When Can You Find Out the Sex of Your Baby?

For some parents, finding out their baby's sex during pregnancy is an exciting milestone. And thanks to advances in technology, you can learn your baby's sex at several stages during pregnancy, ranging from as early as 10 weeks to as late as delivery day. Here's what expectant parents need to know about when can they find out the sex of their baby.

When and How You Can Find Out Your Baby's Sex

Historically, parents had to wait until their baby's birth to learn their sex. It's no surprise then that there is no shortage of old wives' tales about determining sex before birth. Inquiring minds want to know!

Today, however, there are multiple points during routine prenatal care when parents can learn the sex of their baby. In fact, it's so common to learn the sex of your baby before birth that parents who wish for the sex to remain a surprise often have to go to great lengths to avoid the information.

So, if you prefer to wait until delivery to learn your baby's sex, be sure to let your medical team know ahead of time, especially if you will have a lot of monitoring done during your pregnancy. (And they may need the occasional reminder, so don't be afraid to speak up!)

Parents who are just dying to know, on the other hand, are in luck.

Non-invasive prenatal testing (NIPT)

Non-invasive prenatal testing (NIPT) screens for genetic or chromosomal abnormalities in the fetus such as Down syndrome and offers the earliest chance to learn the sex of your baby. This testing usually happens after 10 weeks of pregnancy. The American College of Obstetrics and Gynecology (ACOG) now recommends NIPT for all pregnancies, regardless of risk or age.

NIPT analyzes blood drawn from the pregnant person, and it doesn't pose any risk to the fetus. The blood sample is analyzed for fragments of fetal DNA, called cell-free DNA (cfDNA) since it's outside of fetal cells. By analyzing the cfDNA, the NIPT screens for some chromosomal disorders, and it can see how many copies of the X and Y chromosome the fetus has, thus establishing the biological sex of the baby.

Chorionic villus sampling (CVS) or amniocentesis

Recommended in rare cases for some pregnant people, amniocentesis and chorionic villus sampling (CVS) screen for genetic abnormalities in a fetus, according to the Centers for Disease Control and Prevention (CDC). As a byproduct of performing the tests, parents-to-be can learn the sex of their baby based on chromosomes.

With amniocentesis, a needle is inserted through the abdomen into the uterus to sample amniotic fluid. The procedure carries a small risk of miscarriage, but it's generally very safe. The procedure is usually done between 15 and 20 weeks gestation.

On the other hand, CVS involves taking a sample of tissue from the placenta for screening, and it also looks at fetal chromosomes. CVS is usually done between 10 and 12 weeks of pregnancy, the CDC says.

Ultrasound

Parents-to-be can also learn their baby's sex during routine ultrasounds—but keep in mind that determining the baby's sex is not the primary goal of an ultrasound. Ultrasounds from your doctor are ordered for medical reasons and finding out the sex is usually a "bonus."

For example, the anatomy scan, which usually takes place between 18 and 22 weeks, confirms the proper growth of the fetus. The technician takes a variety of measurements (including crown-to-rump length), estimates fetal weight, examines the placenta, and checks internal organs and sex organs, according to Johns Hopkins Medicine.

Pregnant people can get a fairly accurate estimate of the baby's sex as part of the anatomy scan if they wish. Often an ultrasound technician or doctor will ask if the patient would like to learn the sex of the baby, and they may decline if they prefer to be surprised.

Unlike NIPT, CVS, and amniocentesis, which use fetal chromosomes to identify the sex, ultrasound relies on the visual presentation of the fetus's developing genitalia, which can be misleading, particularly if they're in a position that hides their genitalia. In this case, a second ultrasound might be scheduled for the sex reveal.

Genetic screening with IVF

If a couple conceives with in vitro fertilization (IVF)—a fertility treatment that involves combining the egg and sperm in a petri dish, then inserting the resulting embryo directly into the uterus—the baby's sex might be known from the outset.

You can thank preimplantation genetic screening, in which the full chromosomes of an embryo are evaluated, usually to choose the healthiest embryo for the IVF procedure. At that point, prospective parents can sometimes choose the sex of the embryo they want to implant. This is often referred to as "gender selection," and not every clinic offers it.

The Limits of Finding Out a Baby's Sex

While parents-to-be have several opportunities to learn their baby's sex during pregnancy, it's worth remembering the limits of this information. Babies grow up to be kids who can tell their parents about themselves, and the labels they're assigned at birth don't always match their feelings about themselves.

Gender identity, according to the Human Rights Campaign, refers to a person's internal sense of identity, which is distinct from anatomy. Some kids are non-binary and others are transgender, meaning their gender identity doesn't match the sex they were assigned at birth. Some states now allow parents to change the gender on their child's birth certificate to "X," which allows the kid to officially claim a gender identity when they're ready.

And even if the baby is cis-gender (meaning their assigned sex and gender identity are the same), this can't tell you anything about their personality, hopes, or talents. Heck, it can't even tell you if your child will prefer the color blue or pink. Like all things with our children, their own individual characteristics will reveal themselves over time, with love and care from you.