Nub Theory: The simple trick to predict your baby’s gender at just 12 weeks from ultrasound pictures

FOR expecting parents waiting until the 20-week scan feels like a lifetime.

This is because many want to find out if they’re having a baby girl or boy – but did you know there’s a theory that suggests you can predict your child’s gender at the 12-week scan.

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The nub theory is based on predicting a child’s gender at just 12 weeks[/caption]

What is nub theory?

The nub theory, also known as the angle of the dangle, looks at how your baby’s spinal cord and genital tissues are forming at your first pregnancy scan.

The idea behind nub theory is that if you can get a really good look at this nub, you can figure out which way it will go in the coming weeks.

According to proponents of nub theory, you can crack the code of your baby’s sex at a 12-week ultrasound.

While it’s not recommended by midwives – the NHS recommends you wait until your second ultrasound between 18 and 21 weeks – many parents say they’ve used the nub test to make an educated guess earlier.

Mum Clementine Salmon told The Sun: ”The one thing I firmly believe in is the ‘nub’ test.

“As this is my third pregnancy I compared all three 12-week scans and all had the nub at the same angle.”

How can you predict gender from a 12 week ultrasound scan?

To actually apply nub theory to your baby’s ultrasound, you need to catch them in a clear profile so the length of their spine is visible horizontally.

From there you would search for the nub, or a small protrusion, in between where your baby’s legs will form.

Becky Rutherford, a midwife sonographer, wrote for Baby Centre: “The sex of your baby is fixed at conception. All embryos have a small bud or swelling (genital nub).

“If you’re having a boy, testosterone starts being produced at seven weeks.

“Testosterone prompts the bud to grow and develop into a penis and scrotum. In a girl, the genital nub will become the clitoris and labia.

“Nub theory is based on the idea that it’s possible to tell which type of genital nub your baby has from the dating scan image.

“But nub development is a gradual process, and it’s a real challenge to see which way the nub is developing around the time of your dating scan.”

The angle of the nub can supposedly tell you the sex of your baby.

If the nub is angled higher than 30 degrees in relation to its spine, that indicates your baby is a boy, according to nub theorists.

But if the nub is pointing straight out, under 30 degrees, or down, it is likely a girl.

It might seem like a fool-proof way to tell the sex of your little one, but midwives and other doctors recommend you wait until your second ultrasound, typically at 20 weeks, to be certain.

That’s because it’s incredibly difficult to determine the sex of your baby in the first trimester as the genitals haven’t formed properly yet.

The main reason your second scan is done between 18 and 21 weeks is to check for physical abnormalities in your baby, but you can also ask the sonographer to check if it’s a boy or girl.

Don’t forget that it’s not an exact science – the sonographer won’t be able to 100 per cent know the sex of your bundle of joy.

If your baby is lying in an awkward position or moving around a lot, it may be difficult or impossible to tell whether your baby is a boy or girl, for example.

Some hospitals even have a policy to never tell expecting parents what the sex of their baby is – as there is still room for error even later in the pregnancy.

If your hospital has that policy you can always pay for a private scan to find out, but remember that it may still be wrong.

Let’s face it though, as long as your baby is born happy and healthy you’re going to be over the moon, no matter if they are a boy or girl.