While gender cannot be accurately determined by genetics, there are several tests to determine sex before birth — including some at-home options.
In a world where pretty much everything we want can be same-day delivered to us — movies and music, our favorite restaurant foods, prescription medications, and even toilet paper — having to wait until your 20-week ultrasound to find out your baby’s sex feels downright prehistoric.
Well, you’re in luck: Some pretty big strides have been made in the last few years involving the timing and ease with which you can find out your baby’s sex.
We’re not quite at the “submit your order online and receive it within 30 minutes” point. But developments in noninvasive prenatal tests (NIPTs) mean you can be let in on this little secret with a simple blood test — even if sex determination isn’t their main purpose — as early as 10 weeks into your pregnancy.
Interested? Here’s what you need to know.
Language matters
It’s important to note that your baby’s sex and their gender are not the same thing. Recent data from the CDC indicates that at least 1.4% of young people in the U.S. identify as transgender. Due to increased social support and reduced bigotry, this percentage has grown in recent years.
Learn more about the difference between sex and gender here.
In the past, the standard of care for those at risk for having a baby with certain genetic conditions or other complications was one of two genetic screenings performed in the first trimester: chorionic villus sampling (CVS) or an amniocentesis.
These provide a pretty accurate picture of your baby’s genetic health, but they’re also invasive and carry a risk of miscarriage.
So, not ideal or worth the risk without other medical reasons… though they do also allow you to find out your baby’s sex before the 20-week ultrasound.
Now expectant parents have another option.
About 10 years ago, researchers developed a much less invasive test called cell-free DNA screening. Because your baby’s DNA actually shows up in your blood, it can be used to screen for things like:
- Down syndrome
- Edwards syndrome
- Patau syndrome
These are three of the most common genetic fetal conditions.
Cell-free DNA screenings, which reveal the likelihood of your baby having one of these genetic conditions, used to be recommended only to those with high-risk pregnancies. But now they’re now being offered more widely.
How does this type of screening work?
Basically, you go to your doctor’s office or local lab and give a sample of your blood. In theory, any genetic abnormalities related to those three chromosomal defects will appear in your baby’s DNA — and, therefore, in your sample.
You only need to be 9 or 10 weeks pregnant, depending on the specific test used. Several companies provide these NIPTs to practitioners.
Some offer slightly more advanced screening, and some differentiate between abnormalities found in baby’s DNA versus your DNA while others don’t. Your doctor can tell you which NIPT is available to you.
Despite what you might think based on how easy-peasy this all is, most NIPTs are actually quite accurate.
You’ll receive results only for a limited number of abnormalities — making it a not-great choice for people with concerns about other rarer conditions.
But the accuracy for these tests is about 90 percent for Down and Edward syndrome, per a
The only caveat? You can’t take one of these blood tests just to find out your baby’s sex. Although people casually call them “gender blood tests”, that’s not their primary purpose.
They identify your baby’s sex because some genetic conditions are sex-based. But they’re genetic screening tools first and foremost.
If you do just want an early read on (or, perhaps more accurately, prediction of) your baby’s sex and not a full genetic workup, you might be better off using an at-home sex DNA kit.
These tests work basically the same way as the lab tests do, but they don’t screen your blood for any genetic abnormalities in your baby’s DNA. Instead, they look only for male chromosomes.
For those who aren’t science whizzes, this means that if a Y chromosome is detected, you’ll be told you’re having a boy; if not, a girl. Basic biology for the win!
Currently, only a couple of companies have these sex DNA kits. They all offer a similar service: They mail you a kit with instructions on how to collect a small blood sample and send it back to their lab for analysis.
It’s recommended that you be at least 7 to 8 weeks pregnant for these tests.
Here’s a breakdown of the three major companies offering this service:
- SneakPeek. The standard package, with results in 5 to 7 days, costs $79. For results in 72 hours, you’ll have to pay $149. Accuracy is said to be 99.9 percent at 8 weeks pregnant.
- Peekaboo. For $65, you can receive and send back this kit, expecting results in 72 hours after they receive your sample. They state their accuracy rate is 99.5 percent.
- eGenderTest. If you’re at least 9 weeks pregnant, you can take this test for $169. The accuracy rate is alleged to be 98 percent; results take 3 business days to turn around once they receive your sample.
For the most part, these companies claim their tests are just as effective in correctly identifying sex as the NIPT tests performed at a doctor’s office.
However, there aren’t any independently published studies confirming this claim.
Plus, there’s more room for error here than with a laboratory test: The sample could be contaminated at your house or during the mailing process, and you can’t know for sure what the lab conditions are at each individual company offering the service.
For example, in theory, if your husband, son, or other male relative handles your sample, the test could pick up a Y chromosome even if you’re pregnant with a girl.
Assuming you didn’t do any kind of sex selection via in vitro fertilization (IVF) — and you’re not relying on old wives’ tales, which we don’t recommend! — there’s really only one non-blood test to know your baby’s sex: an abdominal ultrasound.
Somewhere around 14 weeks’ gestation, your baby’s genitals are developed enough to be spotted on an ultrasound.
But unless you have another reason (like a potential complication) for having an ultrasound at this point in your pregnancy, you’ll have to wait until your anatomy scan is scheduled. This usually happens around the 20th week of pregnancy.
It’s probably better this way, anyway. In the first trimester, the accuracy of sex predictions with ultrasound is only about 75 percent, according to a
And still, even though you’re getting a made-for-TV movie of your baby’s actual body growing inside your belly during the anatomy scan, the sex results of a second trimester ultrasound should always be taken with a grain of salt
Sometimes babies don’t cooperate with the timing of your appointment, and sometimes the ultrasounds are just plain misinterpreted.
NIPTs are a safe way to detect chromosomal abnormalities earlier in pregnancy than more invasive kinds of genetic screenings. They’re generally very accurate (though not 100 percent).
As a nice bonus, they can tell you whether you’re having a boy or a girl.
There are tests you can try yourself at home as well. But personally, we recommend going through your doctor so you can be sure your sample is processed professionally.
You’ll be able to access genetic counseling services, too, that way.
That said, if you just can’t wait to find out your baby’s sex and don’t need their genetic info yet, you can opt to take an at-home DNA test for fun.
