The uterus is where the fertilized egg implants itself, developing and growing inside an amniotic sac within the organ. During pregnancy, it is normal for the uterus to change and enlarge, growing to accommodate the developing baby. A distended uterus in a woman who is not pregnant, however, is something to be concerned about. There are a number of medical conditions that can cause an enlarged uterus.
Leiomyomas
Leiomyomas are also known as uterine fibroids. They are the most common tumor of the uterus and are benign because they do not invade nearby tissue. Many women have small ones and do not have any symptoms. Some women do have symptoms that may include pain, heavy bleeding during or between their menstrual cycles, constipation and frequent urination. Leiomyomas that press on the intestines can cause constipation. If they press on the urinary bladder, this can result in frequent urination. Leiomyomas can also affect pregnancies. Women may lose their babies, give birth prematurely or need a cesarean section because the fetus is not in the proper position. This tumor can also prevent pregnancies.
Adenomyosis
In this disorder, endometrial glands are present in the muscular layer of the uterus, where they are not usually located. They may be all throughout the uterus or they may collect in several areas and form nodules. Approximately 20 percent of women have adenomyosis, writes Jamie Drinville, M.D., in "Current Diagnosis & Treatment: Obstetrics & Gynecology." The glands make the smooth muscle that is near them increase in size. This can lead to an enlarged uterus. Most women with this condition also have heavy bleeding during their menstrual cycle.
Hematometra
Hematometra is a disorder where some abnormality obstructs the menstrual flow of blood from leaving the uterus. Blood stays inside the uterus and the uterus enlarges. The obstruction can be due to a congenital abnormality, tumor, radiation treatment, scarring or Asherman's syndrome, as explained in "Williams Obstetrics" by John Schorge, M.D. Asherman's syndrome is a disorder where adhesions develop inside the uterus as a result of infections, surgery or a D&C procedure. Women may have pain, little or no menstrual bleeding, increased heart rate and fever.
References
- "Current Diagnosis & Treatment: Obstetrics & Gynecology"; Alan DeCherney, M.D., Lauren Nathan, M.D., et al.; 2007
- Merck: Uterine Fibroids
- "Williams Obstetrics"; F. Gary Cunningham, M.D., Kenneth Leveno, M.D., Steven Bloom, M.D., et al.; 2010
