Olaplex has not been tested in clinical trials on pregnant women, so there’s no definitive “yes” or “no” from regulatory bodies. However, the product’s active ingredient has very limited ability to penetrate skin and enter the bloodstream, which makes the theoretical risk to a developing baby extremely low. Here’s what we actually know about the chemistry and the one ingredient that did raise legitimate concerns.
How the Active Ingredient Works on Hair
Every Olaplex product is built around a single patented molecule called Bis-Aminopropyl Diglycol Dimaleate. It works by reattaching broken disulfide bonds inside the hair shaft, which is why it repairs damage from coloring, bleaching, and heat styling. The molecule is designed to bond with hair protein, not to be absorbed through skin into your body.
Australia’s Industrial Chemicals Introduction Scheme (AICIS) evaluated this ingredient and found it “likely to have limited dermal absorption” based on its chemical properties. In plain terms, the molecule doesn’t dissolve easily into skin because of its structure. When researchers look at how well a chemical crosses the skin barrier, they measure something called its partition coefficient. This ingredient’s score is very low (between -2.8 and -2.4), meaning it strongly prefers to stay in water rather than pass through the fatty layers of your skin. That’s a good sign for pregnancy safety, because a chemical that can’t get through your skin can’t reach your bloodstream or your baby.
The AICIS evaluation did note that the ingredient “may have potential for systemic toxicity at high concentrations following repeated oral exposure,” meaning if someone swallowed large amounts repeatedly. But the agency concluded that toxic effects “are not expected under the proposed use” as a hair care product, given how little gets absorbed through skin and how briefly it contacts your scalp compared to something like a body lotion you wear all day.
The Lilial Controversy
The real pregnancy concern around Olaplex wasn’t its active ingredient. It was a fragrance component called lilial (also listed as butylphenyl methylpropional on ingredient labels). Lilial was flagged by European regulators because animal studies linked it to reproductive harm, including potential effects on fertility and fetal development. The EU announced a phaseout in September 2020, with a final deadline of March 2022.
Olaplex previously used lilial in small amounts as a fragrance in two products: No. 3 Hair Perfector and No. 2 Bond Perfector. After the EU announcement, the company removed lilial from both products globally, not just in European markets. Olaplex now states clearly that it “does not currently manufacture or sell products containing lilial.”
This matters if you’re pregnant because old stock could theoretically still exist on some shelves. If you have a bottle of No. 3 or No. 2 purchased before mid-2022, check the ingredient list for butylphenyl methylpropional. Any bottle manufactured after the reformulation won’t contain it. Current products sold through authorized retailers are lilial-free.
Other Ingredients to Check
Olaplex products are free of parabens, phthalates, and sulfates, which are the three categories that raise the most common pregnancy flags in personal care products. The product line is also vegan and cruelty-free, though neither of those labels directly relates to pregnancy safety.
That said, the Olaplex line includes more than a dozen different products, and each has its own formula beyond the shared active ingredient. Shampoos, conditioners, styling creams, and oils all contain different supporting ingredients like silicones, plant extracts, and preservatives. If you have specific sensitivities or want to screen every ingredient, apps like EWG’s Skin Deep or Yuka let you scan barcodes and flag individual components.
Salon Treatments vs. At-Home Products
There’s a meaningful distinction between using Olaplex at home and getting it applied during a salon color service. The Olaplex system used in salons (No. 1 Bond Multiplier and No. 2 Bond Perfector) is mixed directly into bleach or color formulas. In that context, the bigger question isn’t really about Olaplex itself. It’s about the hair dye or bleach it’s mixed with. Most major medical organizations consider occasional hair coloring during pregnancy to be low-risk, especially after the first trimester, because the chemicals in modern dyes also have limited skin absorption. But the exposure is different from simply applying a treatment like No. 3 at home for 10 minutes.
At-home products like No. 3 Hair Perfector, No. 4 Shampoo, or No. 5 Conditioner involve brief scalp contact and rinse off quickly. The amount of any ingredient that could theoretically cross the skin in that window is negligible. Leave-in products like No. 6 Bond Smoother or No. 7 Bonding Oil sit on hair longer but are applied mainly to the hair shaft, not the scalp, further reducing any absorption.
What the Evidence Adds Up To
No regulatory agency has flagged current Olaplex formulas as unsafe for pregnant users. The active ingredient has poor skin penetration, the problematic fragrance ingredient has been removed globally, and the product line avoids the most commonly flagged preservatives and additives. The absence of direct pregnancy studies means no one can guarantee absolute safety, which is true for the vast majority of cosmetic products on the market. But based on the chemical profile and how these products are used, the risk profile is reassuringly low.