Anatomy The uterus is a hollow, thick-walled, pear-shaped muscular organ in the female reproductive system. During pregnancy the uterus expands to accommodate a developing embryo. It is located between the urinary bladder in front and the rectum behind, and sits above the vagina. The lower narrow portion of the uterus is called the cervix and it protrudes downward into the opening of the vaginal canal. The vaginal canal extends downward to the external female genitalia. The uterine tubes, or Fallopian tubes, extend from either side of the uterus and act as a channel for eggs from the ovary to travel to the uterus. When an egg is fertilized (joined with sperm), it becomes embedded in the wall of the uterus (whose lining becomes thickened) where the fertilized egg grows into an embryo and later a fetus. If an egg is not fertilized, the thickened uterine lining sloughs off in a process known as menstruation.
Function The reproductive function of the uterus is to accept a fertilized ovum which passes through the utero-tubal junction from the fallopian tube. It then becomes implanted into the endometrium, and derives nourishment from blood vessels which develop exclusively for this purpose. The fertilized ovum becomes an embryo, develops into a fetus and gestates until childbirth. Due to anatomical barriers such as the pelvis, the uterus is pushed partially into the abdomen due to its expansion during pregnancy. Even during pregnancy the mass of a human uterus amounts to only about a kilogram (2.2 pounds).
Uterus during pregnancy When a woman becomes pregnant, blood flow increases to the uterus and the uterus increases in size, continuing to enlarge with the baby. After the baby is born, the uterine muscle fibers start to contract, and over the course of eight to 10 weeks it shrinks back to just a little bigger than it was before she got pregnant. Think of the uterus as a baby incubator. It expands to accommodate the baby and also works with the placenta to supply the baby with nutrients. When it's time for the baby to be born, the uterus contracts to expel the baby and the placenta. It then shrinks back down and gets ready to start the whole cycle again.
Problems that can affect the uterus Noncancerous growths in the uterus, called fibroids, which can cause pain and bleeding. Endometriosis, a condition in which the tissue that forms the lining of the uterus grows outside the uterus. Heavy bleeding each time you have your period or between periods. Hormonal imbalances. Unexplained pelvic pain.
Treatment options for common uterine conditions Fibroids There are several treatments to choose from if you have fibroids. It depends on how big the fibroids are, where they are, and whether you are pregnant or want to become pregnant. Watchful waiting may be all the treatment you need if your fibroid is small and you do not have any symptoms. You will need regular visits to your doctor for a pelvic exam to monitor the growth of the fibroid. Nonsurgical treatments for fibroids include hormones and pain relief medicines. Taking gonadotropin releasing hormone (GnRH) can cause fibroids to shrink. This may make surgery easier, or it may be used instead of an operation. Your doctor may prescribe ibuprofen (for example, Advil), acetaminophen (for example, Tylenol), or another medicine to relieve pain. Surgical treatments for fibroids include hysterectomy and myomectomy. Hysterectomy is usually recommended when the fibroids are causing symptoms, when they have grown rapidly, or when the fibroids are large (as large as a grapefruit). Myomectomy is an operation to remove a fibroid tumor without taking out the uterus. This means that pregnancy is still possible, although a Cesarean section may be necessary. Another option is laser surgery, which usually is an outpatient procedure. With laser surgery, the doctor uses a high-intensity light to remove small fibroids. Depending on the location of the fibroid, it may be possible to remove it during a laparoscopy. Or, the doctor may put a thin tube (called a hysteroscope) with a laser through the vagina and into the uterus. The tube may have a small scraper to scrape away the fibroid from the wall of the uterus.
Endometriosis Nonsurgical treatments include: Medicine, including hormones. There are two types of hormone therapy: those that will make your body think it is pregnant and those that will make your body think it is in menopause. Both are meant to stop the body from producing the messages that cause the endometrial tissue to grow. Birth control pills may be used for a few months to try to shrink the adhesions in women who want to become pregnant. Other hormones-GnRH and danazol-also may help relieve the pain of endometriosis. Doctors sometimes prescribe pain relievers, such as ibuprofen (for example, Advil and Motrin) or, for severe pain, codeine. Other nonsurgical options include watchful waiting and changes in diet and exercise. Several types of surgery are used to treat endometriosis, including: Laser laparoscopy, in which a cut is made in the abdomen and adhesions are removed, either by laser beams or electric cauterization. Hysterectomy, which may not cure endometriosis. Unless the ovaries are removed also, they will continue to produce estrogen. This may encourage endometrial tissue to grow in other areas of the body. Bowel resection, which means taking out a section of the bowel, if endometriosis is affecting the bowel. Cutting certain nerves, called the sacral nerves, in the lower back to relieve pain.
Heavy menstrual bleeding
Birth control pills or other medicines may be helpful.
Another choice is watchful waiting.
A surgical procedure called endometrial ablation may help to relieve very heavy menstrual bleeding. Endometrial ablation causes sterility (inability to become pregnant), but it does not trigger menopause. The long-term effects of endometrial ablation are unknown.
Severe pelvic pain Several types of medicine are used to treat painful cramps. These include: Over-the-counter pain relievers, such as aspirin, ibuprofen, naproxen (for example, Aleve), or acetaminophen may be helpful. If over-the-counter medicines don't work, your doctor can give you a prescription for a stronger pain reliever, such as codeine. Birth control pills or other medicines may be used to reduce cramping. Surgery usually is not necessary if severe menstrual pain is the only problem.