Pregnancy Hormones Cause Specific Changes in Black Hair—Here’s How and Why

Growing a tiny human causes significant changes in the body. From sensory changes such as taste and smell to hormonal changes that cause mood swings and nausea, transformative things are constantly happening–even your hair goes through a transition of its own.

Doctorate-prepared board-certified nurse midwife Dr. Chanelle Nsangou Njoya says that it’s common for many pregnant people to experience changes in their hair during pregnancy. “These changes include increased thickness and growth, as well as changes in texture and shininess.”

This change is mainly due to extraordinarily high levels of estrogen, progesterone, prolactin, and growth factors during pregnancy. “Estrogen prolongs the growing phase, which means there is less hair being shed. Hair growth isn’t just limited to the scalp—some women may also experience hair growth in less exciting places such as the face, chest, belly, and arms,” says Dr. Njoya.

While estrogen is the dominant hormone impacting hair in pregnancy, progesterone is a very close runner-up, according to Dr. Njoya. “Progesterone can act as a vasodilator contributing to increased blood flow, therefore, improving the hair's nutrition and support.” This increased blood circulation can cause fuller hair growth. 

For Black birthing people, in particular, the change of texture in their hair caused by pregnancy hormones can be a surprise. Some pregnant people report their 4a hair changing to 3b, with looser curls. Other pregnant people report having a hard time keeping moisture locked in. This means that during pregnancy, Black parents-to-be sometimes have to relearn how to manage their hair and adjust to a changing curl pattern. It’s not uncommon to have to try new products to find a new hair maintenance regimen that works.

On the other hand, some pregnant people report negative changes such as dryness, thinning, or breakage. “This is likely due to a decrease in estrogen that can happen when the oral contraceptive pill is discontinued or due to hormone imbalance,” says Dr. Njoya.

In reality, each Black woman's experience is individual and may differ during pregnancy. “It is important to remember that though hormonal changes are a key player, individual lifestyle habits like water intake, proper diet and nutrition, and underlying health conditions, also play a role,” she emphasizes.

The actual process of giving birth can itself be traumatic and trigger hair loss—the stress inflicted on the body during this time is immense, especially when medical interventions such as surgery are involved. Once the baby and placenta are delivered, a lot of the estrogen that was present to help the baby develop starts to reduce rapidly.

Dr. Njoya explains that as hormones return to pre-pregnancy levels during the postpartum period, it can possibly lead to further changes. “Some Black women will experience postpartum hair loss when the hair follicles have completed their "resting" phase and start to shed. This is called postpartum telogen effluvium.”

“Because the hair follicles have been stagnant in the growing phase it will appear that there is extreme hair loss because it's much more than the standard 100 hairs a person expectedly loses per day. This "shedding" can be expected to start roughly about three months after birth,” she says.

The good news is, these changes are unlikely to be permanent. Dr. Njoya explains that “on average, hair should return to pre-pregnancy levels with a normal growth pattern up to 12 months after the completion of breastfeeding.” She caveats this by saying that if hair loss or other negative changes to the hair continue for longer than expected, “it is important for the woman to consult with her health care provider to ensure there are no underlying health conditions.” 

Although hair changes during pregnancy are natural, there are things pregnant people can do to maintain healthy hair during this period and thereafter. “A balanced and nutritious diet should include plenty of vitamins, minerals, and protein like iron, fatty acids, and Vitamin D,” stresses Dr. Njoya. “Iron and Vitamin D deficiencies are more common in Black women. Iron deficiency is a well-known cause of hair loss and vitamin D contributes to hair follicle cycling.” These deficiencies can also change hair texture causing it to be more dull, dry, and brittle.

She recommends eating foods such as leafy greens, whole grains, salmon, avocado, eggs, nuts, and berries to stimulate hair growth. Additionally, she advises that drinking plenty of water and staying hydrated is key to keeping hair healthy before, during, and after pregnancy.

Dr. Njoya mentions that there are also certain foods pregnant people should try to avoid to protect the health of their hair. These include “high-fat and high-sugar foods which may cause hormonal imbalances which can lead to hair loss.”

It’s important to also be cautious of certain products and chemicals during pregnancy. Dr. Njoya suggests avoiding or limiting the use of “hair products containing phthalates, parabens, sodium lauryl sulfate, formaldehyde, triclosan, propylene glycol, or anything that can overload the hair.”

It’s also best to avoid chemicals like dye, highlight, or relaxers because very few studies have examined the effects of these chemicals on hair in pregnancy. “There is also a chance that these chemicals may be absorbed through the scalp and passed along to the baby,” says Dr. Njoya. If the pregnant woman can’t go without any of these chemicals, she says it’s best to “at least avoid using them in the first trimester when the baby's major organs and body systems are developing.”

Chemical hair relaxers in particular are extremely popular among Black women due to societal pressures that demonize kinky textured hair while glorifying straight silky hair. A 2022 study revealed that women who use these hair relaxers have an increased risk of developing uterine cancer–the most common cancer of the female reproductive system. They can also lead to serious hormonal issues.

Worryingly, a 2018 study discovered that when hair relaxing products were lab tested, almost 85% of detected chemicals were undisclosed on the product label. This could mean Black women are inadvertently putting their health at risk. For those who are pregnant, this could cause unknown issues for them and their baby.

Regardless of how hair changes during pregnancy, Dr. Njoya again stresses that “every woman and every "body" is different and reacts differently. So most importantly it's about balance whether that be hormones or healthy lifestyle/diet.”