Pregnancy often brings increased skin sensitivity and a heightened risk of developing hyperpigmentation. Sun protection is particularly important to manage these changes, but it raises concerns about the ingredients in topical products. The primary issue for expectant mothers is the systemic absorption of certain chemical compounds found in many conventional sunscreens, as these small-molecule filters can pass through the skin barrier and enter the bloodstream.
Identifying Chemical UV Filters to Avoid
Many popular sunscreens utilize chemical filters designed to absorb ultraviolet radiation, but several ingredients are associated with systemic absorption. Expectant mothers should carefully check the “active ingredients” list for common compounds. The most widely studied filter is Oxybenzone (also listed as Benzophenone-3), which has shown exceptionally high absorption rates into the body after standard application.
The FDA has confirmed that six chemical UV filters are absorbed into the body at concentrations exceeding levels that warrant further safety review. These ingredients should be avoided during pregnancy:
- Oxybenzone (Benzophenone-3)
- Octinoxate (Ethylhexyl Methoxycinnamate)
- Homosalate
- Octisalate
- Avobenzone
- Octocrylene
Systemic Absorption and Hormonal Concerns
The concern surrounding these chemical UV filters stems from their ability to be absorbed into the body. Studies have shown that following regular use, these compounds can be detected in blood plasma, breast milk, urine, and amniotic fluid. This widespread distribution indicates that the chemicals can cross the placental barrier, raising questions about potential exposure to the developing fetus.
These chemical UV filters are classified as endocrine-active chemicals due to their potential to disrupt the body’s natural hormonal functions. Endocrine disruption occurs when a foreign compound mimics or interferes with the natural hormones that regulate growth and development. Specifically, some filters have been linked to altered thyroid hormones in pregnant women, which are necessary for normal fetal brain development. The potential for interference with these sensitive biological pathways suggests a need for precaution during gestation.
Selecting Safe Mineral Sunscreen Alternatives
To minimize the risk of systemic absorption, the recommended alternative is to use physical or mineral sunscreens. These products use active ingredients that sit on the surface of the skin, forming a physical barrier to block ultraviolet rays. The two primary active ingredients are Zinc Oxide and Titanium Dioxide, which are the only two UV filters currently classified by the FDA as Generally Recognized as Safe and Effective (GRASE).
Zinc Oxide and Titanium Dioxide work by scattering and absorbing UV radiation on the skin’s surface. When selecting a mineral formula, look for “broad-spectrum” coverage to ensure protection against both UVA and UVB rays. It is also advisable to choose lotions or creams over spray formulations, as this avoids the potential for inhaling the mineral particles, which can pose a risk to the respiratory system. Reapplying the sunscreen every two hours, or immediately after swimming or sweating, remains the standard for maintaining effective sun protection.