Fibroids are abnormal growths that develop in or on a woman’s uterus. Sometimes these tumors become quite large and cause severe abdominal pain and heavy periods. In other cases, they cause no signs or symptoms at all. The growths are typically benign, or noncancerous. They usually develop between the ages of 16 to 50 years. These are the reproductive years during which estrogen levels are higher. Fibroids affect around 30 percent of all women.
Many women have uterine fibroids sometime during their lives. But you might not know you have uterine fibroids because they often cause no symptoms. Your doctor may discover fibroids incidentally during a pelvic exam or prenatal ultrasound. Many women who have fibroids don’t have any symptoms. In those that do, symptoms can be influenced by the location, size and number of fibroids. In women who have symptoms, the most common signs and symptoms of uterine fibroids include:
- Heavy menstrual bleeding
- Menstrual periods lasting more than a week
- Pelvic pressure or pain
- Frequent urination
- Difficulty emptying the bladder
- Backache or leg pains
- pain during intercourse
Types of fibroids
The type of fibroid a woman develops depends on its location in or on the uterus.
Intramural fibroids: Intramural fibroids are the most common type of fibroid. These types appear within the muscular wall of the uterus. Intramural fibroids may grow larger and can stretch your womb.
Subserosal fibroids: Subserosal fibroids form on the outside of your uterus, which is called the serosa. They may grow large enough to make your womb appear bigger on one side.
Pedunculated fibroids: Subserosal tumors can develop a stem, a slender base that supports the tumor. When they do, they’re known as pedunculated fibroids.
Submucosal fibroids: These types of tumors develop in the middle muscle layer, or myometrium, of your uterus. Submucosal tumors aren’t as common as the other types.
It’s unclear why fibroids develop, but several factors may influence their formation.
Hormones: Estrogen and progesterone are the hormones produced by the ovaries. They cause the uterine lining to regenerate during each menstrual cycle and may stimulate the growth of fibroids.
Family history: Fibroids may run in the family. If your mother, sister, or grandmother has a history of this condition, you may develop it as well.
Pregnancy: Pregnancy increases the production of estrogen and progesterone in your body. Fibroids may develop and grow rapidly while you’re pregnant.
Age: Fibroids become more common as women age, especially during the 30s and 40s through menopause. After menopause, fibroids usually shrink.
Ethnic origin: African-American women are more likely to develop fibroids than white women.
Obesity: Women who are overweight are at higher risk for fibroids. For very heavy women, the risk is two to three times greater than average.
Eating habits: Eating a lot of red meat (e.g., beef) and ham is linked with a higher risk of fibroids. Eating plenty of green vegetables seems to protect women from developing fibroids.
Although uterine fibroids usually aren’t dangerous, they can cause discomfort and may lead to complications such as:
- drop in red blood cells (anemia)
- needed due to blood loss.
- placental abruption
- fetal growth restriction
- preterm delivery.