It seems like only yesterday you were snickering in health class as you learned about feminine hygiene and your impending first period. Now here you are in the prime of life—and it's already time to think about your last.
By your 40s—and sometimes earlier, for the 1 to 5 percent of women headed for premature menopause—important menstrual-cycle changes are already on the way. Here's what to know.
A skipped or heavy period might be your first sign of menopause.
Your menstrual cycle until menopause isn't a now-you-see-it, suddenly-you-won't deal. "The ovary doesn't stop, boom!" says Sandra Carson, a professor of ob-gyn at Brown University and medical director of the Center for Reproduction and Infertility at Women's and Infants Hospital of Rhode Island.
Most women experience gradual menstrual irregularity during the phase known as perimenopause, the three to five years before menopause. Estrogen levels start falling even earlier, as eggs disappear from the ovaries, though we don't notice. Ongoing hormonal shifts finally become obvious in the form of changing periods.
Usually this means lighter and less frequent, but "normal" reactions are surprisingly variable. A woman's periods may turn longer than usual, shorter than usual, space farther apart, or in some months be skipped entirely. Some women begin to have bouts of heavy bleeding. Others spot between periods.
Tracking their timing, length, and nature now can help you notice the changes.
Bleeding changes are normal, but you shouldn't assume they're normal.
Even though the majority of women develop some kind of menstrual irregularity in their 40s as the body closes shop on reproduction, heavy bleeding is one symptom you should always report to your doctor.
At minimum, heavy periods can lead to anemia or disrupt your ability to conduct daily life. (Example: a teacher or a surgeon who must spend hours on her feet without a break.) But heavy bleeding can also flag other treatable conditions that can affect women of any age, including fibroids, polyps, ovarian cysts, an overgrowth of the endometrium (uterine lining), or, rarely, uterine cancer.
"Heavy" periods can feel different from woman to woman.
The medical definition of a heavy period (menorrhagia) is more than 80 ccs (cubic centimeters) of blood, or about three ounces, according to Carson. (Most women lose about six teaspoons of blood per cycle.) But who measures her flow, let alone knows what 80 ccs looks like? And if you're someone who's always had intense periods, what should you look for?
Trust what seems like a change for you. "After you've been menstruating for 30 years, you know when there's a change," Carson says.
Also look for: clotting, using more than one high-absorbency pad at a time, combining a tampon plus a pad, needing to change pads hourly, bleeding steadily for more than seven days. The American College of Obstetrics and Gynecologists also recommends telling your doctor if you're bleeding more often than every three weeks or you bleed after having sex.
There's no link between menstrual difficulty in your reproductive years and menstrual difficulty in perimenopause.