Which shampoo should be used when one is pregnant?

It is often said that hair becomes less greasy during pregnancy. While this may be true for some women, this does not exempt the use of shampoo. Shampoo helps to cleanse the scalp and remove all accumulated dust, pollution, and sebum particles, more effectively than a simple water rinse could. Moreover, some shampoos are enriched with active ingredients specifically targeting certain hair issues, such as dry, dull, or quickly greasing hair.

During pregnancy, some women also notice changes in the texture and thickness of their hair. This transformation is due to the increase in estrogen levels in the bodies of pregnant women. This steroid hormone acts on the anagen phase of follicular growth, that is, the hair growth phase. During this phase, cells divide rapidly. By attaching to a specific receptor, estrogens stimulate this growth. To respond to these changes, it may be relevant to adapt one's shampoo.

During pregnancy, the choice of cosmetic products one uses is not insignificant. Just as with diet, it is necessary to choose products that are suitable for pregnant women and pose no danger to them or their babies. Regarding shampoos, the risks are very limited, given the short contact time with the scalp. Indeed, after lathering, shampoos are immediately rinsed off and are not treatments intended to remain on the skin.

Thus, we advise you to select your shampoo based on the nature of your hair. If your hair tends to get oily quickly, consider using purifying shampoos with green clay or peppermint. If it's dry, opt for hydrating and nourishing shampoos, like those with shea butter or vegetable oil (coconut, avocado...). Finally, if you have curly or kinky hair, you should also choose a shampoo that contains nourishing ingredients, such as macadamia nut oil or argan oil.

Even though shampoos are among the cosmetic products posing the least risk to pregnant women, it is important to note that some active ingredients they may contain are not recommended. This is particularly the case for essential oils, sulfates, parabens, titanium dioxide nanoparticles and phthalates.

Indeed, certain essential oils are neurotoxic and can cause spasms or nausea. Moreover, they are said to be mutagenic and teratogenic, meaning they could increase the risk of malformations in the embryo and potentially cause mutations in DNA. However, there are not enough scientific studies to make a definitive conclusion. The other ingredients mentioned above should be avoided, as they are suspected to be endocrine disruptors. Nevertheless, studies on this subject contradict each other, and these ingredients are contraindicated during pregnancy only as a precautionary principle.

• EINARSON A. & al. Safety of skin care products during pregnancy. Canadian Family Physician (2011).