What is uterus

Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. The uterus, also known as the womb, is the hollow, pear-shaped organ in the female pelvis in which fertilization of an ovary egg , implantation of the resulting embryo, and development of a baby take place. It is a muscular organ that both stretches exponentially to accommodate a growing fetus and contracts in order to push a baby out during childbirth.

The lining of the uterus, the endometrium, is the source of the blood and tissue shed each month during menstruation. Shaped like an inverted pear, the uterus sits behind the bladder and in front of the rectum.

The uterus is supported in the pelvis by the diaphragm , the perineal body, and a collection of ligaments, including the round ligaments. The uterus performs multiple important functions in the reproductive cycle, fertility, and childbearing.

During a normal menstrual cycle, the endometrial lining of the uterus goes through a process called vascularization during which tiny blood vessels proliferate, leaving the lining thicker and rich with blood in the event the egg released during that cycle is fertilized. If this does not happen, the uterus sheds the lining as a menstrual period.

If conception occurs, the fertilized egg the embryo burrows into the endometrium from which the maternal portion of the placenta , the decidua basalis, will develop. As a pregnancy progresses, the uterus grows and the muscular walls become thinner, like a balloon being blown up, to accommodate the developing fetus and the protective amniotic fluid produced first by the mother and later by urine and lung secretions of the baby.

During pregnancy, the muscular layer of the uterus begins contracting on-and-off in preparation for childbirth. These "practice" contractions, Braxton-Hicks contractions, resemble menstrual cramps; some women don't even notice them. They are not the increasingly powerful and regular contractions that are strong enough to squeeze the baby out of the uterus and into the vagina. After a baby is born, the uterus continues to contract in order to expel the placenta. It will continue to contract in the coming weeks to return the uterus to its normal size and to stop the bleeding that occurs in the uterus during childbirth.

The uterus can be subject to any of a number of health issues. The most common uterine conditions include:. Less common symptoms of endometriosis include spotting between periods, digestive problems, and infertility.

Endometriosis typically is treated with extended-cycle hormonal birth control or an intrauterine device IUD , though some women respond to complementary and alternative therapies such as acupuncture , chiropractic care, or supplements.

The condition often goes away after menopause. Uterine fibroids are noncancerous tumors that grow in the muscular tissue of the uterus. Fibroids often do not cause symptoms or require treatment. For some women, however, uterine fibroids lead to heavy periods or pain , symptoms typically treated with over-the-counter pain relievers containing ibuprofen or acetaminophen or hormonal contraception.

In severe cases, surgery such as endometrial ablation , myomectomy, or uterine fibroid embolization may be required. Polyps are fingerlike growths that attach to the wall of the uterus.

They can range in size from as small as a sesame seed to larger than a golf ball. Many women have polyps without knowing it. When symptoms do occur, they can include irregular periods, heavy bleeding, breakthrough bleeding , and infertility. Uterine polyps carry a small risk of cancer and should be removed with a procedure known as hysteroscopy. Sometimes a dilation and curettage D and C is done to remove and biopsy endometrial polyps.

Some women have a retroverted or retroflexed uterus, which means it is in a tipped or tilted position. This anatomical anomaly usually isn't detected unless a woman becomes pregnant, and usually is not an issue.

However, some women with a tilted uterus may have a higher risk of miscarriage or experience a pregnancy complication known as uterine incarceration. If that happens, a Caesarean delivery will be necessary. There are two types of cancers that can affect the uterus: One, uterine sarcoma, is very rare. The other, endometrial cancer , originates in the endometrial lining and is fairly common.

It typically occurs after menopause. The primary symptom of endometrial cancer is abnormal vaginal bleeding, which may start as a watery, blood-streaked flow that gradually contains more blood. Abnormal vaginal bleeding is not a normal part of menopause and should be discussed with a gynecologist. Tests involving the uterus are used to screen for cancer, diagnose certain diseases and conditions, aid in fertility treatments, and monitor the progress of a pregancy.

They include:. The uterus is usually the size of an apple but can stretch to the size of a watermelon during pregnancy. There are some conditions that may cause an enlarged uterus such as cancer, fibroids, and polycystic ovary syndrome. Sometimes the pelvic muscles and ligaments become weak over time as women age. When these tissues are weak, the uterus is able to drop down into the vaginal area and sometimes pushes out of the vagina.

This is a prolapsed uterus. Risk factors for uterine prolapse include age, having given birth via vaginal delivery, going through menopause, being White, being overweight, and smoking. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Anatomy, abdomen and pelvis, uterus. In: StatPearls [Internet]. Menu Contact Dictionary Search.

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