Your prom's a fading memory and now you get zits? If you’re breaking out in your 20s, 30s, 40s and beyond, you’re not alone. "Even if you never had acne as a teenager, you may experience it for the first time as an adult,” says Arielle Kauvar, M.D., director of New York Laser & Skin Care in New York City. “Some women even develop acne after menopause.”

Adult acne is the most common skin disorder in the U.S., affecting 40 to 50 million Americans. It tends to run in families. Pimples are clogged pores caused by an overproduction of oil, which stimulates the growth of bacteria called P. acnes. Many breakouts in adult women are a result of hormone fluctuations, which is why acne may flare during menstruation, pregnancy, perimenopause and menopause. “Other factors are skin-clogging cosmetics and stress—it increases the male hormone androgen which boosts oil production,” says Dr. Kauvar.

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