Do Women Need Periods?

Enlarge this image Hanna Barczyk for NPR Hanna Barczyk for NPR

Six years of your life. Or 2,190 days. That's about how long the average woman will spend having her periods.

For some women, that's too many days, too many periods.

More women in their 20s and 30s are choosing contraception that may suppress their menstrual cycles, says Dr. Elizabeth Micks, who runs an OB-GYN clinic at the University of Washington in Seattle. "In general, I think views are changing really rapidly," Micks says. "That need to have regular periods is not just in our society anymore."

With traditional birth control, a woman takes a hormone pill for 21 days to stop her cycle. Then she takes a sugar pill for a week, so she can have what looks like a period.

But Micks says, physiologically this isn't a real period at all. And it isn't necessary. "There's absolutely no medical need to have a period when you're on contraception," she says.

So why have women been having all these "fake" periods for decades? "It's actually a historical thing," she says.

One of the doctors who helped invent the pill was Catholic. He thought the pope might accept the pill if it looked like women were having periods.

But the Catholic church never came around to the pill. And when doctors actually asked women if they wanted to have these fake periods, many said they didn't.

Today women have many options if they want to try to suppress their cycles. There's the hormonal IUD, an arm implant and a hormone shot. They can also take some types of birth control pills continuously.

Use of the IUD and implant has risen nearly fivefold in the past decade, a report from the Centers for Disease Control and Prevention found.

And two top medical organizations — the American College of Obstetricians and Gynecologists and the American Academy of Pediatrics — recommend these forms of contraception as the top choice for young women who want birth control. One study found the IUD and implant were nearly 20 times more effective at preventing pregnancies than birth control pills.

But none of these methods are a guarantee for getting rid of periods altogether. "It's not an on and off switch for menstruation," says Paula Hillard, an OB-GYN at Stanford University Medical Center.

Instead, most women have spotting or unscheduled bleeding when they first start these methods. "It can happen without a rhyme or reason, but it tends to improve over time."

For example, with the hormonal IUD, about 50 percent of women don't have periods after a year. But nearly all women will have lighter, shorter and less painful periods after about six months, Hillard says.

Even if a woman hasn't had a cycle in five to 10 years, there's no evidence that suppressing menstruation hurts future fertility, Hillard says. Most women can get pregnant right after they stop using the contraception, except for the hormonal shot — which can decrease fertility for months after it's discontinued, or even a year.

As with all forms of hormonal contraception, there are risks and side effects with these devices, such as an increased risk of blood clots. And some doctors think there isn't enough known about the long-term effects of menstruation suppression, especially with teenagers.

"Important studies, like what are the effects on the breast? What are the effects on bone — haven't been done," says Jerilynn Prior, an endocrinologist at the University of British Columbia.

She says women should think carefully before trying to suppress their cycle. Having a period does serve a purpose, she says: It tells you your reproductive system is working well and that you're not pregnant. It isn't a "disease" that needs to be treated away, she says.

"I think there is value in understanding and appreciating our own intrinsic hormonal cycles," Prior says. "It's our identity."