Period acne: why it happens and how to prevent it

Period acne is a flare of pimples that comes at the same point in the menstrual cycle each month, most often in the week before bleeding starts. It is one of the clearest signs that hormones are playing a part in someone's acne. This guide covers what studies have measured about the monthly flare, what is known about the hormones behind it, and how to stop the same breakout from coming back every month. For the full treatment plan, see the hormonal acne treatment guide.

Skinli gives general education and is not a doctor. If your periods are irregular or your acne is severe, see a doctor.

How common period acne is

Several studies have measured the monthly flare, and they agree that it is common in women with acne:

Study	Who took part	What it found
Journal of the American Academy of Dermatology, 2001	400 women aged 12 to 52	44% had acne flares before their periods. Women older than 33 had flares more often than women aged 20 to 33
Archives of Dermatology, 2004	Adult women aged 18 to 44 with regular periods and no acne treatment	63% had a 25% rise in inflamed spots in the late part of the cycle
Journal of Clinical and Aesthetic Dermatology, 2014	Adult women seeing a dermatologist for acne	65% said their acne was worse with their periods
International Journal of Women's Dermatology, 2020	56 women aged 25 and older with acne	58.9% had a flare before their periods

The numbers differ because the studies asked different groups in different ways. In the 2001 study, taking birth control pills did not change how often women had flares.

When in the cycle it happens

The menstrual cycle has two halves. The first half runs from the first day of bleeding to the release of an egg. The second half, called the luteal phase, runs from the egg's release to the next period.

Period acne sits mostly in that second half. The 2004 study counted spots through two full cycles and found the rise in the late luteal phase, the days just before bleeding. In the 2014 survey, the women with a monthly flare described its timing this way:

• 56% said acne was worse in the week before their period
• 17% said it was worse during their period
• 3% said it was worse after their period
• 24% said it was worse throughout the cycle

A 2017 study of 32 women with monthly flares found that the flare was mostly red, raised bumps, called papules. The average number of papules rose from 13.7 to 20.2 during the flare.

The hormones behind it

The American Academy of Dermatology (AAD) says women's hormones change around their periods, and that changing hormone levels can lead to breakouts. NIAMS, part of the US National Institutes of Health, explains how hormones reach the skin: androgens, the male-type hormones that women also make, enlarge the oil glands and make them produce more oil. More oil means more plugged pores.

Researchers have not yet found which hormone causes the monthly flare. A 2025 review of adult female acne describes one study in which acne got worse as the female hormones estradiol and progesterone fell, and as the balance shifted toward androgens. Both female hormones drop in the days before a period. The same review says the role of androgens in adult acne is unclear, because most women with acne have normal androgen levels on blood tests.

In plain words, one study found that acne got worse when female hormones fell, and that fall happens before every period. Researchers are still working out why.

What period acne looks like

Period acne is ordinary acne that follows a calendar. It often shows up as:

• Red, tender bumps and pimples with pus, as the 2017 study found
• Spots on the lower face, chin and jawline, a pattern the AAD links to hormonal acne
• Deep, sore spots in some women, which the AAD says hormonal therapy can treat on the lower face, jawline and neck

If your monthly spots sit mostly along the jaw, the jawline acne guide covers that pattern. If they come with irregular periods or new hair growth, read the PCOS acne guide.

How to prevent period acne

Treat every day, including the clear weeks

Treating only the spots that appear each month does nothing for the next flare. The AAD says to apply a thin layer of acne medicine to all acne-prone skin, because that treats the acne you have and prevents the next breakout.

The AAD's dermatologists recommend one product with one of these active ingredients for mild to moderate adult acne:

Ingredient	What the AAD says it does
Adapalene	Clears blackheads, whiteheads and pimples
Azelaic acid	Fights acne and fades dark spots
Benzoyl peroxide	Treats mild pimples. Start at 2.5% to limit dryness
Salicylic acid	Unclogs pores. Works best on whiteheads and blackheads

Use it for 6 to 8 weeks before you judge it, which spans more than one full cycle. The AAD says to expect fewer breakouts in 4 to 8 weeks and clearing at 16 weeks if the product works.

Track the pattern

Write down the first day of each period and take a photo of your face on the same days each week. After two or three cycles you will see whether the flare lines up with your cycle, and a doctor can use the record. The progress photo guide shows how to take photos that are easy to compare.

Habits that may help

• Stress. The AAD says stress may make acne worse, and that the body makes more androgens under stress.
• Food. The AAD says small studies link foods that raise blood sugar fast to more acne, while other studies found no link. Does diet cause acne? sets out the evidence.
• Picking. The AAD says picking and popping make acne worse and raise the risk of scars.

The sources Skinli reviewed name no natural product proven to prevent the monthly flare. The natural remedies guide covers what has been studied.

Period acne on the pill

Some women still get a monthly flare while taking birth control pills. In the 2014 survey, 35% of the women with period acne were taking a birth control pill. In the 2001 study, women taking the pill had monthly flares as often as women who were not. The AAD says some pills are FDA approved to treat acne. The NIH's child health institute, NICHD, says some progestins, the second hormone in many pills, can cause oily skin and acne. A prescriber can say whether your current pill is a good fit for acne. Do not stop or switch a birth control pill without talking to the person who prescribed it, because it also prevents pregnancy.

When the monthly pattern changes

A change in the pattern can point to something new:

• Periods that become irregular or far apart, with acne and extra hair growth, are symptoms the NHS lists for PMOS, the condition once called PCOS.
• Cycles that get longer or shorter in your 40s are a common sign of perimenopause, the years before the last period, according to the American College of Obstetricians and Gynecologists. See menopause acne.
• A missed period with new acne is a reason to take a pregnancy test. See pregnancy acne, because several acne medicines must stop in pregnancy.

When the monthly flare keeps coming back

If a steady routine has not stopped the flare after two or three cycles, a dermatologist has hormonal options for women. The AAD lists two signs of hormonal acne on its treatment page: stubborn acne on the lower face, chin and jawline, and breakouts that come predictably during your period. For women with these signs, it names:

• Birth control pills. The AAD says the FDA has approved some for treating acne, and that women notice improvement in 2 to 3 months. See birth control for acne.
• Spironolactone. The AAD says women see fewer breakouts and less oil within a few weeks. See spironolactone for acne.

Both are prescription medicines. A prescriber decides whether they are safe for you after asking about your health.

When to see a doctor

See a doctor if:

• Your periods are irregular, far apart or have stopped
• You have new hair growth on your face, chest or belly
• Your monthly spots are deep and painful, or leave scars or dark marks
• Acne has not improved after two or three months of daily treatment

The AAD says dark or red spots can stay for months after acne clears, and that treating acne early lowers the risk of scars. Skinli's free acne plan gives you a starting routine from a photo, which you can keep through every week of your cycle.