Boy or girl? Try these gender prediction methods (2024)

There are several proven ways to find out your baby's sex. But if you want to try to guess in the meantime, there are plenty of old wives' tales – and a few research-related theories – that may predict whether you're having a boy or girl.

Just keep in mind that much of the scientific evidence is slight, and the old wives' tales are just superstition. But at the very least, you'll have a 50% chance of being right!

Signs you're having a boy

You may be slightly more likely to be carrying a boy if:

You were having lots of sex when you conceived

Frequent sex may give male sperm a slight advantage.

Why? Male sperm are lighter and have smaller heads and shorter tails. This allows them to swim more easily through the mucus in your vagin* at the beginning and the end of your fertile window. Some experts think that female sperm are more likely to reach the egg in the middle of your fertile period.

So if you're having frequent sex, you have higher odds of having sex during both the start and end of your fertile window, giving male sperm a slight advantage.

Learn more about the best time to have sex to get pregnant.

This is your third (or later) pregnancy

A studyOpens a new window of more than 11,500 births in Poland found that the likelihood of having a male newborn increases by 20% in the third pregnancy compared to the first pregnancy. For each pregnancy following the third, there was a higher probability of having a boy compared to the first pregnancy.

Your partner has more brothers than sisters

One studyOpens a new window suggests that men may inherit a tendency to have more sons or daughters from their parents. Since Dad's sperm decide the sex of the baby, your partner may tend to have more boys or girls, depending on whether he's inherited more X or Y chromosomes. So if your baby's dad has lots of brothers, you may be bringing another boy into the family.

You gain more weight during pregnancy

One studyOpens a new window divided 740 British women into groups according to their caloric intake. Of the women who had the highest daily intake, 56% had boys. Of the women who had the lowest intake, only 45% had boys.

Another studyOpens a new window looked at 68 million births globally and found that women who gained more weight during pregnancy were more likely to be having boys. One factor may be that baby boys tend to be bigger than girls.

Some researchers theorize that male babies are more fragile and are statistically less likely to be conceived or survive pregnancy when times are challenging – such as when food is in short supply. Baby girls are hardier early in pregnancy, they say, so in leaner times they may be more able to survive.

You conceived in the summer

In some countries, more boys are conceived in the summer and more girls are conceived in winter. Relying on the theory that male babies may be more fragile than female babies, researchers theorize that more males survive when conceived during the summer or early autumn when conditions are most favorable – there's plenty of exposure to vitamin D from the sun and a range of seasonal foods available, for example.

Other expertsOpens a new window theorize that the balance may be tipped because of seasonal viral and bacterial infections. Male babies may be less able to withstand their mom catching an infection in winter, for example.

You're past your due date

Moms who give birth to boys tend to have slightly longer pregnancies. According to a studyOpens a new window of more than 656,000 pregnancies, male babies had longer gestations, making them more likely to go past the due date.

You have gestational diabetes

Some studies show that women carrying boys have a higher risk of developing gestational diabetes – though the reason why isn't clear.

On the other hand, women with diabetes before pregnancy deliver the fewest boys. According to one studyOpens a new window, this may again be related to male babies being less able to withstand challenging conditions.

Signs you're having a girl

You may be slightly more likely to be carrying a girl if:

You suffer badly from morning sickness

You're slightly more likely to have a baby girl if you have severe morning sickness (hyperemesis gravidarum). A reviewOpens a new window of 13 studies found that 55% of babies born to women who'd had severe morning sickness were girls.

Some experts believe that mothers of girls tend to have higher levels of hCG, the pregnancy hormone that may be linked to morning sickness.

It's very hot – or cold – where you live

A studyOpens a new window of Japanese births from 1968 to 2012 found that more girls were conceived during a particularly hot summer in 2010, and again during an extremely cold winter in 2011.

Other research has shown that warm temperatures and girl babies are linked. One study found that more girls are born in the tropics (the region around the equator) than anywhere else in the world.

One theory is that weather extremes cause stress. In addition to the uncomfortable temperatures, very hot or cold places tend to have poor nutrition, high levels of pollutants, and insufficient or excessive sunlight. Such stress is especially hard on male babies, who are possibly more fragile than females in the earliest months of pregnancy.

Your partner has more sisters than brothers

Dads may inherit a tendency to produce more girls than boys (if their sperm contains more X chromosomes than Y chromosomes). If there are more sisters in Dad's family, you may be more likely to be carrying a girl.

Your job is stressful

Women working in mentally stressful jobs outside the home may be more likely to have a girl. According to one studyOpens a new window, women in high-stress jobs were more likely to give birth to girls, while women in low-stress jobs weren't.

Another studyOpens a new window found that women who gave birth to girls had higher levels of cortisol (a stress indicator) in their hair samples before and during conception.

ResearchersOpens a new window point to a pattern of fewer boys being born during times of stress, such as after earthquakes and the 9/11 attacks in New York City. They suggest that male babies are less likely to survive in poor conditions than females.

You conceived after hormonally induced ovulation

Some studiesOpens a new window carried out among women who used hormones to induce ovulation show that you're slightly more likely to have a girl if artificial hormones such as clomiphene (Clomid) are involved. However, other experts aren't convinced.

What about heart rate gender prediction?

You may have heard that if your baby's heart rate is less than 140 beats per minute, you're having a boy, and if it's more than 140 beats per minute you're having a girl.

But researchers have debunked the heart rate gender prediction theory. A reviewOpens a new window of 223 articles on the topic concluded that any sex-related difference in fetal heart rate is minimal and, if anything, shows boys with a faster fetal heart rate than girls.

A normal fetal heart rate ranges from 110 to 160 beats per minute and can vary by 5 to 25 beats per minute. It may change as your baby responds to conditions in your uterus.

Old wives' tales about gender

When it comes to gender prediction, there's no end to superstitions. Some are based on how you look, some on how you're feeling or what you're craving, and some on, well, you name it!

Your pregnancy symptoms

Heartburn

Having lots of heartburn during pregnancy? You may be having a girl, according to one tale. According to another, heartburn means your baby may have a lot of hair.

Of course, heartburn during pregnancy is very common whether you're carrying a boy or a girl.

Food cravings

Food cravings are real – but do they reveal anything about your baby?

Some tales say if you're eating lots of salty snacks, you're having a boy, and if you're craving sweets, you're having a girl, while others claim the opposite.

Researchers haven't been able to link specific cravings to a baby's sex. They suggest pregnancy cravings have other drivers, such as hormonal changes, nutritional deficits, food ingredients, and cultural factors.

Another myth relates to Dad's snacking: It says if the father gains weight during your pregnancy, you're having a girl!

Energy level

According to one myth, a boy baby will make you more tired (and clumsy), while a girl will give you more energy and keep you alert.

Sleeping preference

Prefer sleeping on your right side? Supposedly you're having a girl. If you prefer your left, you're supposedly having a boy. (Of course, your preferred sleeping position is likely a combination of how you've always slept and what's most comfy as your belly grows.)

Conception environment

Old wives' tales say:

• If you conceived after midnight, you'll have a girl.
• If you conceived during the new moon, you'll have a boy.
• If your partner looked at the full moon over his right shoulder while you were making a baby, you'll have a boy.

Your appearance

The tallest tales seem to relate to Mom's appearance during pregnancy. For example:

According to some old wives' tales, you're having a girl if:

• You're looking less beautiful. (Apparently your girl baby has swiped your looks!) Your pregnancy hair and nails may be dry, you may have oily skin and acne, and your face may be fuller and rounder.
• Your linea nigra (the dark line on your pregnant belly that travels down to your pubic bone) starts below your belly button rather than above it.
• Your pregnancy weight gain is spread throughout your body.

According to some old wives' tales, you're having a boy if:

• You're more beautiful. Your skin is glowing, and you have shiny, healthy hair and healthy nails.
• Your linea nigra starts above your belly button.
• You have swollen feet.
• Your pregnancy breasts are larger and heavier, with darker areolas.
• Most of your weight gain is in your belly.
• Your butt is bigger and rounder.

How you're carrying

How you carry your baby depends on how far along you are in pregnancy, the shape of your body, the size of your baby, and your baby's position (if they're lying sideways, you'll be wider, for example). Still, the myths prevail. According to lore:

• If you're carrying low in your abdomen, you're having a boy.
• If you're carrying your baby high (your bump is up near your rib cage rather than lower down), you're having a girl.
• If your belly is sticking straight out (protruding out in front rather than spread side to side), you're having a girl.

Remember that all these gender prediction methods are just for fun – much like these gender predictor tests and our Chinese gender predictor. Hold off on making any gender announcements and don't buy any gender-specific baby items until you get official confirmation of your baby's sex.

Note:We've used the words gender and sex interchangeably in this article because people often do. However, the two terms are not the same. Sex is assigned based on biological characteristics, such as genitals. This may not match the gender identity(based on feelings and behaviors) a person assumes later.