Period Symptoms by Decade

You change throughout your 20s, 30s, and 40s, so it should be no surprise that your cycles do, too. But are off-schedule, heavy, or otherwise weird periods normal? Here’s how to know—and how to handle it if they’re not.


Photo by Mark Allen Miller

Four hundred fifty: That’s about how many periods you can expect in your lifetime. This monthly event, in which the uterine lining is expelled if an egg is unfertilized, is a complicated business, involving numerous hormonal players that can affect your weight, your temper, and your sex drive.

What Is a Period, Anyway?

Your brain tells the pituitary gland to release two chemical messengers, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), about two weeks after your period starts. The hormones contact the ovaries, triggering a follicle, one of their microscopic egg-containing pouches, to develop and release the egg (a.k.a. ovulation). In the process, the ovaries secrete estrogen and progesterone, which, among other things, tell the uterus to get ready with a lining in case of pregnancy. If the egg isn’t fertilized, your body decides that the fun is over and hormonal levels drop, signaling the uterine lining to shed. And voilà—your period.

When your period changes, you may worry that something is amiss, but most likely you’re perfectly healthy. Here are the shifts that you can expect over the 38-odd years you have a period, and the times they warrant a closer look.

In Your 20s

What’s common: After undergoing some irregular patches in your teens as your ovaries sputter to life, your menstrual cycle usually (but not always) becomes regular. Your period comes every 25 to 32 days and lasts three to seven days. “Yet even a woman whose period comes like clockwork will occasionally have a cycle that varies,” says Angela Dempsey, an ob-gyn at the Medical University of South Carolina, in Charleston.

What to Watch For

  • Skipped periods: Being relatively new to the game, you might assume that disappearing acts are part of the deal. But missed periods could be a sign that you are exercising too much or have lost too much weight—or that you’re pregnant, of course. In rarer cases, missed periods, or ones that vary in intensity and come with weight gain, thinning hair, excessive body hair, or depression, could indicate polycystic ovary syndrome (PCOS), a treatable disorder that affects up to one in 10 women yet goes undiagnosed at least half the time.

See your doctor if: You skip three periods in a row and pregnancy tests are negative.


  • Irregular bleeding: Spotting or heavy bleeding may signal a polyp or a fibroid (both growths in the cervix or the uterus and usually benign) or a cervical lesion (which could be benign or due to a virus or cancer). Low progesterone can also lead to irregular bleeding.

See your doctor if: You’re spotting between cycles or after intercourse, or your periods are much heavier than usual.


  • Painful cramps: Cramps are normal, but women in their 20s report worse ones than older women; scientists don’t know why. You can take a nonsteroidal anti-inflammatory drug (NSAID), like ibuprofen or naproxen, to tame them, or you may be able to ward them off entirely if you take a dose the day before you expect your period. You can also try omega-3 fatty acid supplements, which helped reduce cramps in a study published in the International Journal of Gynecology and Obstetrics in 2012. (Aim for two grams daily.) Early research suggests that vitamin D may also be a cramp-fighter. (Try to get 600 international units, or IU, a day.)

See your doctor if: Cramps get in the way of your daily functioning. This can signal fibroids or endometriosis, an often painful condition in which uterine cells grow outside the uterus.