Uterine Fibroids

Uterine fibroids can grow on the Reference inside wall of the uterus Opens New Window Reference Opens New Window, Reference within the muscle wall of the uterus Opens New Window Reference Opens New Window, or on the Reference outer wall of the uterus Opens New Window Reference Opens New Window. 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.

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.^{Reference 1} 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:

• Reference Anemia Opens New Window from heavy bleeding.
• Blockage of the urinary tract or bowels, if a fibroid presses on them.
• Reference Infertility Opens New Window, 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 Reference cesarean section Opens New Window delivery. This is the most common effect of fibroids on pregnancy.^{Reference 2}
• 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 Reference breech position Opens New Window, at birth.
• Reference Placenta Opens New Window problems.

© 1995-2011, Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.