VeriMomShould I Avoid thiourea During Pregnancy? | VeriMom
Reviewed by VeriMom Editorial Team · Last reviewed
ECHA regulatory hazard statements
- •H351
- •H361D
What to use instead
Pregnancy-safe ingredients that serve a similar function:
Pregnancy-safe products to use instead
Products built around the safer ingredients above, scored "no known risks" or "low risk".
Sources & references
Authoritative references used to score this ingredient.
Pregnancy-Safe Alternatives to thiourea | VeriMom
Ingredients — Pregnancy-Safe Ingredients Database — 28,000+ Ingredients Rated
See also
FAQ
- Is thiourea safe during pregnancy?
- Thiourea is listed with a harmonised reproductive/developmental hazard (H361d — 'suspected of damaging the unborn child') by EU sources, and experimental studies show it inhibits thyroid hormone synthesis (antithyroid action) which can cause developmental effects in animals; this provides a suspected reproductive hazard and a demonstrated mechanism (thyroid inhibition). Topical cosmetic use would likely give low but measurable systemic exposure (no dermal absorption data specific to cosmetic formulations found). ([echa.europa.eu](https://echa.europa.eu/documents/10162/8cf0cdee-7849-4008-99d7-d4cc17706614?utm_source=openai))
- Is thiourea safe while breastfeeding?
- Hazard and mechanism mirror pregnancy: harmonised H361d and demonstrated antithyroid activity in animals. There are no robust data on transfer of thiourea into human milk after topical exposure, so breastfeeding exposure is judged low but potentially measurable from systemic absorption; the developmental risk pathway (maternal hypothyroidism or direct exposure) remains plausible based on animal and mechanistic data. ([echa.europa.eu](https://echa.europa.eu/documents/10162/8cf0cdee-7849-4008-99d7-d4cc17706614?utm_source=openai))
- Is thiourea safe for baby skin?
- The same suspected developmental hazard (H361d) and demonstrated antithyroid mechanism apply. For baby (0–3 yr) skin, exposure score is increased by +1 because infant skin is more permeable and surface-area-to-body-weight higher; given measurable dermal absorption in adults is plausible, infant exposure is assessed as moderate. No infant-specific toxicokinetic or dermal absorption studies were located. ([echa.europa.eu](https://echa.europa.eu/documents/10162/8cf0cdee-7849-4008-99d7-d4cc17706614?utm_source=openai))
- How does VeriMom score thiourea?
- VeriMom scores thiourea at 20/100 (high risk) based on EU CosIng status, ECHA hazard classifications, and peer-reviewed PubMed studies. Our scoring pipeline is fully transparent.
- What are pregnancy-safe alternatives to thiourea?
- See our curated list of pregnancy-safe alternatives to thiourea based on similar function and a no-known-risks safety band.
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Medical Disclaimer
This information is for educational purposes only and does not constitute medical advice. Safety scores are based on publicly available data and may not reflect all risks. Always consult your healthcare provider before using any product during pregnancy or breastfeeding.