You’re all excited for your 20 week pregnancy scan and you hope to find out whether it’s a boy or girl in there!
The sonographer gets the wand into position and… the baby’s legs crossed during ultrasound!
Despite all the jiggling, walking and pleading, you can’t get a good enough look to find out your baby’s sex.
How can you tell if a baby is a boy or girl on an ultrasound?
The sex of your baby is decided the minute sperm fertilises egg.
During the first stages of embryo development, you can’t tell the difference between boys and girls.
All babies in the embryonic stage have a small nub that develops either into a penis and scrotum for boys, or a clitoris and labia for girls.
This process takes about 12 weeks before it becomes obvious and even then it’s quite difficult to visually tell the difference.
By the time your baby is 20 weeks and you’re having your mid-pregnancy check-up, your baby’s sex is much easier to detect on ultrasound.
In fact, research shows after 14 weeks gestation, sonography prediction is 100% accurate.
Boys have a nub that will point upwards at an angle of more than 30 degrees from their spine. In girls, the nub is more horizontal and sits at an angle of less than 30 degrees.
You can see all this, as long as babies are in a good position and their legs aren’t tightly closed or crossed.
What does it mean when babies cross their legs?
Often babies will find the most comfortable position in the womb is with their legs crossed.
I don’t know if we can take it personally. After all, they have no idea we’re outside with special equipment, trying to peek in.
Apparently, there’s a theory out there: babies who have their legs crossed during the 20-week scan are girls.
There’s absolutely no evidence to prove this, and it definitely shouldn’t be used as a means to work out your baby’s sex.
Why are baby’s legs crossed during ultrasound?
Perhaps the baby is shy. But, honestly, babies really have no concept of being spied on when the ultrasound equipment is turned on.
It’s hard to know the ‘why’, but some babies have a personal preference for comfort.
At 20 weeks or thereabouts, babies are still small enough to move their limbs about. They often enjoy performing all kinds of acrobatics in there.
They can even shift from head up to head down relatively easily.
Most babies lie with their back towards their mother’s belly, with their legs folded up towards their chest.
This position might be much more comfortable. And that’s why baby’s legs crossed during ultasound.
How to get baby to uncross legs during an ultrasound
You’re lying on the ultrasound table. Your shirt is pulled up and the cold gel is drying on your belly. The sonographer is moving the wand around but your baby isn’t in the mood to cooperate.
How do you get your baby to uncross those legs during an ultrasound?
If you suspect your baby is asleep in that position, you could try a wake up call – coughing, laughing or making a loud noise.
The sonographer might try prodding or gently shaking the baby with the wand. You could also try using your hands to jiggle or shift baby.
Sometimes getting off the table and doing some high steps can jolt baby out of his(?) her(?) slumber.
How can I get my baby to move before an ultrasound?
If you think your baby is going to be uncooperative before your ultrasound, try these tips just before you go into the sonography clinic:
- Drink ice-cold water
- Lie on your left side for as long as possible
- Drink something sweet, like fruit juice
- Walk up and down the stairs
- Use a handheld massage tool that vibrates on your belly.
You might just have to be patient and wait for your baby to move.
It’s frustrating, but the surprise of finding out what sex your baby is at birth will be really exciting.
Should I have another ultrasound if baby’s legs crossed during ultrasound?
It’s not recommended to have ultrasounds for anything other than medical reasons.
The 20-week scan is also known as the morphology scan and is a routine check-up to make sure all is well with your baby.
At 18-20 weeks gestation, your baby’s limbs and internal organs are easily visible on ultrasound. The sonographer will check:
- Fetal heart rate
- The size of your baby
- Whether there’s more than one baby
- The position of the placenta
- How much amniotic fluid there is
- Whether there are any abnormalities.
If you don’t need to have another ultrasound, you might have to wait until your baby is born to find out the sex.
Although ultrasounds are considered safe, there are still protocols and guidelines about their use. Continuous or long term unnecessary exposure to ultrasound waves might be risky.
You can read more in Ultrasound In Pregnancy – Risks and Benefits.