It can take a while for a girl's menstrual cycle to settle into something regular. Most of the time, if periods aren't regular it's because a girl's body is still developing. It might be confusing or annoying, but it's totally normal.
Sometimes, though, changes in blood flow can be a sign that something more serious might be going on.
Dysfunctional uterine bleeding (DUB) is the name doctors use to describe when something isn't quite right with a girl's periods. Doctors also sometimes call DUB "abnormal uterine bleeding" (AUB). Like lots of medical names, it can sound worse than it is. Most of the time, DUB isn't something to worry about.
If a girl has DUB, it might mean her periods last longer or have more bleeding than normal. Or, it might mean the opposite — that her bleeding is light and her periods aren't coming as often as they should.
Because DUB isn't usually a problem, doctors often don't do anything about it. But sometimes they'll take action if they worry that DUB might cause another problem. For example, doctors may worry that a girl could get anemia if she is bleeding more than she should.
Most of the time, DUB happens because of changes in the body's hormone levels.
For teen girls, one of the most common causes of hormone changes is when the body doesn't release an egg from one of the ovaries. This is called anovulation.
The release of an egg is part of the hormone process that makes up the menstrual cycle. If a girl's body doesn't release an egg, too much extra blood and tissue can build up in the lining of her uterus. When that lining eventually leaves the body, a girl can have more than normal amounts of bleeding. This bleeding might happen as part of a period or in between periods.
Anovulation is most likely to happen after a girl first starts getting her period. That's because the ovaries aren't fully developed yet. It can last for several years until a girl's periods become regular.
Other things can lead a girl to develop DUB. Some illnesses (like thyroid disease or polycystic ovary syndrome) can mess with the body's hormones. Problems like compulsive exercise, not eating healthy foods, or too much stress can cause hormone changes. Some severe cases of DUB are caused by bleeding disorders such as von Willebrand disease.
Every woman has a heavy period from time to time. How do you know if it's dysfunctional uterine bleeding? Only a doctor can tell for sure, but there are some signs that bleeding might not be normal.
One thing that can alert you to problems is the 1-10-20 test:
If you notice any of these things, call your doctor. Bleeding in between periods or after sex also can be a sign of DUB.
If your period stops for more than 3 months, ask your doctor about that, too. If you're not bleeding, the lining of the uterus can keep building up. Eventually it will need to flow out.
A doctor will want to rule out other health problems before deciding a girl has DUB. For example, doctors might find out that a girl with heavy periods has a bleeding disorder like von Willebrand disease.
To diagnose DUB, doctors will ask questions about periods and bleeding. Expect your doctor to ask the date your last period started.
A doctor also might ask questions that don't seem connected to bleeding — like about recent weight changes or if you have ever had sex. Doctors ask these questions because conditions like polycystic ovary syndrome and some STDs can cause abnormal bleeding. If they're not treated, they may lead to more serious health issues, like infertility (not being able to have a baby).
Girls who have had sex and miss a period need to see a doctor. Missed periods could be a sign of pregnancy as well as a sign of DUB. If you have heavy bleeding or bleeding between periods, it could be an infection or other problem. For example, an ectopic pregnancy (when a pregnancy implants someplace other than the uterus) can cause bleeding, and can be life-threatening.
A doctor might do a physical exam and maybe a pelvic exam. Sometimes doctors order blood tests or ultrasound exams. Blood tests also can show if a girl has anemia (fewer red blood cells than normal).
To decide if DUB is serious enough to need treatment, a doctor will look at a girl's hemoglobin level. This is a way to see if a girl has anemia or not:
Most girls just need time for their bodies to adjust to their hormones. Eventually, their menstrual cycles get regular naturally. If you're ever worried that your period might not be normal, talk to your doctor.
Reviewed by: Rupal Christine Gupta, MD
Date reviewed: April 2015
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