Lactic acid, an Alpha Hydroxy Acid (AHA), is a gentle chemical exfoliant frequently used in skincare for its dual benefits of mild cell turnover and hydration. As a humectant, it draws moisture into the skin, helping to restore a plump and dewy appearance while also dissolving the bonds between dead skin cells. Many individuals re-evaluate their beauty routine upon becoming pregnant, focusing on ingredient safety. This article addresses the specific safety profile of lactic acid and its context for use during this time.
The Safety Profile of Lactic Acid During Pregnancy
Lactic acid is generally considered a low-risk skincare ingredient for use during pregnancy by dermatologists and medical professionals. This consensus is based on the nature of the molecule and the minimal amount that enters the bloodstream after topical application.
The key factor supporting its safety is its large molecular size, which significantly limits its ability to penetrate the skin barrier and achieve systemic absorption. The Cosmetic Ingredient Review (CIR) expert panel concluded that lactic acid is safe for use in cosmetic products at concentrations up to 10%, provided sun protection is used.
To maintain safety, it is prudent to stick to lower, over-the-counter concentrations. Some professionals specifically suggest concentrations of 5% or lower. High-concentration, professional-grade lactic acid peels should be avoided, as these treatments are designed for deeper penetration and carry a higher theoretical risk of systemic exposure.
Why Skincare Absorption Matters
The safety concern surrounding any topical product during pregnancy centers on the potential for systemic absorption, which is the process of an ingredient moving from the skin surface into the bloodstream. Once in the maternal bloodstream, a substance has the potential to cross the placental barrier and affect the fetus. The skin acts as a protective barrier, but its effectiveness can vary depending on the ingredient’s properties.
A substance’s molecular weight, concentration, and the vehicle it is formulated in all influence its absorption rate. Ingredients with a lower molecular weight, higher concentration, and those applied to a large surface area for a prolonged period are more likely to be absorbed systemically.
The evaluation of safety is therefore rooted in differentiating between a topical effect and systemic exposure. Since controlled studies on pregnant humans are ethically restricted, safety evaluations rely on molecular size data, animal studies, and the established safety of long-term clinical use. This scientific context explains why certain molecules are deemed safe while others are strictly prohibited.
How Lactic Acid Compares to Other Skincare Acids
Lactic acid’s favorable safety profile becomes clearer when compared to other active ingredients commonly used for exfoliation and anti-aging. Retinoids, derivatives of Vitamin A, represent the highest-risk category and must be avoided entirely during pregnancy. Oral retinoids like isotretinoin cause severe birth defects, and experts recommend avoiding topical retinoids due to their relation to the oral form.
Salicylic acid, a Beta Hydroxy Acid (BHA), also requires careful consideration, though it is often considered low-risk in small concentrations. Salicylic acid is chemically related to aspirin, an oral salicylate. High oral doses of salicylates have been associated with complications during pregnancy, leading to caution regarding topical use. Topical salicylic acid is generally considered low-risk at concentrations of 2% or less, especially when used as a quick-rinse cleanser.
Lactic acid, along with glycolic acid, is an Alpha Hydroxy Acid often preferred as an exfoliant. Lactic acid is considered a safer alternative to address concerns like acne and hyperpigmentation without the theoretical concerns associated with high-dose salicylate absorption.
Practical Tips for Acid Use and Alternatives
If choosing to incorporate lactic acid into a pregnancy skincare routine, it is wise to start slowly to monitor for adverse reactions. Skin sensitivity can increase significantly due to hormonal changes, so a patch test on a small, discreet area of skin is highly recommended before full facial application. Sticking to concentrations in the 5% to 8% range offers a balance of efficacy and safety.
AHA use increases skin photosensitivity, making daily sun protection a non-negotiable step. Pregnant individuals should apply a broad-spectrum sunscreen with an SPF of 30 or higher every morning, as AHAs can increase the risk of hyperpigmentation like melasma.
For those uncomfortable using any AHA, several effective and safe alternatives are available. Azelaic acid is a preferred option, often recommended by dermatologists for its ability to target acne, redness, and pigmentation, and is classified as Pregnancy Category B. Gentle physical exfoliants, such as soft cleansing brushes or finely milled scrubs, can also provide surface exfoliation without any risk of systemic absorption.