These chemicals interact with hormone systems, influencing synthesis, regulation, transport, metabolism, and hormone reception, which are all especially vulnerable during pregnancy.
The new study published in Environmental Research, examined the association between personal care product use and the levels of sex steroid hormones, including estrogens and progesterone and thyroid hormones among pregnant women.
They also explored how demographic factors impact the use of certain personal care products.
Researchers collected blood samples from 1,070 pregnant women between 18 and 40 years of age to examine environmental exposures in pregnant women and their children who live in the northern karst zone of Puerto Rico.
Participants underwent physical exams and completed a series of questionnaires providing their demographics, occupation, lifestyle, and use of personal care products.
Participants also provided blood samples twice throughout their pregnancies, which were analyzed for nine sex steroid and thyroid hormones.
Researchers found that the use of hair products, particularly hair dyes, bleach, relaxers, and mousse are associated with lower levels of sex steroid hormones, which have a critical role in maintaining pregnancy and fetal development.
Disruptions of these hormones may contribute to adverse maternal and pregnancy outcomes like growth restriction, preterm birth, and low birth weight.
They also found that socioeconomic variables, such as income, education, and employment status, influence the use of personal care products among pregnant women in Puerto Rico. Additionally, employed participants reported using more cosmetics than those who were unemployed.
This data is important because it will allow us to identify populations who are at an increased risk of chemical exposures associated with personal care product use.
Researchers recommend that primary physicians and obstetricians should speak to reproductive-age women about the potential health impact of endocrine-disrupting chemicals, like those found in hair products.