You may have heard that hair becomes thick and lustrous during pregnancy. This may be true for some women, thanks to high levels of the hormone estrogen, which slows hair shedding.

Other moms-to-be, however, experience thinning hair or hair loss either during pregnancy or in the months immediately following birth.

While concerning, hair loss is normal and can be caused by things like hormones, stress on the body, or medical conditions that accompany pregnancy.

Both men and women lose an average of around 50 to 100 hairs each day. During pregnancy, rising estrogen levels slow down the natural cycle of hair follicle shedding. As a result, some women may actually lose fewer hairs while pregnant. But that’s not always the case.

Hormonal shift

Some women may experience hair thinning and shedding due to stress or shock. This condition is called telogen effluvium, and it affects a small number of women during pregnancy.

The first trimester may stress the body as the balance of hormones shifts dramatically to support the growing baby. Stress may put more of the hairs on your head, 30 percent or more, into the telogen or “resting” phase of the hair life cycle. So, instead of losing the average 100 hairs a day, you may lose 300 hairs a day.

Hair loss due to hormonal shifts may not happen right away. Instead, it may take two to four months to notice thinning. This condition doesn’t generally last longer than six months and doesn’t result in permanent hair loss.

Health issues

Likewise, health issues may arise during pregnancy, leading to telogen effluvium. The shedding can be quite dramatic, especially if it’s related to an ongoing imbalance in hormones or essential vitamins.

Thyroid problems

Thyroid disorders, like hyperthyroidism (too much thyroid hormone) or hypothyroidism (too little thyroid hormone), may be difficult to spot during pregnancy.

Of the two conditions, hypothyroidism is more common, affecting some 2 or 3 out of 100 pregnant women. Hair loss is one symptom, along with muscle cramps, constipation, and exhaustion. Around 1 in 20 women may also experience thyroid issues (postpartum thyroiditis) after baby is born. In all cases, thyroid issues are typically diagnosed with a blood test.

Iron deficiency

Iron deficiency happens when you don’t have enough red blood cells to get oxygen to different tissues in the body. It can cause hair thinning along with other symptoms, like fatigue, irregular heartbeat, exertional shortness of breath, and headache.

Pregnant women are at a heightened risk of developing iron deficiency anemia, especially if their pregnancies are spaced close together, they’re pregnant with multiples, or they have severe morning sickness. This condition can also be diagnosed with a blood test.

While hair loss with these conditions isn’t permanent, your hair may not return to its normal thickness until hormone or vitamin levels have returned to normal ranges.

Postpartum hair loss

Many women see hair loss within a few months of delivery, generally peaking around four months postpartum. This is not true hair loss, but rather “excessive hair shedding” caused by a drop in the hormone estrogen.

Again, this type of hair loss is considered telogen effluvium. While it may be quite jarring to see 300 or more hairs shedding each day, it usually resolves on its own without treatment.

Other causes

It’s important to note that hair loss with telogen effluvium is typically uniform thinning. If you notice patches or more dramatic balding, there may be other issues at play. There are also genetic and autoimmune conditions that cause hair loss, whether you’re pregnant or not.

  • Androgenic alopecia (female pattern baldness) is caused by a shortened growth phase of hair follicles and a lengthened time between shedding hair and new growth.
  • Alopecia areata causes patchy hair loss on the scalp and other parts of the body. You may experience hair loss and regrowth that is unpredictable or cyclical. There is no cure for this type of hair loss, but certain treatments may help stop loss and regrow hair.

It’s possible to be pregnant and have one of these conditions at the same time.

Trauma

Your hair loss may have nothing to do with pregnancy or genetic conditions at all. If you’ve recently had your hair in tight hairstyles, had certain beauty treatments, or treated your hair roughly, you may have what’s called traction alopecia.

Inflammation of hair follicles can lead to hair shedding and loss. In some cases, your follicles may scar, leading to permanent hair loss.

Hair loss during and after pregnancy may require no special treatment. It generally resolves on its own over time.

Doctors sometimes prescribe minoxidil (Rogaine) if hair growth doesn’t return to previous levels, but this drug is not considered safe for use during pregnancy.

In the case of conditions like hypothyroidism or iron deficiency anemia, working with your doctor to find medication or vitamin supplements that will return your levels to normal should help start the regrowth cycle with time.

The majority of treatments for other conditions, like androgenic alopecia, are also not recommended during pregnancy. Your doctor may suggest to try low-level laser treatment (LLLT), which uses red light waves to stimulate hair growth, instead of medications.

What about after giving birth?

Some medications are safe while nursing and others are not. Rogaine, for example, is not considered safe if you’re breastfeeding. It’s something you might start once you’re done nursing.

Your best resource is your doctor to help you weigh the pros and cons of different treatment options.

You may or may not be able to do anything to prevent hair loss or shedding during pregnancy. It all depends on the cause of your hair loss.

Try:

  • Eating a healthy, balanced diet. Focus on getting enough protein, iron, and other important nutrients. You may also ask your doctor about the best prenatal vitamin for you, whether over-the-counter or by prescription.
  • Asking your doctor if any medications or supplements you’re taking may contribute to hair loss.
  • Skipping tight braids, buns, ponytails, and other hairstyles that may pull at your hair. While you’re at it, resist twisting, pulling, or rubbing your hair.
  • Washing hair gently and use a wide-toothed comb to avoid pulling hair too hard while detangling.
  • Letting hair rest without harsh treatments like using hot rollers, curling irons, or hot oil and permanent treatments.
  • Speaking with your doctor. Sometimes the root of your hair loss cannot be easily determined with a physical exam. While most cases of hair loss during pregnancy are temporary, there are other situations that may require treatment for either boosting vitamin levels or regulating hormone levels.

If you’ve already lost hair, consider trying volumizing shampoos and conditioners. Heavy formulas may weigh hair down. And when conditioning, focus on the ends of your hair instead of the scalp for more lift.

There are also certain haircut styles, like a short bob, that may help your hair look fuller while it grows back.

Hair loss during pregnancy — while not especially common — is normal, especially when related to hormone changes or certain health conditions. Hair growth should resume with time or with treatment for the underlying cause.

Hair shedding after pregnancy peaks around four months postpartum. The good news is that you’re likely to regain your normal growth within six to nine months — by your little one’s first birthday.

If your hair loss continues or you notice other symptoms, consider contacting your doctor to see if there’s another possible cause for hair loss, like alopecia areata or androgenic alopecia.