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How to predict gender from ultrasound

There are multiple ways of determining your baby’s gender when in utero.

1/ NIPT (blood test)

It is possible to opt for a NIPT (non-invasive prenatal test) at 10 weeks these are 99% accurate in predicting bub’s gender in addition to providing you and your health team with any important genetic information about your unborn baby including abnormalities, particularly Down syndrome

2/ The ‘Nub’ theory

The genital tubercle or the 'nub’ can be visualized at your 12-14 week ultrasound. Both boys and girls have a nub.

To all the dads out there no, this is not necessarily a penis.

The theory goes that if the nub is pointing up less than 30 percent from the spine, ie, more parallel with the spine, it’s a girl.

If the nub points up more than 30 per cent, it’s a boy.

From an experienced sonographer take it from me the ‘nub’ theory is flawed. There is just too much room for error. FYI don’t go asking your diagnostic Sonographer to get the protractor out and start measuring nub angles, they are more concerned about the presence and condition of your baby’s vital organs.

3/ Hamburger or maraca method

Although viewing your baby on ultrasound may look more like watching an underwater sea monster swimming around than a mini human being, determining your baby’s gender is relatively straightforward.

If there’s a clear ‘ between the legs’ view, you may be able to spot either a hamburger or maraca (really!) That’s all your ultrasound technician is looking for when checking bub’s gender.

A ‘hamburger’ sign will generally mean it’s a girl. The shape of the labia creates three bright lines, these look like a little hamburger .

For a boy, you’ll see a ‘maraca’ shape, which is the penis peeping ever so slightly from behind the testicles.

Its relevant to mention that some cheeky bubs love to cross there feet in front of their genitals and the umbilical cord also often like to float about down there obstructing your Sonographers view.

Here at Hinterland Ultrasound we love dedicating our expertise in determining your babies gender this is generally best indicated after 16 weeks.

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