What after-sun care is suitable for pregnant women?

During pregnancy, there is a significant increase in the levels of oestrogen and progesterone in the body. These steroid hormones stimulate the process of melanogenesis, which is the synthesis of melanin, the pigment responsible for skin coloration. Therefore, when exposed to sunlight without protection, pregnant women are prone to hyperpigmentation issues, manifesting as the appearance of the "pregnancy mask". This is why it is highly recommended for pregnant women to apply sunscreen daily on exposed areas, regardless of their phototype.

Furthermore, after a sunny day, it is recommended that pregnant women generously apply an after-sun product to the parts of their body that have been exposed. This rich and refreshing treatment helps tosoothe the skin while providing it with the hydration and lipids it needs to rebuild its hydrolipidic film and skin barrier, which are compromised by sun exposure. After-sun products also help to reduce inflammation caused by UV rays and limit vasodilation phenomena, which are common when exposed to the sun. These effects are particularly beneficial for pregnant women, who experience increased blood circulation from the fourth week of pregnancy, a period corresponding to the beginning of blood exchanges between the mother and the embryo. These exchanges cause an elevation in body temperature, which is further increased during sun exposure.

Additionally, some pregnant women may experience tightness and sensations of dryness on their skin due to the hormonal and structural changes their bodies undergo during pregnancy. As a result of weight gain, the cells in the stratum corneum are stretched, weakening their barrier function. Ceramides, which play a role in intercellular junctions, then allow more water to escape, increasing the risk of skin dehydration. This is exacerbated by UV exposure, highlighting the importance of rehydrating the skin well after sun exposure, a practice that also helps prevent stretch marks.

Pregnancy requires taking certain precautions and adapting one's habits as the skin tends to be more sensitive and reactive during this period. Therefore, it may be wise to opt for minimalist formulas, containing few active ingredients, to limit the risk of allergies and reactions. We also recommend choosing after-sun products that do not contain fragrances or alcohol derivatives, as these substances can be irritating to sensitive skin. Additionally, avoid cosmetics with ingredients suspected of being endocrine disruptors, such as parabens (propyl-paraben, butyl-paraben...), phthalates (diethyl phthalate...), BHA, BHT, triclosan...

Finally, certain ingredients that can be incorporated into after-sun products are strictly contraindicated during pregnancy. This includes essential oils, which are sometimes added to formulations for their sensory properties. Indeed, due to their ketone function, some essential oils are considered neurotoxic and can cause convulsions, spasms, and nausea. Others may have an effect on the hormonal system.

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

• TYLER K. H. Physiological skin changes during pregnancy. Journal of Clinical Gynecology and Obstetrics (2015).

• BJÖRKLUND S. & al. The Effect of UVB Irradiation and Oxidative Stress on the Skin Barrier—A New Method to Evaluate Sun Protection Factor Based on Electrical Impedance Spectroscopy. Sensors (2019).