During pregnancy, some women experience fuller hair due to the extra boost in hormones. We take a closer look at whether or not it’s safe to color your hair while pregnant, why hair loss is common after pregnancy and what you can do to treat your hair.
Hormonal fluctuations can bring about a number of different bodily changes during pregnancy, including some to your hair. When pregnant, many women feel that their hair looks fuller, thicker and shinier. The reason? An increased presence of estrogen, which has an effect on the hair growth cycle.
What happens to hair while pregnant?
A common misconception is that you grow more hair when pregnant. This is not the case: the hair is not any thicker or more prolific than usual- rather, less of it is falling out. Estrogen, the female hormone, increases significantly during pregnancy, which has an impact on hair in general.
This means that along with the strands on your scalp, eyebrows and eyelashes may appear a little thicker than usual.
The downside is that this may result in facial and body hair also growing faster than usual, because of the presence of increased androgen (a hormone associated with male characteristics), although this is not the case for all women(1).
The average woman sheds about
100strands a day.
How does the hair cycle work and how does it change while pregnant?
Hair growth is divided into 3 stages:
● Anagen (growing stage)
● Catagen (renewal stage)
● Telogen (resting stage)
The “shedding stage” is referred to as exogen. Normally, 85-95% of the hair on the head is growing and 5-15% is in the resting stage(2). After the resting period, hair naturally falls out (caused by brushing or washing) and is replaced by new growth. The average woman sheds about 100 strands a day.
When pregnant, the average percentage of anagen hairs increases from the normal 85-95% by the second trimester. In addition, during the second and third terms, only about 10% of hairs are in telogen (the resting stage)(3). Because of the presence of estrogen, the exogen phase is delayed, and the anagen phase is prolonged, which means that there is a slow conversion of hair from growing stage to shedding stage. This reduced amount of hair shedding is the reason why hair looks and feels thicker and fuller(3).
Is dandruff common during pregnancy?
Dandruff during pregnancy is often a result of hormonal changes too. Because of this, the hair care products you use may irritate the scalp. While pregnant, the body is more sensitive to skin changes(4), therefore it may be worth updating your hair care routine to accommodate these hormonal fluctuations.
Is it safe to use color treatments on your hair when pregnant?
The science is inconclusive when it comes to color treatments. Some studies show that receiving 3-4 hair treatments won’t have an adverse effect on the baby(5), whereas others suggest it may be dangerous(6), and recommend avoiding it completely(6). To err on the side of caution, we recommend that you consult with your gynecologist or obstetrician, as it may be best to forgo hair treatments such as coloring or chemical treatments (like straightening) until after pregnancy.
What happens to hair after delivery?
Post-pregnancy, hair volume will gradually diminish. This occurs as estrogen levels decrease and hormones begin to stabilize. In normal circumstances, it won’t be any thinner than before you were pregnant, but rather will revert back the its old volume and condition. After delivery, the hair growth conversion that was so delayed during pregnancy accelerates and the transition from anagen to telogen occurs, as the hair cycles become synchronized on the scalp. This means that postpartum hair loss is common. About 30% of the hair reaches the resting stage after 9 weeks, explaining why postpartum hair loss is experienced 2 to 4 months after childbirth(3).
Although complete hair regrowth usually occurs, some women may notice that the hair is not as abundant as it was before(2). Many women suffer from telogen effluvium during postpartum(3). This refers to the process of stress affecting hair roots, and causing them to be pushed prematurely into the resting state. So if you experience chronic hair loss, it’s important to consult your dermatologist as soon as possible.
SOURCES:
1. Makieva, S. et al, 'Androgens in pregnancy: roles in parturition' in Human Reproduction Update, 20.4 (2014) pp. 542–559 [Accessible at: https://academic.oup.com/humupd/article/20/4/542/2952640]
2. Kar, S. et al, 'Pregnancy and Skin' in Journal of Obstetrics and Gynecology in India 2012 62.3 pp.268-275 [Accessible at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3444563/]
3. Piérard-Franchimont, C. et al, 'Alterations in Hair Follicle Dynamics in Women' in BioMed Research International 2013 [Accessible at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3884776/]
4. Fernandes, L.B. et al, 'Clinical study of skin changes in low and high risk pregnant women*' in Brazilian Society of Dermatology 90.6 (2015) pp. 822-826 [Accessible at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4689069/]
5. Chua-Gocheco, A. et al, 'Safety of hair products during pregnancy: Personal use and occupational exposure' in Canadian Family Physician 54.10 (2008) pp. 1386-1388 [Accessible at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2567273/]
6. Saitta, P. et al, 'Is There a True Concern Regarding the Use of Hair Dye and Malignancy Development? A Review of the Epidemiological Evidence Relating Personal Hair Dye Use to the Risk of Malignancy' in Journal of Clinical Aesthetic Dermatology 6.1 (2013) pp. 39–46 [Accessible at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3543291/]