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Uterine Fibroids - What Happens

Uterine fibroids can grow on the inside wall of the uterus, within the muscle wall of the uterus, or on the outer wall of the uterus. They can alter the shape of the uterus as they grow. Over time, the size, shape, location, and symptoms of fibroids can change.

As women age, they are more likely to have uterine fibroids, especially from their 30s and 40s through menopause (around age 50). Uterine fibroids can stay the same for years with few or no symptoms, or you can have a sudden, rapid growth of fibroids.

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Understanding Uterine Fibroids -- the Basics

The uterus is a muscular, hollow, pear-shaped organ in the pelvis. The lower portion narrows into the cervix, which opens to the vagina. Fibroids are benign (noncancerous) tumors, or growths of the muscle and connective tissue of the uterus. They usually grow slowly and may occur inside the uterus, within the uterine wall, or on the outside surface of the uterus. They occur in 20% to 50% of women of reproductive age. Fibroids are more common in African-American women. Women with fibroids...

Read the Understanding Uterine Fibroids -- the Basics article > >

Fibroids do not grow before the start of menstrual periods (puberty). They sometimes grow larger during the first trimester of pregnancy, and they usually shrink for the rest of a pregnancy. After menopause, when a woman's hormone levels drop, fibroids usually shrink and don't come back.

Complications of uterine fibroids aren't common. They include:

  • Anemia from heavy bleeding.
  • Blockage of the urinary tract or bowels, if a fibroid presses on them.
  • Infertility, especially if the fibroids grow inside the uterus and change the shape of the uterus or the location of the fallopian tubes.
  • Ongoing low back pain or a feeling of pressure in the lower abdomen (pelvic pressure).
  • Infection or a breakdown of uterine fibroid tissue.

Fibroids can cause problems during pregnancy, such as:

  • The need for a cesarean section delivery. This is the most common effect of fibroids on pregnancy.1
  • Premature labor and delivery.
  • Miscarriage. This can happen when fibroids are located inside the uterus.
  • Pain during the second and third trimesters.
  • An abnormal fetal position, such as breech position, at birth.
  • Placenta problems.

WebMD Medical Reference from Healthwise

Last Updated: March 12, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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