Your period in your teens and 20s

Your period through the decades: What's normal?

It's common for your menstrual periods to change throughout your reproductive years. Here's how to tell whether those changes are normal or not

By Marcia Kaye

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Your period in your teens and 20s

What’s typical: Random, irregular and crampy periods are par for the course in adolescence and early adulthood. True, the “average” menstrual cycle (counting from Day 1 of one period to Day 1 of the next) is 28 days with bleeding that lasts for four days, according to the Society of Obstetricians and Gynaecologists of Canada. But it can take 10 to 12 years after the first period—which normally happens anywhere from age 10 to 14—for the coordination of a young woman’s reproductive system to “grow up” into something resembling regularity, says Dr. Jerilynn Prior, a Vancouver endocrinologist and the scientific director of the Centre for Menstrual Cycle and Ovulation Research at the University of British Columbia. So it’s normal for cycles to fluctuate anywhere from 21 to 35 days, and for bleeding to last between two and six days, says Prior.

Painful cramps are practically a hallmark in this age group, affecting many females under age 30. Renesha Monaco, 22, of Toronto, gets debilitating cramps the first day of every cycle. “I have to schedule my life around my period, and usually I can’t work,” says the radio promotions rep. “My fiancé’s mother says she went through the same thing until she had a baby.”

Monaco’s future mother-in-law is on to something, says Prior. “Menstrual cramps are related to higher pressure inside the uterus as the muscle of the uterine wall contracts with flow. Younger women who haven’t had a pregnancy or worn an IUD have a tighter cervix, and this generates greater pressure and more cramps.” But even women who haven’t been pregnant may experience improvement after age 30. Prior says there’s emerging research that younger women’s cycles involve higher estrogen and lower progesterone levels.

This hormonal environment encourages the formation of prostaglandins—fatty acids that promote uterine contractions, causing cramps. Prior says the key is staying ahead of the pain. “When you get that heavy pelvic feeling—even before the cramps start or pain starts—take two ibuprofen, then a regular dose every four to six hours.”

It’s not unusual for young women to also have lengthy dry spells. “I didn’t have my period for the whole nine months of my first year of university,” says Prior. Causes of skipped or late periods (besides pregnancy) include stress from a major change, breakup or illness; an eating disorder; or simply not getting enough calories or protein. Scanty periods—meaning they last little more than one or two days and you need only a panty liner—could be quite normal in a thin, active young woman. If you’re on oral contraceptives, mid-month spotting is usually the result of a low-dose pill or a skipped pill.

Causes for concern: Get checked out for any new pelvic pain, especially at other times in your cycle. “You need to rule out sexually transmitted infections and pelvic inflammatory disease as well as the possibility of underlying issues including endometriosis and even irritable bowel syndrome,” says Jennifer Tomiuk, nurse practitioner at the Women’s Health Clinic in Winnipeg.

If your cycle is normally longer than 35 days or you go for months without a period (and you’re not pregnant or breastfeeding), you may not be producing enough estrogen, leaving you at risk for future bone loss. Or it could be thyroid disease, diabetes or polycystic ovarian syndrome, which can all cause missed periods, Tomiuk advises.