know that you're pregnant. The egg cell contains a single X chromosome, while the sperm carries either an X or a Y. Depending on which sperm cell makes it to the egg, and whether it carries an X or a Y, is what dictates the sex of the baby. If the sperm is carrying an X chromosome, you've got yourself a girl. If the sperm carries a Y chromosome, you've got a boy. Essentially, the gender is determined at the moment of fertilization.

When and how can I find out the sex of the baby?

There are a number of tests that can reveal the sex of the baby, though they have some risk. Most commonly, ultrasounds can discover the sex of the baby between 18 and 20 weeks. An ultrasound exam uses high-frequency sound waves to scan a woman's abdomen and pelvic cavity. The scan creates a picture, called a sonogram, of the fetus and placenta. This is, however, not a completely accurate tool to discover gender. It depends entirely on the angle of the baby, the gestational age, and the technician's ability to read an ultrasound. It's also, for obvious reasons, much easier to confirm if the baby is a boy or not.

Chorionic villus sampling (CVS) can be done between eight and 11 weeks of gestation; it is usually only done for people who have a high risk of genetic abnormalities. This procedure involves removing a few chorionic villi cells from the placenta at the point where it attaches to the uterine wall. The most common method is transcervical — an ultrasound guides a catheter through the cervix to the placenta, where the cells are suctioned into the catheter.

Another method of CVS is transabdominal. The ultrasound guides a long, thin needle to the placenta and a sample of tissues is removed. It is similar to amniocentesis. In amniocentesis, the ultrasound guides a needle to a safe spot on the amniotic sac. A sample of amniotic fluid, which contains cells shed by the fetus, is collected and analyzed. Amniocentesis can be performed between nine and 18 weeks and is usually done in women 35 years or older, to check for genetic problems. It is not, however, completely accurate. These tests can determine the sex of the baby, though they carry a low risk of miscarriage. These should not be performed for the purposes of finding out the sex of the baby.

Old wives' tales

For centuries, people have been coming up with silly ways to figure out the sex of the baby. Here are a few gems that are completely medically inaccurate but entertaining. Either way, you have a 50-50 chance of finding out if you're having a boy or a girl.

  • In medieval times, "The Distaff Gospels" dispensed questionable and laughable medical advice that we now know to be false. According to the "Gospels," a woman who walks with her right foot first is having a boy, while the opposite means you're having a girl.
  • There's also the ring test — put a ring on a piece of string, and hold it over the bump. If the ring moves in circles, it's a girl, but if it swings from side to side, it's a boy.
  • There are some who believe that cravings can signify the sex of the baby. Craving sweets means giving birth to a girl, while salty and sour cravings are the sign of a boy.
  • Many believe that the shape of the bump and how the mother carries can tell the sex of the baby. A lower bump is a boy, while a higher bump is a girl. In reality, this is actually more about the muscle tone of the mother and baby.
  • One theory that might actually hold water is the morning sickness theory. Some people believe that severe morning sickness is the sign of a girl. This may actually have some root in fact, as the development of a baby girl can increase the level of estrogen in the body, which makes some women more nauseated.

There is no sure way to tell the sex of the baby. Though the ultrasound can be done at 18 to 20 weeks to make an educated guess, the only way to be 100 percent is to wait until the birth.

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