Traditionally popped to prevent pregnancy, birth control pills today are prescribed for multiple other reasons to make women’s lives easier—like ridding them away from a lifetime of recurring bursts of acne that go beyond puberty. How did something made specifically to inhibit ovulation become a magic pill for women with chronic skin issues? How do birth control pills actually affect your skin?

The hormonal spiral

To understand how oral contraceptives work, we need to understand a woman’s hormonal system. “A woman’s hormonal system, responsible for her periods, works like clockwork,” says Dr. Ameya Kanakiya, consultant obstetrician and gynaecologist, menopause specialist, and co-founder of Elda Health. The pituitary gland in the brain secretes a hormone that signals the ovaries to start developing eggs. These eggs then secrete the female hormone oestrogen, which prepares the uterine bed or lining for a prospective pregnancy. “One of these developing eggs then ovulates, and the ovary now secretes the hormone progesterone, which strengthens this uterine bed,” explains Dr. Kanakiya. When you’re not pregnant, the hormone levels fall, and the uterine lining is shed, a.k.a you get your periods, and a new cycle restarts all over again.

Our hormone system plays a major part in our skin health. You’ll notice your skin glowing around the time of ovulation, thanks to oestrogen. And those pre-period breakouts—those are an effect of declining hormones.

Essentially, when you pop a birth control pill, you are consuming hormones to halt ovulation. “A birth control pill contains both the hormones oestrogen and progesterone,” says Dr. Kanakiya. So when you have a continuous supply of these hormones, the signals to develop eggs from the brain to the ovaries stop, thus inhibiting ovulation and controlling birth.

Then there are the male hormones, or androgens, which women have small amounts of in their blood, and sometimes exceed their limit. “Acne, hirsutism (increased male pattern hair growth) occurs due to an excess of these male hormones over the female ones,” says Dr. Kanakiya,

“birth control pills help to decrease the levels of these free androgens and thus help to control skin outbreaks of acne and decrease facial hair growth.” And because they affect our body’s hormone levels—maintaining a steady dose of glow-giving hormones and keeping the male hormone in check in our body—birth control pills help control hormone-related skin issues like acne and keep the skin looking healthy. “While there are different ways of treating acne like prescribing antibiotics and skin ointments which control the over-production of oil and sebum on the skin, it might sometimes be necessary to control the root cause of acne by reducing the free androgens,” adds Dr. Kanakiya.

The checklist

Because they are hormones, it’s crucial to consult a doctor before you start oral contraceptives. “These pills may not be safe in women with high and uncontrolled blood pressure, a history of stroke or heart attacks, migraines, liver dysfunction, a strong family history of gynaecological cancers, and so on,” warns Dr. Kanakiya. A key rule: do not self-medicate. Consult your gynaecologist before getting on birth control once they’ve assessed your health factors. And while they may help in keeping your skin acne-free, it is only possible to retain that inside-out glow by making—and sustaining—mindful lifestyle modifications like a good diet, proper sleep, and regular exercise.

Also read:

Top 10 myths about the birth control pill, debunked

Seeing excessive hairfall? Your birth control pill may be to blame

What happens if you stop taking birth control pills mid-pack?