When can you find out your baby’s gender? Every way, week by week

Every way to find out, week by week

Weeks count from the first day of your last period. Each test or scan detects the baby’s sex, from chromosomes or anatomy. In week order, with sources below:

1. From 6 weeks, makers say: an at-home blood test. You mail a blood sample to a company’s lab, and the timing and accuracy figures are the company’s own.
2. From about 10 weeks: cell-free DNA screening (NIPT). A blood test your doctor or midwife orders to screen for chromosomal conditions. It can report the sex too.
3. From 10 to 20 weeks: CVS or amniocentesis. Gene tests offered only for medical reasons, with a small risk of miscarriage. They can show the sex too.
4. 11 to 14 weeks: an early medical scan. Some people try to read the “nub,” but calls this early are less sure.
5. From about 13 weeks: an elective gender scan. You book it yourself at a keepsake studio. It isn’t medical care.
6. About 18 to 22 weeks: the anatomy scan. A medical scan of your baby’s development. In most cases it can show the sex, if you ask and the hospital’s policy allows.
7. At birth. You see for yourself.

Blood tests: the earliest answers

At-home blood tests: from 6 weeks, makers say

You collect a small blood sample at home and mail it to the company’s lab. UPMC, a Pittsburgh health system, describes “a small blood sample from a finger prick” (UPMC). SneakPeek, sold by Myriad Genetics, uses a device pressed on the upper arm (Myriad Genetics). SneakPeek says you can test “as early as 6 weeks into pregnancy” (SneakPeek).

• How sure. The company says its test has “clinically-proven over 99% accuracy” (website, October 2026). Two independent reviews looked at research lab tests, not home kits. A 2011 review in JAMA pooled 57 studies, published from 1997 to 2011, that tested mothers’ blood or urine for a boy’s Y-chromosome DNA in 6,541 pregnancies. Blood tests performed well, but tests on urine, and tests before 7 weeks, were unreliable. Before 7 weeks, they picked up a boy in 74.5% of pregnancies with a boy (Devaney and colleagues). A 2012 review of 90 blood-test studies, covering 9,965 pregnancies, found little change by week (Wright and colleagues). UPMC calls home kits “expensive and less accurate” than tests your provider orders.
• Cost. In October 2026, SneakPeek listed its at-home test from $99, on sale for $74, including shipping and lab processing.
• What it can’t do. “SneakPeek cannot confirm pregnancy,” the company says, and its tests are “for informational and educational use only.” Its FAQ warns that “male helpers have been found to contaminate the DNA samples, causing incorrect results” (SneakPeek FAQ).

Cell-free DNA screening (NIPT), from about 10 weeks

Your doctor or midwife orders this blood test. It screens for chromosomal conditions such as Down syndrome (MedlinePlus), and the sex is a side result. Cleveland Clinic explains: “Because NIPT screens for sex chromosome conditions, it can also tell whether XX or XY chromosomes are present.” It “can be done as early as 10 weeks of pregnancy,” and results can sometimes take up to two weeks (Cleveland Clinic).

• Who gets it. In the U.S., “Healthcare providers offer NIPT to all pregnant women,” Cleveland Clinic says, and having it is up to you. In England, the NHS offers it after a higher-chance result from earlier screening, and its version “does not screen for other conditions or fetal sex” (NHS England).
• How sure. Cleveland Clinic calls the sex result “highly accurate, but not 100% accurate.” With twins, UPMC says, it’s only accurate if it finds no Y chromosome (all girls) or the twins are known to be identical.
• What it can’t do. It’s “a screening only,” not a diagnosis. A result suggesting a condition needs a diagnostic test, such as CVS or amniocentesis, to confirm it (MedlinePlus, Cleveland Clinic).
• Cost. It depends on your insurance and the lab. In 2025, NPR reported that Natera, a testing company, offered one patient its $349 cash price before billing her insurer $4,480 (NPR).

If a blood test and a scan disagree, or two results clash, tell your doctor or midwife. There are several possible explanations, a few of them medical, and only they can look into it (Dhamankar and colleagues, 2020). A genetic counselor can also explain your options, Cleveland Clinic notes. Can an ultrasound be wrong about the gender? covers what to do next.

CVS and amniocentesis: for medical reasons only

Both test the baby’s genes. CVS (chorionic villus sampling) “takes a small sample of cells called chorionic villi from the placenta” (Cleveland Clinic), and amniocentesis takes a little of the fluid around the baby. “When looking at your baby’s genes, they can also tell their sex,” UPMC says, even for each twin (UPMC). Cleveland Clinic calls each test about 99% accurate for the conditions it looks for (Cleveland Clinic).

• When. CVS at 10 to 13 weeks, Cleveland Clinic says, or usually 11 to 14 in England (NHS). Amniocentesis usually at 15 to 20 weeks (Cleveland Clinic).
• Who. Your doctor or midwife offers them for a medical reason, such as a higher-chance screening result or a family history of a genetic condition. “CVS testing isn’t a standard part of your prenatal care,” Cleveland Clinic says. Of amniocentesis, UPMC says: “This test is only done when necessary.”
• The risk. Each carries a small chance of miscarriage. After CVS, the NHS says, it’s “thought to be less than 1 in 200 for most pregnancies.” After second-trimester amniocentesis, Mayo Clinic puts it at about 0.1% to 0.3% “when done by a skilled person using ultrasound” (Mayo Clinic).

So neither is a way to find out the sex on its own, though the results can include it.

Ultrasound, from the “nub” to the anatomy scan

11 to 14 weeks: early scans and the “nub”

Hospitals in England offer a scan at 11 to 14 weeks. But “Finding out the sex of your baby is not offered as part of the national screening programme,” the NHS says (NHS). One early method judges the angle of the genital tubercle, nicknamed the “nub,” from the side. In a 1999 study by London researchers of 172 pregnancies scanned before CVS, a nub angled more than 30 degrees from the line of the lower back was read as a boy (Efrat and colleagues).

Calls this early are less sure. At a specialist private obstetric practice in New South Wales, Australia, 7 sonographers predicted the sex at routine scans of 640 babies across all three trimesters. They used a side view in the first trimester. At 11 to 14 weeks, they were right for 75% of babies, counting those they couldn’t call; under 12 weeks, the “overall success rate” was 54%. The abstract gives no group sizes. The authors concluded that “predictions prior to 12 weeks should be discouraged” (Kearin and colleagues, 2014). How accurate is a gender ultrasound at 13, 14, 15 and 16 weeks? has the study numbers for each week.

From about 13 weeks: an elective gender scan

You book an elective (keepsake) scan yourself, with no referral, to see your baby and find out. Studios set their own first week, and some book from 13. It isn’t medical care: it doesn’t check your baby’s health or anatomy, or replace any scan your doctor or midwife orders.

• How sure. In the Australian practice’s routine medical scans, every prediction made after 14 weeks, into the third trimester, was right; the abstract doesn’t say how many babies that was, or how many got no call. Results varied with sonographer experience, the week and the baby’s sex, the authors wrote. The NHS adds that “it’s not possible for the sonographer to be 100% certain about your baby’s sex,” for example when a baby lies in an awkward position (NHS). What “90% sure it’s a girl” means explains a sonographer’s confidence.
• Safety. The FDA and the American Institute of Ultrasound in Medicine (AIUM) discourage scans done only for keepsakes (FDA). The AIUM says using ultrasound without a medical reason to see the baby, take pictures or identify the genitals “is inappropriate and contrary to responsible medical practice” (AIUM). ACOG says ultrasound should be used only to answer a medical question or bring a medical benefit (ACOG Committee Opinion 723). Safety, in plain words has their statements, and Is an early ultrasound safe for the baby? weighs the evidence.
• Where it’s allowed. Not everywhere. Connecticut allows obstetric ultrasound only for a medical or diagnostic purpose, ordered by a licensed provider (AuntMinnie). Germany has banned non-medical ultrasound in pregnancy since January 1, 2021 (Deutsches Ärzteblatt).

About 18 to 22 weeks: the anatomy scan

This medical scan, ordered by your doctor or midwife, checks how your baby is developing. In the U.S., it “happens around 18 to 22 weeks of pregnancy.” “In most cases, you can also learn the sex,” Cleveland Clinic says, depending on your baby’s position (Cleveland Clinic). The U.S. practice guideline lists the external genitalia only if medically indicated or if the patient wants to know (ACR–ACOG–AIUM–SMFM–SRU), so say at the start whether you do.

In England, it’s usually at 18 to 21 weeks (NHS). Finding out “depends on the policy of your hospital,” the NHS says, and “Some hospitals have a policy of not telling patients the sex of their baby” (NHS). India goes further: its law bans determining or disclosing a baby’s sex before birth (PC&PNDT Act, 1994).

In the U.S., it’s part of your prenatal care, so check your plan. Without insurance, GoodRx’s 2024 estimated national averages were $459 for a “routine fetal ultrasound” and $954 for an “obstetrical specialized” one (GoodRx).

At birth

You see for yourself. In a rare condition, a baby is born with outer genitals “that do not clearly look either male or female,” and only a team of medical specialists can assess it (MedlinePlus).

What about old wives’ tales?

They’re fun to try, but none has been shown to predict the sex:

• Heart rate. Ohio researchers reviewed 966 early scans, analyzed 477 from before 14 weeks and found “no significant differences” between girls’ and boys’ heart rates (McKenna and colleagues, 2006).
• The Chinese gender chart. Tested on 2,840,755 Swedish births, it was “no better at predicting the sex of a baby than tossing a coin” (Villamor and colleagues, 2010).
• Belly shape and morning sickness. In a Johns Hopkins study of 104 women, neither was “systematically related” to the baby’s sex (Perry and colleagues, 1999).
• Cravings. Sweet for a girl, salty for a boy? “There’s no scientific link to gender,” says Banner Health (Banner Health).
• The Ramzi method. It claims to read the sex from the placenta’s side on an early scan, but it “has not been confirmed in any additional studies,” Contemporary OB/GYN noted in 2020 (Contemporary OB/GYN).

Try them for fun in our boy or girl quiz.

How to choose

• As early as possible. If your doctor or midwife offers cell-free DNA screening, ask whether the lab will report the sex, or say if you’d rather not know. Boy or girl? What changes when you find out early weighs it up.
• On a screen, with your people. An elective scan, as a keepsake on top of your medical scans. Calls get surer as the weeks pass.
• Within your prenatal care. Ask at the anatomy scan. In England, check your hospital’s policy first.
• As a surprise. Wait for birth, or have the answer sealed in an envelope. How to plan a gender reveal party, step by step takes it from there.
• When answers clash. Tell your doctor or midwife before acting on either one.

Boy or girl at our Glendale studio

Our Gender Confirmation is a keepsake, not a medical exam: a 2D scan, “the classic black-and-white picture,” at our studio in Glendale, Los Angeles County. “We book from 13 weeks, and we’re surest from 15.” “If you can wait until 15, do: we’re more confident, and a second look is less likely.”

“When we can’t be sure, we say so, and you come back for a free re-check.” For a reveal: “Tell us it’s a secret before you lie down. The screens stay off, we find the answer, and it goes into an envelope nobody can see through.” The envelope is subject to availability, so ask for it when you book. From 16 weeks, you can also find out during 4D Bonding, if you’d like to know.

Already had a blood test? We don’t check or explain blood tests. If what we see is different from what you’ve been told, “we tell you what we see, and how sure we are.” What a result means is a question for your doctor or midwife. A visit with us doesn’t replace the anatomy scan or any appointment with your doctor or midwife. See how finding out works, the session for families who’ve been told and prices, or call (818) 243-7010.

Not sure which week you’re in? Enter your due date, and the planner shows which sessions are ready now and which open next. Whatever you type stays on your device.

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