Eyebrow lightening typically involves oxidizing agents and alkalizing chemicals. Systemic absorption is generally low, but the eye area is delicate, so irritation and allergic dermatitis are key concerns—especially in pregnancy. A conservative approach is to postpone chemical lightening in the first trimester; later, keep contact time short, ensure good ventilation, and avoid spreading onto surrounding skin. Non-chemical alternatives (lighter brow gels/mascara) reduce exposure.