Definition of the Endometrial Stripe

The endometrial stripe is composed of the lining of the uterus (endometrium). When a woman ovulates, the endometrial stripe thickens as the uterus prepares itself for the arrival of a fertilized egg. The stripe allows the right environment for the fetus to grow and become viable. Abnormalities in the endometrial stripe can also indicate the beginning signs of uterine (endometrial) cancer.

Estrogen

• The endometrial stripe is affected by two main hormones: estrogen and progesterone. Estrogen works to grow and expand the endometrium. When the body senses that an egg is about to be released, it produces estrogen. Estrogen causes the endometrium to expand and develop blood vessels. If the released egg is fertilized, the egg can attach itself to the endometrium. The mixture of the thickened lining and the blood vessels allow the egg to continue on in its development cycle toward becoming a fetus.

Decidua

• If a fertilized egg successfully implants itself in the endometrial lining, the stripe will continue to expand with blood vessels, and eventually becomes a decidua. The decidua then connects itself to the placenta and becomes an important part of protection and the nourishment process for the growing fetus.

Menstrual Cycle

• If no fertilized egg arrives, or if the egg is unable to attach itself to the endometrial lining, the newly formed blood vessels and tissue are shed and then excreted through the vagina. This cycle happens about once every 28 days and is called the menstrual cycle. The shedding of the endometrial lining is triggered by the release of the hormone progesterone by the ovaries.

Birth Control

• Many birth control medications, such as DepoProvera, prevent birth by using large doses of synthetic progesterone. While estrogen helps widen the endometrial stripe, the hormone progesterone causes the stripe to remain thin. The thin stripe prevents fertilized eggs from sticking to the endometrial lining and forming into a fetus.

Health Issues

• The most common health issues involving the endometrial stripe are uterine cancer and endometrial hyperplasia. An overly wide and thick endometrial stripe can be an early warning sign for uterine cancer. This can usually be observed through an ultrasound. Endometrial hyperplasia is also caused by the overthickening of the endometrial stripe which can cause heavy and sustained vaginal bleeding. Uterine cancer is usually treated through chemotherapy, while endometrial hyperplasia can be treated through synthetic progesterone treatments.