OK, first off, if you notice any changes in one or both of your breasts, see a doctor. In particular, any sudden unexplained pain, a lump in the breast or armpit, nipple changes (including discharge), dimpled skin, or a rash need to be checked out asap. It’s not worth waiting around.

Having said that, it’s also not worth panicking: 90% of the time, it won’t be cancer. A lot of breast changes are hormonal, because our bodies might be wonderlands, but they sure do like to mess with us, especially around our periods.

Here are some of the most common hormonal breast changes you might experience, and what to do about them:

Pain

Cyclical mastalgia, or breast pain linked to periods, is super common. It usually shows up a few days before a period and can take the form of anything from a dull ache to a stabbing sensation in one or both breasts, or even an armpit.

How to handle it:

One study found that drastically cutting the amount of saturated fat in your diet (i.e. meat and dairy) significantly improved pre-menstrual breast pain. Another showed that magnesium supplements can help (try a spray formulation – it’s easier to absorb). And there’s anecdotal evidence to suggest that both quitting caffeine and taking evening primrose oil can help in the long-term. For a quick fix, take Tylenol or Advil. And make sure your bra is comfortable and supportive, to be on the safe side.

Fibroadenoma

This is the most common type of breast lump: around 10% of us find one at some point. It will feel firm, with a clearly-defined shape, and move around easily. Fibroadenomas are linked to higher levels of estrogen, which is why they mostly affect young women. Hormonal birth control also makes them more likely.

How to handle it:

See your doctor, who’ll examine your breast and might order an ultrasound, mammogram, or possibly a biopsy if he or she thinks there’s cause for concern (remember, most lumps are benign). If it’s not cancerous, the lump won’t need to be removed, unless it’s painful or continues to grow.

Cysts

Breast cysts are small, fluid-filled sacs. They often feel like a small water balloon, but may also be firm. You can get them any time but they’re more likely between the ages of 35 and 50. They usually get bigger before a period and can cause tenderness, pain, and nipple discharge. They often shrink or even disappear after menopause (unless you’re on hormone replacement therapy).

How to handle it:

Again, head to your doctor, especially if there’s no change after your period. Cysts don’t need to be removed, but if they’re large and uncomfortable, they can be drained. You might be slightly more likely to develop breast cancer in future, so make sure you do a self-exam at the same time every month (ideally not just before your period) and get any changes checked out ASAP.

Fibrocystic breast disease

Not technically a disease, just a whole lot of swelling and lumpiness, which might make your breasts too tender to touch. Around 50% of us get it, usually between the ages of 30 and 60, but doctors aren’t 100% sure why, except that it’s linked to hormonal changes. It often gets worse before a period and again, should improve after menopause.

How to handle it:

Oh, come on, you must have guessed by now: SEE YOUR DOCTOR to rule out any other issues. Try a warm or cold compress for the pain, whichever feels most soothing, plus Tylenol or Advil. Taking evening primrose oil and cutting down on fat and caffeine might also help.

Non-hormonal issues

Just to keep us on our toes, some breast anomalies aren’t related to our hormones at all. Breast pain that doesn’t get better after a period could be caused by muscle strain, heartburn, or even a spinal problem. If you’ve bruised your breast or have some damaged tissue – from a biopsy, for example – you might develop fat necrosis (a small, hard lump). And sometimes a bacterial infection can cause an abscess – a painful collection of pus under the skin, which might require antibiotics. Whatever the cause, consult a medical professional, and you’ll have one less thing to worry about at that time of the month.