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Nub Theory is a fact, You can't argue with science when done correctly!

Photo credit - science source


This way has up-to 99.9% accuracy*

You won't believe it, but I can assure you that this isn't just some run-of-the-mill theory. It's an actual science-backed method of determining the gender of a baby from a side profile view, known as the mid-line sagittal view. Forget about trying to peek between the legs before the 20-week mark – this way is much more accurate!


Let's dive into the fascinating details. When you're around 11-13 weeks pregnant, you'll undergo a dating scan that helps determine the accurate timing of your pregnancy. This timing is crucial when utilizing the nub theory. Surprisingly, nubs, which indicate the baby's developing genitalia, are visible as early as 9 or 10 weeks. However, they haven't started to change from their initial "female state" at this point.


It's during the late 11th to 12th week of gestation that the hormones kick in and trigger the development of your baby's genitals. For boys, testosterone comes into play, transforming the nub into a scrotum and penis. Meanwhile, girls experience the development of labia and clitoris.


Now, for the peak of accuracy, Is 13+ weeks. However, exceptional accuracy can already be achieved in the 12th week especially when a boy is already developing (I'll explain all the details in your reading if applicable).


So, what's my role in all this? As I assess your images, I'll meticulously examine the appearance of your baby's developing genital nub. I'll consider factors like the shape, size, length, angle, and even the bladder(if imaged) to provide you with a predicted gender result.

its not always about the "angle of the dangle" that's is proven to be a myth! its about the appearance!


Forget about those old wives' tales like low baby bumps indicating a boy or sweet cravings suggesting a girl. Only the nub theory can effectively and accurately reveal the gender of your baby, with an astounding accuracy rate of up to 99.9% when considering the gestational stage or gender detected!


Now, let's get into the anatomical changes that occur during the twelfth week. The labioscrotal folds, previously enclosed within the genital tubercle, begin to separate. In male fetuses, the scrotum descends below the penile bump, while the bump itself moves away from the rump. In females, the labia start forming around the clitoral protrusion.


However, don't be mistaken – these changes don't mean that by the end of the twelfth week, the baby has fully developed genitalia. Both the clitoris and penis still protrude between the legs in a similar length, making those "potty shots" unreliable at this stage.


Studies have shown that during the twelfth week of gestation, the accuracy rate is around 90%. However, these studies were conducted using live sonography scans, enabling various angles and accurate spine positioning. The accuracy rate increases to an impressive 92-98% when clear still images of the nub and spine are available, taken between twelve weeks and four days and twelve weeks and six days, and then 99.9% after 13 weeks. or boys seen!


This is why providing the exact age and all your scans and videos, if you have them, is of utmost importance. The nub theory is based on the baby's measurements on the day of your scan. Look for the gestation based on the CRL (crown to rump length) – you might find it printed on your scan or in your maternity notes, such as "12w 3d" or "13w 2d" (weeks and days).

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