Methodology
The same dataset behind the app powers each product result: hazard, mechanism, exposure, source quality, and pregnancy-specific context.
Severity 0.00-0.18
No pregnancy-specific concerns at typical cosmetic concentrations and routes of use, based on current evidence.
Niacinamide
Barrier-supporting vitamin B3 with no known pregnancy-specific risk in the dataset.
Panthenol
A pro-vitamin B5 humectant marked safe across ingredient references.
Severity 0.18-0.38
Minor cautions such as irritation potential, limited pregnancy data, or less transparent fragrance blends.
Azelaic Acid
Often used for blemishes and pigmentation; recorded as low risk with concentration context.
Lactic Acid
A gentle AHA at modest cosmetic strengths, with irritation as the main caution.
Severity 0.38-0.68
Ingredients we recommend avoiding or discussing first because of systemic, endocrine, or data-gap concerns.
BHT
Tracked as medium risk because of systemic and endocrine concern signals.
Oxybenzone
A sunscreen filter flagged for endocrine disruption concerns in the evidence set.
Severity 0.68-1.00
High-concern categories where strong warnings, contraindications, or systemic exposure drive the score.
Tretinoin
A retinoid category ingredient with strong pregnancy warnings in the dataset.
Isotretinoin
Systemic retinoid with well-known pregnancy contraindication warnings.
Band-first logic means the riskiest ingredient sets the product band, so one avoid-level ingredient cannot hide behind safer ones. Each example is tied to the medical and regulatory evidence base detailed below.
Scoring flow
Every product follows the same four-part process. The result keeps the underlying evidence visible instead of reducing a formula to an unexplained number.
We normalise each INCI list so product formulas line up with the ingredient library, including synonyms and dosage hints.
Matched ingredients carry hazard, mechanism, exposure, evidence, and source notes.
The riskiest ingredient sets the product band so one avoid-level ingredient cannot hide behind safer ones.
Severity is translated into the 0-100 MamaSkin Safety Score shown with ingredient explanations.
Clinical guardrails
Ingredient detail screens explain terms like teratogenic, contraindicated, endocrine disruptor, and fetotoxic in plain language.
Evidence base
Public medical, regulatory, and systematic-review sources are combined with product ingredient data and reviewed into plain-language flags.
Detailed methodology
A MamaSkin result is not a simple count of good and bad ingredients. It combines ingredient identity, evidence quality, pregnancy relevance, expected exposure, and uncertainty. The risk band communicates the main safety conclusion. The number adds useful detail within that conclusion.
Direct pregnancy evidence is uncommon for many cosmetic ingredients. The review therefore separates strong, direct evidence from indirect or preliminary signals instead of presenting every study as equally conclusive.
An explicit contraindication can determine a high-risk band even when the rest of a formula is low concern. In contrast, a theoretical mechanism with little evidence of topical exposure is recorded with more uncertainty and does not automatically carry the same weight.
Official medicine labels, clinical guidance, and regulator warnings carry particular weight when they identify a pregnancy-specific restriction or a well-established harmful ingredient class.
Pregnancy outcome data, pharmacovigilance reports, clinical literature, and systematic reviews are considered when they are relevant to the ingredient, route of exposure, and intended cosmetic use.
Published opinions from medicine regulators and cosmetic safety bodies help establish recognised hazards, permitted uses, concentration limits, and areas where evidence remains incomplete.
When direct pregnancy data are limited, the review also considers biological mechanism, systemic exposure, metabolites, animal findings, and evidence from closely related ingredients. These signals are interpreted with their uncertainty visible.
A published hazard does not describe exposure by itself. The assessment asks how closely the evidence matches ordinary cosmetic use and clearly flags the information that is missing.
The band is the primary conclusion. It reflects the highest-concern ingredient that is relevant to the formula, so a retinoid warning cannot be averaged away by water, glycerin, or other low-concern ingredients. This is why two products with many similar ingredients can still sit in different bands.
Within each band, the 0-100 score helps distinguish stronger evidence, more relevant exposure, and greater uncertainty. The ingredient explanations remain essential because the same number can arise from different evidence patterns.
A catalogue score cannot account for allergies, broken skin, prescribed treatment plans, exact application amounts, occupational exposure, or an individual medical history. It also cannot guarantee that a retailer or brand has published the latest formula.
MamaSkin provides pregnancy-focused information, not a diagnosis or a replacement for a midwife, GP, obstetric team, pharmacist, or dermatologist. Personal clinical advice should take priority when circumstances differ from typical cosmetic use.
Safety information is versioned by the available evidence and product formula. A changed result does not necessarily mean an earlier assessment was careless. It may reflect a reformulation, a corrected ingredient match, or stronger new evidence.
New clinical literature, systematic reviews, safety opinions, or regulator guidance can change the evidence record for an ingredient.
Brands reformulate products. A current INCI list may produce a different result from an older version sold under the same product name.
Synonyms, spelling variants, derivative names, and incomplete retailer data are normalised so the intended ingredient record is used.
A disclosed concentration, clearer product directions, or more relevant topical-use evidence can support a more specific assessment.
Source links show where different parts of the evidence record can be checked. They do not imply that every organisation has reviewed or endorsed MamaSkin, and no single database answers every cosmetic pregnancy-safety question.