Endocrine disruptors & pregnancy

17/11/2022

Endocrine disruptors have been at the heart of scientific discussions for several years because they impact our hormonal system, and their sources are multiple. Focus on their effects during pregnancy ...

Exposure to these harmful substances can happen in several ways (ingestion, inhalation or skin contact), at different doses, and by many sources. There are a wide variety of endocrine disruptors, such as bisphenol A, phthalates, parabens, lead, teflon, etc. These molecules can act in different ways on the endocrine system: by mimicking a natural hormone, disrupting its transport, its degradation, or by preventing the binding of the hormone to its receptor. They can have an effect on the individual by direct contact, but also affect the fetus when this individual is a pregnant woman.

Indeed, an international consortium led by scientists from Inserm has evaluated the impact of phenols, phthalates, and parabens on pregnant women’s thyroid physiology. After analysis of blood and urine samples collected in a cohort from Grenoble, the researchers concluded that several molecules known to have a deleterious effect on thyroid function were present, and therefore that almost all the patients had been exposed to them. The thyroid gland is located in the neck and produces the triiodothyronine (T3) and thyroxine (T4) hormones, under the control of a negative feedback loop involving the pituitary thyroid stimulating hormone (TSH). These hormones are of utmost importance for the proper development of the fetus. This study showed that the concentrations and metabolism of thyroid hormones and TSH were affected.

These conclusions can make us wonder about the impact that this exposure to endocrine disruptors may have had on the children of the women included in this cohort, particularly on their growth and brain development. These substances’ harmful effects are a public health issue, and it is regularly addressed by the French National Agency for Food Safety (Anses) through various reports, national strategies, and scientific studies.