How to Know the Sex of Your Baby During Pregnancy

So you’ve taken the test – it’s positive. You’ve gone to the OB-GYN – the embryo’s developing. You’re officially pregnant! That leaves the next big question for moms: will it be a boy or a girl? It’s possible to know your baby’s sex well before your due date, and your friends may be curious as well. So what are the ways to determine a baby’s sex in utero? Let’s run through the basics of how and when you’ll find out.

How early can I know the sex of my baby during pregnancy?

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The sex chromosomes of your child are locked in at the moment of conception: XX (genetically female) or XY (genetically male) . However, all embryos appear to be genetically female up until Week 7. This is because at this stage, the embryo has not started to develop differentiated gonads (testes or ovaries).

If the baby has XX chromosomes, the indifferent gonads develop into ovaries around Week 10. If the baby has XY chromosomes, the testes will start developing from around Week 7. It takes several weeks for this process to be complete, so the difference between male and female generally becomes apparent only around Week 12.

How soon can the baby’s sex during pregnancy be determined?

baby boy girl

Your morning sickness will likely begin to subside as you head into the second trimester of pregnancy after Week 14. It’s also around this time that some moms start to feel a hunch or gut feeling about their child’s gender. However, even a mother’s intuition can be mistaken! You’ll still need to wait a little while longer before your baby’s sex shows up on an ultrasound.

Your sonographer will be able to tell you to expect a boy or girl from as early as Week 16 or 17, but more commonly, this happens between Week 18 and 19. After Week 20, the shape of the fetus’ genitals is quite readily apparent on an ultrasound scan, though in some cases there might be some vague indications from as early as Week 12 to 14. Every pregnancy is different, so you’ll know when the time comes!

How is the baby’s sex determined?

pregnant woman ultrasound Scan

Your sonographer will usually be able to determine the sex of your baby during your mid-pregnancy through an ultrasound. However, this might not be possible if your baby has their back or butt to the camera, or if they are covering their lower body with their hands or legs. Try not to be too disappointed if you can’t find out the sex of your baby at this time. After all, the main purpose of this ultrasound is to check that your baby is developing healthily – not to see if you’re having a boy or girl.

Internal sex organs can sometimes be distinguished

The ultrasound exam usually distinguishes between the sexes based on external genitals, but in some cases, the internal sex organs can also be identified. If the fetus is physically male, the ultrasound will show a single dark blotch on the lower abdomen. This shows where the urinary bladder is growing. If the fetus is physically female, there should be two blotches there: one for the bladder, and another one for the uterus.

No 100% sure way to know gender of baby during pregnancy

pregnant woman

It’s understandable to want to know about your baby’s gender. Some moms might be hoping for a little boy or a little girl, but many would simply like to know in advance so they can prepare themselves for maternity a little better.

But for all our modern imaging technology, there can still be surprises: sometimes you do hear stories about kids who looked like a girl in the ultrasound imaging, but who turned out to be boys. Even after birth, there’s also a chance that your child could grow up to identify as transgender, or non-binary.

Taking all this into account, there’s no way to know your child’s gender during pregnancy with 100% certainty. However, no matter what gender your child turns out to be, the most important thing is for your baby to know that their Mom and Dad will always love them, no matter what.