Home > Teens > Puberty and Sex > Changes During Puberty > Irregular Menstruation

Expert Iconexpert advice MORE

Irregular Menstruation

Pediatrics Expert Advice from Henry Bernstein, M.D.

Q: My 11-1/2-year-old daughter recently started menstruating for the first time. It lasted about four days and the flow seemed to be normal. However, she started again within about 18 days from the last day of her first period. Is that normal?

A: Yes, that sounds perfectly normal for someone going through puberty. Young girls are beginning puberty earlier than previously believed and are having their first period somewhat earlier as well. As puberty continues, most girls have their first menstrual period two years after the onset of breast development. Even after they have their first period, girls continue to grow taller and "regular" menstrual cycles usually do not happen for one to two years. During these first two years, one half to three quarters of cycles early on are anovulatory (no egg is released from the ovary), which accounts for this variability. Reassuring your daughter that what she is experiencing is normal should help during this sensitive time for teenagers.

The glands in the body and the hormones that communicate between the glands need to be functioning together to then have "regular" menstrual cycling. Remember that a menstrual cycle is defined as the number of days between the first day of bleeding with the last menses and the first day of bleeding with the next menses. The normal menstrual cycle lasts between 21 and 35 days. Changing cycle lengths from month-to-month can be normal. Most women usually bleed for three to seven days. If her bleeding seems excessive, too frequent, lasts more than a week, or if she has other associated symptoms, I would contact her physician.

More on: Expert Advice

Henry Bernstein, M.D., is currently the associate chief of the Division of General Pediatrics and director of Primary Care at Children's Hospital, Boston. He also has an academic appointment at Harvard Medical School.

Please note: This "Expert Advice" area of FamilyEducation.com should be used for general information purposes only. Advice given here is not intended to provide a basis for action in particular circumstances without consideration by a competent professional. Before using this Expert Advice area, please review our General and Medical Disclaimers.

stay connected

Sign up for our free email newsletters and receive the latest advice and information on all things parenting.

Enter your email address to sign up or manage your account.

Facebook icon Twitter icon Follow Us on Pinterest

editor’s picks


Healthy Smile Checklist for Kids
Have better dental check-ups with this free printable checklist that helps keep your child flossing, brushing, and smiling! Brought to you by Philips Sonicare.

Kindergarten Readiness App
It's kindergarten registration time! Use this interactive kindergarten readiness checklist, complete with fun games and activities, to practice the essential skills your child needs for this next big step. Download the Kindergarten Readiness app today!

Top 10 Earth Day Books for Children
Celebrate the environment by reading some of these great children's books about Earth Day, recycling, planting trees, and all things green!

Prom Dress Trends for 2014
Check out 2014 prom dress trends inspired by celebrities’ red carpet looks, but with a price tag under $100!