During pregnancy, you may get compliments that you’re “glowing.” This refers to a phenomenon that’s often visible on the face during pregnancy.

This can be a very real part of pregnancy and it may occur for a variety of reasons. While the term itself sounds like a myth, “pregnancy glow” actually has several medical explanations. Let’s demystify exactly what pregnancy glow means and whether there’s anything more to it.

According to stories going back centuries, pregnancy glow is caused by happiness. Some believe it may even be caused by the sex of your baby.

While you might be happy and excited during your own pregnancy, the glow actually has numerous possible medical causes. These are primarily related to fluctuations in hormones and blood flow, but the glow can also be attributed to other changes you’re going through.

Hormone fluctuations

The increased amounts of hormones released during pregnancy can make your skin look flushed, giving you the tell-tale glowing look. Such hormones include estrogen, progesterone, and human chorionic gonadotropin.

Increased blood flow

During pregnancy, your body produces more blood. This is because your uterus and vital organs need more blood to support your growing baby. Such an increase in blood volume also dilates your blood vessels, making your skin look flushed.

Increased oil in your skin

Some women experience more oil production from their sebum glands, thanks to hormone fluctuations. Also, more blood volume can increase the secretion of oil. You may be especially prone if you already have oily or combination skin.

This can have some unwanted side effects, such as acne. But along with acne, increased oils can also make your face look like it’s glowing.

Skin stretching

Combined with increased blood flow and hormonal changes, skin stretching can also make your skin glow during pregnancy.

Heat rashes

It’s not uncommon to feel hotter than normal during pregnancy. Not only are you dealing with hormones but the extra weight you’re carrying to support your baby can also increase your body temperature. This can cause heat rashes or hot flashes, both of which can create a “glowing” effect on your skin.

Worsening of preexisting skin conditions

If you have certain preexisting skin conditions, your symptoms may be worse during pregnancy. Such conditions include eczema, rosacea, and psoriasis. Due to increased blood flow and hormones, affected skin may redden further and look more noticeable. Sometimes this is mistaken for signs of pregnancy glow.

There’s no set timeframe for experiencing pregnancy glow. However, you may be more likely to experience this glow during the height of changes in your body, especially during the second trimester.

The glow of pregnancy — as well as its underlying causes — go away soon after you give birth. This isn’t a permanent change to your skin.

While every woman experiences hormone fluctuations naturally from pregnancy, this doesn’t mean everyone will experience pregnancy glow. If you don’t, it doesn’t mean there’s anything wrong. Instead, this could indicate that your skin reacts differently to what’s going on with the rest of your body.

Other skin effects you might experience instead

As already mentioned, pregnancy acne occurs when your oil glands produce more sebum than normal. Not only can it make your skin look shiny, but it can lead to blemishes, too.

You should continue washing your face twice a day per usual, but you may need to switch to oily skin products for the duration of your pregnancy. Talk with your doctor about safe products for use during pregnancy.

“Pregnancy mask” is another pregnancy-related skin condition that may affect some women and not others. This condition refers to brown spots on your skin caused by hyperpigmentation from increased melanin production in your skin. These blotches go away after pregnancy when your hormone levels drop, but sun exposure can make them worse. Wear a sunscreen every day to help prevent this.

While you’re waiting to learn your baby’s sex, it can be fun to guess. You’ve likely heard that certain food cravings or aversions can reveal whether you’re having a boy or a girl, as well as the way you “carry” your baby throughout pregnancy.

Some people also say that pregnancy glow can indicate whether you’re having a boy or a girl. However, there’s no scientific evidence that backs up these claims. Anecdotal evidence online reveals a combination of people who state correlations of pregnancy glow between both girls and boys.

If you really want to know your baby’s gender before birth, it’s best to wait until the 16-week mark when your doctor may be able to tell on an ultrasound. You may happen to have a pregnancy glow at this point too, but it’s unlikely there’s any connection.

Pregnancy glow is just one of the many changes you might experience during pregnancy. Other changes can include stronger nails, thicker hair, and reduced dry skin. There are many reasons these things happen, so it’s safe to say pregnancy glow isn’t a myth — though you shouldn’t be concerned if you don’t have it.

Always talk to your doctor if you have concerns about any changes going on in your body during pregnancy.