There are dozens of old wives tales which try to predict your baby's gender, yet mums swear by this newest technique 'Skull Theory'
Expecting mamas are uploading scan photos to try and get the internet to guess if they're having a boy or a girl with a quick analysis.
Traditional medical scans won't determine whether a baby is male or female until 20 weeks - but some experts think it is possible to predict the foetus' sex at 12 weeks...
What is skull/nub theory?
Apparently, it's super easy to tell by analysing the skull shape and ‘nub’ area between the legs.
Boys predominately have squarer chins, a chunkier skull shape and more pronounced brow ridge, whereas girl’s skulls have a smaller brow ridge and more pointed chins.
Babies with a ‘nub’ – or genital tubercle – angled at greater than 30 degrees are likely to be boys, while girls' nubs sits below 30 degrees.
Some experts claim up to 88% accuracy using the technique - making it more effective than the 75% of parents who said their 20-week scan correctly predicted their baby’s sex.
According to a study by parenting site ChannelMum.com, 45% of pregnant women now take part in the phenomenon known as the ‘nub and skull theory’.
WATCH: ChannelMum discuss the nub and skull theory
ChannelMum.com gender expert Lisa Lum said: "The Nub and Skull theory is the fastest-growing gender prediction technique simply because it’s so social.
''Three-quarters of mums who try it say they like getting other people’s opinions on their child’s sex while 30 per cent see it as a worldwide craze they like to be part of.
''While no non-medical technique is 100% accurate, it’s fun and brings people together, which is exactly what children should do at all ages."
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