Boy or girl: The most common gender prediction myths

It wasn’t too long ago that expectant parents had to wait until the birth to find out their baby’s gender.

Thankfully, advances in medical science including ultrasound scans and DNA testing mean that, these days, parents don’t have to wait too long to find out the answer to the question: boy or girl?

Yet despite this, there are still many myths surrounding how to find out a baby’s biological sex – many of them old wives’ tales with no basis in scientific fact.

Not only are these myths misleading, but they can also cause disappointment for expectant parents.  

In this blog, we look at when a baby’s biological sex is determined, the most common gender prediction myths, and why DNA testing is the only 100% accurate way of finding out the sex of an unborn baby.

When is a baby’s gender determined?

Although all babies start out looking the same in the womb, the genetic information that determines whether the baby will be a boy or a girl is in place from the moment of conception i.e. when the sperm fertilises the egg.

Out of the 46 chromosomes that make up a person’s genetic material, only two determine the sex of the baby – the X chromosome from the egg and the X or Y chromosome from the sperm.

If a sperm carrying an X chromosome fertilises the egg, the baby will be a girl. 

If a sperm carrying a Y chromosome fertilises the egg, the baby will be a boy.

This means that biological sex is set long before the first hospital appointments and ultrasound scans begin.

5 common myths about guessing a baby’s gender

Myths for guessing a baby’s sex before birth have been circulating for thousands of years.

However, while it might be fun to guess before the big day arrives, it’s important to take these theories with a pinch of salt.

This can help temper any disappointment if an ultrasound or DNA test reveals that the baby is not the gender you were expecting.

Here are 5 common myths about guessing the gender of an unborn baby that are still circulating today:  

The ring test…

Passed down through the generations, this classic old wives’ tale is not so much a test as it is a fun guessing game.

To perform the ring test, the mother lies on her back and another person dangles her wedding ring over the baby bump on a piece of thread.

If the ring moves back and forth over the bump, it’s said that the baby is a boy. If it moves in a circle over the bump, it’s a girl.

The chances of accuracy with this ‘test’ are around the same as flipping a coin but can be a bit of harmless fun – provided you don’t rely on the results when choosing décor for the nursery!

Watering the plants…

While pregnancy tests today are commonly performed using urine samples, the earliest recorded form of pregnancy testing using urine comes from Ancient Egypt.

During these times, it was thought that if you urinated on a handful of barley and wheat seeds, it could not only confirm a pregnancy, but also reveal a baby’s gender.

If the seeds sprouted, this meant the woman was pregnant. If barley grew, this was thought to signal a girl, while the growth of wheat meant the baby was a boy.

In 1963, scientists performed a study replicating this Ancient Egyptian method. It was found to be around 70% accurate when it came to predicting pregnancy, which could possibly be attributed to higher levels of oestrogen in a pregnant person’s urine, which can stimulate plant growth.

However, there was no evidence to support that this method could reveal a baby’s gender.  

Sugar and spice…

It’s completely normal for a pregnant woman to experience food cravings (and aversions). But some people believe that these cravings can be a tell-tale sign of gender.

It has been said that if mum is craving sugar, she could be expecting a ‘sweet’ baby girl. Conversely, a want for all things savoury, sour, or spicy is thought to signify a boy is on the way.  

There’s no scientific evidence to support this myth, as cravings can be caused by a variety of factors including mineral deficiencies and hormonal changes.

Baby bump shape…

A common myth that persists is that you can tell the sex of the baby from the shape of the mother’s bump.

‘Carrying low’ is a term that’s often used to describe the baby bump sitting closer to the hips. Historically, this has been thought to indicate a baby girl.

‘Carrying high’ i.e. having a protruding bump that is slightly lifted is thought to indicate a boy.

There is very little evidence to support this theory though, as baby bumps come in all shapes and sizes depending on a variety of factors including the mother’s age, build, core strength, and whether it’s the first pregnancy.

Additionally, mum’s baby bump tends to ‘drop’ towards the end of pregnancy, as the baby naturally moves into the right position for birth. This means that even a ‘high’ bump will likely become a ‘low’ one eventually.

Speed of the heartbeat…

This old wives’ tale is thought to have begun with the invention of the stethoscope, which meant that doctors could listen to the baby’s heartbeat for the first time.

A ‘strong’ or fast heartbeat was said to indicate a healthy baby boy, whereas a slower heartbeat could be attributed to a ‘delicate’ baby girl.

Over time this myth has been turned on its head, with a heartbeat below 140bmp said to belong to a boy.

However, there’s zero evidence for this. In fact, it’s more important that the baby’s heartbeat is consistent and not too fast or slow, as this is a good indicator of the baby’s health.

How can you find out a baby’s gender before birth?

Although pregnant women will sometimes (rightly or wrongly) have a sense of whether an unborn baby is a boy or a girl, the only 100% accurate way to find out a baby’s gender before birth is with a DNA test.  

While a qualified sonographer may be able to provide an answer during an ultrasound appointment – usually from around 20 weeks into pregnancy – this is not always accurate.

This is because it is not always possible to see the baby’s genitals clearly in the womb, depending on how the baby is lying on the day of the ultrasound.

However, the way in which foetal DNA is passed into the mother’s bloodstream means DNA analysis can be used to determine the sex of an unborn baby with a higher degree of accuracy.  

A prenatal gender test or baby gender test, such as those performed at AlphaBiolabs, is a 100% accurate, reliable way of determining whether the baby is a boy or a girl.

The test can be performed from as early as 8 weeks into pregnancy and simply requires a blood sample from the mother.

When this sample is analysed in the laboratory, expert geneticists can determine whether the baby is a boy or a girl, by looking for the presence of a Y chromosome in the mother’s bloodstream – a clear indicator that the baby is a boy.

If no Y chromosome is present in the mother’s bloodstream, then the baby is a girl.

Where can I buy a baby gender test?

For just €249, with FREE sample collection at our Dublin walk-in centre, our Baby Gender Test can determine whether an unborn baby is a boy or a girl from as early as eight weeks into pregnancy.

With only a blood sample required from mum, the test is completely safe and risk free for mother and baby.

Order your test online now for results in 7 days, or upgrade to our 4-day express service for an extra €60.

Got a question about this test? Call our friendly and knowledgeable Customer Services team on 01 402 9466 or email info@alphabiolabs.ie.