Skip to content
My WebMD Sign In, Sign Up

Women's Health

Font Size

5 Things You Didn't Know About Your Period

Even well-informed women have questions about their menstrual cycle. Here are answers to the most common questions encountered by gynecologists.
By
WebMD Feature
Reviewed by Louise Chang, MD

So you've had your period for a few years -- or for decades -- and you think you're in the know. Then up pops a question from you or one of your friends that no one can answer with certainty.  That doesn't surprise gynecologists, who say they often field menstrual cycle questions from their patients.

Here, three top gynecologists talk about the most common questions they get about periods and what they tell their patients.

Recommended Related to Women

Are You Too Sensitive?

By Sarah MahoneyNo, we're not picking on you - just trying to make you feel better. Seven tips to help you roll with the punches this season. There was a carpool mix-up: I thought it was my night to pick up the kids outside the gym; another parent thought it was his. "What happened?" he snarled, shaking his head. "Why are we both here right now?" As chauffeuring snafus go, this was small potatoes. It isn't like we left our boys standing in the snow. So why am I still smarting over his tone...

Read the Are You Too Sensitive? article > >

1. Why do I get PMS?

PMS, or premenstrual syndrome, occurs because your body is sensitive to hormonal changes, says Richard P. Frieder, MD, a staff gynecologist at Santa Monica UCLA & Orthopaedic Hospital in Santa Monica, Calif. "In the week or 10 days before your period comes, hormone levels -- progesterone and estrogen -- are changing rapidly," he says.

That can cause symptoms such as bloating, mood swings, headache, breast tenderness, and fatigue in some women, he says.

As many as 90% of women experience some symptoms before their period, according to a study in the Archives of Internal Medicine, but many fewer -- 20% or less -- have symptoms severe enough to interfere with normal activities and relationships and be termed PMS.

Whether you have just a few mild symptoms or full-blown PMS, Frieder advises: "Make your body as healthy as possible. Try to get exercise every day, especially on the day you get PMS. Drink lots of water so you are not dehydrated. Eat every couple of hours. Stay away from alcohol and caffeine."

From there, he believes in treating individual symptoms. If moodiness is a problem, for instance, he sometimes prescribes calcium supplements.

A high intake of calcium and vitamin D seems to reduce the risk of getting PMS, according to a study that followed more than 3,000 women and was published in 2005 in the Archives of Internal Medicine. Women who ate about four servings a day of low-fat milk or dairy foods or fortified orange juice were less likely than those who didn't to develop PMS over the 10-year follow-up.

Some experts have suggested that vitamin D and calcium deficiencies lead to the PMS.

Often, women with more severe premenstrual symptoms report amazing relief when they go on birth control pills, says Frieder, who is also an assistant clinical professor of obstetrics and gynecology at the University of California Los Angeles David Geffen School of Medicine. Low doses of antidepressants are sometimes prescribed to improve the mood swings.

2. Why are my cycles irregular?

Some women don't ovulate regularly and therefore have irregular periods, Frieder says. Stress and illness, for instance, can adversely affect the cycle.

But it's important to know the definition of a "regular" cycle before deciding you are having irregular periods, Frieder says. What some women think is an irregular cycle may not be, he says. A "regular" cycle, Frieder says, means one that is between 25 and 35 days -- counting from the first day of bleeding to the start of your next period.

Today on WebMD

woman looking in mirror
Article
Woman resting on fitness ball
Evaluator
 
woman collapsed over laundry
Quiz
Public restroom door sign
Slideshow
 
Couple with troubles
Article
Bone density illustration
VIDEO
 
Young woman being vaccinated
Slideshow
woman holding hand to ear
Slideshow
 
Blood pressure check
Slideshow
mother and daughter talking
Evaluator
 
intimate couple
Article
puppy eating
Slideshow