Nub Theory: ‘Nub-sessed’

‘The Angle of The Dangle’.

Nub Theory: Numerous studies published in medical journals have assessed thousands of pregnancies to determine that the angle of the genital tubercle can predict gender in the first trimester very accurately from the 12th week.

Endless online searching can make the most sane mother-to-be feel crazy!, hence the term ‘nub-sessed’.

The following images are from 12-14 weeks ultrasound scans. The two images below are profile shots of the scan and at this age of gestation the best view of the nub, Therefore when submitting your image ensure the scan is a profile image.

Image 1: Male fetus in early development. With the male fetus, the genital tubercle usually creates an angle of greater than 30° with the lower part of the spine.

Boy Nub Theory Image


Image 2: Female fetus in early development. In the female fetuses, the genital tubercle protrudes in the same direction as the lower portion of the spine with an angle of less than 30° relative to the backbone.

Girl Nub Theory Image


Studies have been conducted in Brazil, London (2 studies) and Israel. Out of a total of 1619 pregnancies; gender was assigned and confirmed in 1424.

The accuracy of the Nub Theory on weeks gestation:

11 weeks 68%
12 weeks 88%
13 weeks 94%
14 weeks 98%

As a result of the accuracy the Nub Theory is the favourable of all gender theories.

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