Abnormal Uterine Bleeding

This information is useful for children and adults
middle aged woman looking thoughtful, possibly worried about abdominal uterine bleeding

Abnormal uterine bleeding (AUB)—or menstrual bleeding that is unpredictable in timing, amount or duration—is a common problem among women. This can range from light spotting during or in between menstrual periods, or extremely heavy blood flow during the monthly period.

As part of a woman’s monthly menstrual cycle, the mucous membranes that line the uterus prepare for an egg to be fertilized and settle there. If that doesn’t happen (no egg is fertilized), the body sheds the lining along with some blood. Typically lasting five to seven days, this is what is called your “period.”  

Bleeding that occurs at any other time of the month is considered AUB. The usual cause is a hormone imbalance, but other potential causes include structural abnormalities (fibroids, polyps, adenomyosis), anovulation (when ovulation doesn’t occur) and bleeding disorders. Additionally, certain medications or cancer may result in unusual bleeding patterns.

“There can be cramping and pain associated with the bleeding, and these symptoms can be disruptive and sometimes debilitating,” says Amanda Kallen, MD, a Yale Medicine obstetrician-gynecologist and specialist in reproductive endocrinology and fertility.

Uncomfortable and inconvenient as it is, UAB is quite common—and can usually be treated and controlled. “It’s a large part of what we see in our practice,” says Dr. Kallen, who is also director of the Yale Medicine Recurrent Pregnancy Loss Program. “Often, women who have tried different therapies without success will be referred to us for a more in-depth management strategy.”