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birth-planning

Nub theory

What it is

Can the nub theory show the sex of my baby?

Some parents-to-be are desperate to find out the sex of their unborn baby as early as possible, and will search for clues at the very first scan. Which is pointless, isn't it? Everyone knows you can't tell the baby's sex at the 12 week (or there abouts) dating scan. Or can you?

At a glance

  • The nub theory searches for clues at the first scan
  • The theory says that the genital tuber will stick up for boys and out for girls
  • Your baby needs to be in a very good position for you to see this part of them

Well, some people think you can, thanks to a little known phenomenon called the 'nub theory'.

How does it work?

The nub theory works on the basis that from 12 weeks, boys' genitals (or the genital tuber, as they are not actually properly shaped bits and pieces at this stage, and both sexes will have a little tube- like protrusion) will be angled differently to a girls', and so by carefully examining your scan picture, you can work out the sex.

What the experts say

Experts in the theory reckon that if you are having a little girl, the tuber will be sticking out horizontally, while if you are expecting a little boy, their 'nub' will be pointing upwards (it might help you make comparisons if you compare your scan pics with those of a baby who has already been born, or whose sex is known).

How can they tell?

Of course, in order to even see this part of your tiny baby on the scan, they need to be in a good position when the sonographer captures the images – if your little one is wildly kicking their legs or turned away from the sonographer's equipment, then you might not see that part of them at all.

How reliable is the theory?

There is no firm scientific research to bear the nub theory out, and it is very unlikely the person carrying out your scan will be drawn on it (or your findings!) but many mums swear it is accurate – and obviously as a bit of fun, can do no harm! (just don't buy your baby's entire wardrobe based on your conclusions!).

So what do you think about the nub theory? Chat to other mums on Bounty.com in the community.  

At a glance

  • The nub theory searches for clues at the first scan
  • The theory says that the genital tuber will stick up for boys and out for girls
  • Your baby needs to be in a very good position for you to see this part of them
Many mums swear the nub theory  is accurate – and obviously as a bit of fun, can do no harm! 

Nub Theory