Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

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.

4. If I get my period, can I be sure I am not pregnant?

You can't be 100% sure, says Dolan. "It could be bleeding in early pregnancy," she says. "You can't always tell the difference." Pay attention to whether it progresses as a regular period.

She advises women: If you have other symptoms such as nausea, check with your doctor. A pregnancy test might be wise.

5. If I leave in a tampon too long, am I at risk for toxic shock syndrome?

Toxic shock syndrome, or TSS, a life-threatening illness caused from a bacterial infection, made headlines in 1980 when an outbreak occurred that mostly involved young women who had been using a specific brand of very absorbent tampons (the brand is now off the market.) The bacteria produce toxins that cause toxic shock syndrome.

TSS is marked by a sudden onset of fever, chills, diarrhea, vomiting, muscle aches, and rash. Some experts say that very absorbent tampons, when left in place for a long time, become a breeding ground for bacteria and cause the syndrome. Others say how long you leave in a tampon doesn't increase your risk of getting sick.

Ideally, how long should you leave in a tampon? "Follow what the package insert says,'' suggests Deidre Defoe, MD, clinical director of Rachel's Well, a nonprofit women's health care organization based in Virginia.

On the web site of one popular tampon brand, for instance, it recommends changing the tampon at least every four to eight hours.

Know that the condition is rare. In the U.S., about one or two of every 100,000 women ages 15 to 44 get toxic shock syndrome annually, according to the CDC.

Many experts say they have never seen a case since they have been in practice. "Toxic shock is something everyone learns about in medical school," Defoe says. But Defoe says she has yet to see a case.

1 | 2 | 3
Reviewed on February 23, 2009

Today on WebMD

hands on abdomen
Test your knowledge.
womans hand on abdomen
Are you ready for baby?
birth control pills
Learn about your options.
Is it menopause or something else?
woman in bathtub
bp app on smartwatch and phone
estrogen gene

Send yourself a link to download the app.

Loading ...

Please wait...

This feature is temporarily unavailable. Please try again later.


Now check your email account on your mobile phone to download your new app.

Blood pressure check
hot water bottle on stomach
Attractive young woman standing in front of mirror