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Does The Nub Theory Really Predict Your Baby's Gender At Just 12 Weeks?

the nub theory girl or boy

Is curiosity getting the better of you? Baby Girl or Baby Boy on the way? The nub theory has been studied for many years and because of its huge accuracy its widely becoming the number one early gender predictor across the world. 

THE NUB THEORY EXPLAINED

The nub theory is a medical term used by healthcare professionals to identify the baby's gender from around 12 weeks in gestation.

 

The nub (Genital Tubercle) is your baby's developing genitals, so no theory over here.

 

All nubs will image as a fork. This fork is split into two parts. The bottom half, also known as the urogenital folds will develop into the labia minora, and the top half known as the genital tubercle will develop into the clitoris. By 11 weeks of gestation, the clitoris is prominent and the lateral boundaries of the urogenital sulcus have separated.  For male fetus the genital tubercle will develop into the glans of the penis, the urogenital fold becomes the shaft and the labioscrotal fold matures into the scrotum.

NUB THEORY TRUTHS

SCIENTIFICALLY PROVEN

The nub theory is  proven to be the most accurate form of early gender prediction today. Now backed by science. The nub theory is one of the most talked about theories across the internet. However, unfortunately some will still argue that the nub theory is just a myth or 50:50. This is simply not true. Depending on who is analysing your scans and the experience they have, will ultimately lead to the prediction being correctly identified or not. For example, most companies will see a "stacked nub" and instantly predict that the baby will be male, however the angle plays a huge part in this analysis and if the nub appears stacked but the angle is parallel then the baby is female. (stacking does not mean boy!)

the nub techs

SO WHAT IS A NUB?

A nub is your baby's genitals in development. The genital tubercle bump (nub) will start to develop from around 8 weeks in gestation, this can be seen via ultrasound from as early as 9 weeks. However, accurately assessing your baby's nub is not reliable enough until the 12th week. All babies will have  a nub between their legs, the angle of the nub, will indicate whether your baby is a boy or a girl. If your baby's tubercle is pointing at a caudal angle (downwards towards the rump) and less than 30 degrees to the axis of the dorsal surface (baby's back/spine), this would indicate your baby is  female. If the tubercle is at a cranial angle (upwards towards the cranium) and at an angle greater than 30 degrees to the axis of the dorsal surface, this indicates your baby is male.

stacked boy nub

NUB

HOW CAN YOU TELL THE DIFFERENCE - BOY OR GIRL NUB?

NUB THEORY BOY

ultrasound nub theory

STACKED, SHORT AND BULBOUS NUB

The developing boy nub you see below is above a 30 degree angle, he is also showing full scrotum and penis in development. You will notice the nub is shaped with a short white line with a very visible white bump on the top.

NUB THEORY GIRL

ultrasound shows a girl

LONG, FLAT AND TUBED NUB

The developing female nub varies at different gestations, the nub here is parallel to her spine, it also sits below 30 degrees and you will also find her nub hangs directly off her rump.

DOES A FORKED NUB MEAN GIRL?

So we often get asked, if a nub is showing as a fork it has to be a girl, is this right? This information is actually incorrect. The length and shape of your baby's nub may sometimes indicate gender, but not always.For example, some say that a “forked nub” is indicative of a girl fetus, however we do not adopt this, as its clear that both sexes can be seen with a forked nub in the early stages of development.  The reason you see a fork shaped nub in both female and male fetuses, is because this fork serves an important purpose. For females, this fork will become the labia and clitoris, for males, the top half of the fork will develop into the penis, and bottom fork into the scrotum.We also know a forked nub is a sign of an undeveloped nub or a late riser (in males)

DOES THE ANGLE OF THE DANGLE REALLY MATTER?

The nub theory is extremely accurate when analysed correctly. The angle of the dangle plays a huge role in determining your baby's sex. Spine, bladder and the nub should be used for the determining factors.

A Baby Boy - The nub is over 30 degrees or over 

 A Baby Girl - The nub is between 10-29 degrees

nub techs ltd boy nub
the nub techs forked girl nub

WHAT IS A STACKED NUB?

The "stacked" nub as it's most commonly known consist of the developing penis and scrotal line. Both can be seen imaging in bright white at the base of baby's body. The penis is seen as a round shape, while scrotal line is located right underneath and longer in length  this images as a short line (but not always)

Female nubs can sometimes image in funny ways too, this makes them appear as "stacked". This happens when the top part of the fork on baby's nub, also known as baby's clitoris has been captured at an off angle. These angles can often lead to much confusion and wrongful prediction of baby's sex in the nub theory community. 

ultrasound using nub theory

GENITAL TUBERCLE AT 12 WEEKS

the nub techs

THE SCIENCE BEHIND THE NUB THEORY?

Several scientific studies have been used to analyse the accuracy of the nub theory, the first one back in 1989. After the last 30 years these scientific studies have shown that the nub theory has an accuracy of around 90%. However, we know that this stands at a higher percentage when baby's gestational age is 12.5 weeks and above and their nub is fully imaged during scanning.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5024945/

the nub techs nub theory

FULL NUB

IMAGING

BABY BOY

NUB THEORY DEVELOPMENT STAGES?

We know that all baby's are different and so is their development rate in the womb. Some male baby's in the 11th to the early 12th week can develop more rapidly than others, the term "early boy" is used to describe this. At the end of the 11th week going into the beginning of the 12th week most nubs will image parallel and the term used for this is "early girl".  From 12.5 weeks to 13 weeks (a matter of a few days) a nub can image parallel, but develop that little bit later and be confirmed boy, this happens in around 6% of  baby's and the term used is "late riser".

 

When analysing your baby's nub there is much more that goes into it than just the than just the angle. We take into account your baby's gestational age, this being the most important factor, bladder position, this helps us identify the correct angle in which your nub points too. Your baby's spine, if this is curved or straight, depending on how your baby has imaged in the womb during scanning. The appearance of your baby's nub, they can image in several ways, your baby's legs (the positioning) if and where they are located and so much more.

the nub theory explained

CAN IT BE TRICKY TO DETERMINE THE GENDER?

Sometimes, yes! When your baby moves around, jumping and dancing in the womb their nub can image in different ways....The angle and the appearance of the nub can look totally different, one shot may show a clear girl nub then the second shot may look to an untrained eye as boyish. For instance the nub below had many boy predictions because it looked "stacked". but the angle of the nub was still below 30 degrees and the nub was parallel to the spine.

girl nub theory at 11 weeks

BABY GIRL

SAME BABY

boy nub confirmed  girl

IDENTICAL LOOKING NUBS - BOY OR GIRL?

my nub looks girly

FORKED GIRL NUB

When drawn correctly these nubs will show an angle of less than 30 degrees and an angle above 30 degrees. So many believe that a forked nub instantly means it's a girl but this is not true.

forked nub mean girl

FORKED BOY NUB

DO SOME BABY'S IMAGE WITH NO NUB?

Yes, unfortunately your baby may show no signs of gender markers, don't panic if this is the case for you. This just means your baby's nub didn't image when the sonographer took the picture of your baby. Unfortunately though your baby's prediction is basically 50:50. Our techs will always let you know if this is the case and refund you in full. However, unfortunately some companies will provide you with a false report so please be careful of this. Always ask before purchasing.

 

Below you will see an ultrasound of a baby showing no nub.

baby ultrasound

WHY THE NUB TECHS ARE THE MOST ACCURATE GENDER PREDICTION TO USE

The nub techs are the most trusted and reliable gender prediction company out there, our trust pilot, instagram and facebook reviews speak for themselves. We have predicted for many celebrities and bloggers across the world and continue to prove far and wide how the nub theory really is the most accurate way of learning your baby's sex from just 12 weeks.

NUB THEORY DRAWINGS

When we draw your baby's nub, we draw each one individually, we start at your baby's face, then the body, the nub and then all the extras like cord and leg that image too. Visually we try and give you a real life view of exactly how baby was captured during scanning. We have been asked on occasion if a computer draws your baby, the answer to this is absolutely not. We have added a video below to show you how we work. 

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