Kiehl's Powerful-Strength Vitamin C Serum

Glycerin is a widely used humectant that supports hydration and the skin barrier, with a long safety record and no known pregnancy or breastfeeding concerns in topical cosmetic use.

Vitamin C antioxidant used to support brightness and photoprotection; functions as an antioxidant/pH adjuster in cosmetic formulas. No pregnancy-specific contraindications are identified for topical cosmetic use.

A silicone polyether used mainly as an emulsifier and conditioning ingredient. The Cosmetic Ingredient Review concluded that this ingredient is safe in current cosmetic use. Concentrated-material tests found limited transient irritation, while a finished cosmetic containing 15% was non-irritating in human patch testing; no pregnancy- or breastfeeding-specific concern is identified for normal topical use.

A stable vitamin C derivative used as an antioxidant and skin-conditioning ingredient. The Cosmetic Ingredient Review concluded that ascorbyl glucoside is safe in current cosmetic use; normal topical exposure does not identify a pregnancy- or breastfeeding-specific concern.

Amino-acid-derived conditioning and slip ingredient used especially in powders and colour cosmetics. Reviewed cosmetic safety sources support normal topical use, with no pregnancy- or breastfeeding-specific topical signal identified in the material reviewed.

An inert inorganic powder used to improve slip, texture and soft focus in makeup. Cosmetic safety reviewers concluded that cosmetic-grade boron nitride is safe in current cosmetic use. No pregnancy-specific concern is identified for normal skin application; as with cosmetic powders generally, avoid deliberately inhaling airborne powder or airbrush spray.

Skin-conditioning ingredient commonly used in leave-on skincare. Reviewed cosmetic safety sources support normal topical use, with no pregnancy- or breastfeeding-specific topical signal identified in the material reviewed.

Humectant and skin-conditioning ingredient in the hyaluronate family. Reviewed cosmetic safety sources support current cosmetic use, with no pregnancy- or breastfeeding-specific topical concern identified in the material reviewed.

Limonene is a common fragrance component used at low levels in cosmetics; it is not a pregnancy-specific concern in topical use, but it is a recognised fragrance allergen and may trigger irritation or sensitisation in some people, especially if the product oxidises over time.

A lemon-scented mixture of the aldehydes geranial and neral used in fragrance. Citral is a recognised skin sensitiser, but current cosmetic concerns relate to allergy and concentration rather than a pregnancy-specific hazard from normal topical use.