- Home
- Parents Home
- Allergy Center
- Asthma Center
- Cancer Center
- Diabetes Center
- A to Z
- Emotions & Behavior
- First Aid & Safety
- Food Allergy Center
- General Health
- Growth & Development
- Flu Center
- Heart Health
- Helping With Homework
- Infections
- Diseases & Conditions
- Nutrition & Fitness Center
- Play & Learn Center
- School & Family Life
- Pregnancy & Newborn Center
- Pregnancy & Baby
- Q&A
- Recipes
- Sports Medicine Center
- Doctors & Hospitals
- Videos
- Para Padres
- Home
- Kids Home
- Asthma Center for Kids
- Cancer Center for Kids
- Movies & More
- Diabetes Center for Kids
- Getting Help
- Feelings
- Puberty & Growing Up
- Health Problems of Grown-Ups
- Health Problems
- Homework Center
- How the Body Works
- Illnesses & Injuries
- Nutrition & Fitness Center for Kids
- Recipes & Cooking for Kids
- Staying Healthy
- Stay Safe Center
- Relax & Unwind Center
- Q&A for Kids
- The Heart
- Videos for Kids
- Staying Safe
- Kids' Medical Dictionary
- Para Niños
- Home
- Teens Home
- Asthma Center for Teens
- Be Your Best Self
- Cancer Center for Teens
- Diabetes Center for Teens
- Diseases & Conditions (for Teens)
- Drugs & Alcohol
- Expert Answers (Q&A)
- Flu Center for Teens
- Homework Help for Teens
- Infections (for Teens)
- Managing Your Medical Care
- Managing Your Weight
- Nutrition & Fitness Center for Teens
- Recipes for Teens
- Safety & First Aid
- School & Work
- Sexual Health
- Sports Center
- Stress & Coping Center
- Videos for Teens
- Body
- Mind
- Para Adolescentes
What Does Menstruation Mean?
Menstruation
Say: men-STROO-ay-shun
Menstruation is often called having a "period." A period is the 2–7 days that a girl or woman has her menstrual flow, which is when blood and tissue leave her body through her vagina.
Why does this happen? Each month, blood and tissue build up in the uterus to prepare for a fertilized egg in case a woman becomes pregnant. (The uterus is the place inside a woman's body where a baby will grow.) If the egg isn't fertilized, that lining leaves the body through the vagina and the girl or woman has her period.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
© 1995- The Nemours Foundation. KidsHealth® is a registered trademark of The Nemours Foundation. All rights reserved.
Images sourced by The Nemours Foundation and Getty Images.