Melasma or chloasma (the "mask of pregnancy") is common among pregnant women, and looks like dark patches on the forehead, cheeks, or upper lip. Pigmentation levels, sent soaring by your changing hormones, are to blame for this discoloration. It should fade after delivery, but there are a few things you can do to protect your skin and avoid getting it in the first place. Minimize sun exposure, especially to your face. Always apply a broad spectrum, high UB protection sunscreen with an SPF of at least 30, and always cover up when you're in the sun. Use mild soaps and cleansers that are oil- and fragrance-free. These are less likely to contain chemicals that react negatively with the sun. If your mask hasn't faded by a few months after delivery, talk to your doctor. She'll be able to recommend bleaching creams and other treatments.