In the field of female reproduction, the term endometrium is commonly used, but what is it? How does it vary during the menstrual cycle? What is an endometrial biopsy used for? We will answer all these questions below.

What is the endometrium and how does it vary during the menstrual cycle?

The endometrium is the lining of the uterus, that is, the mucous layer that covers the uterus. Throughout the menstrual cycle, this layer undergoes changes depending on hormone levels, such as progesterone and estrogens. At the beginning of the cycle (the first day of menstruation), the concentration of these hormones decreases, causing the loss of the endometrium with menstruation. Subsequently, the lining of the uterus thickens again to reach between 10 and 16 mm and becomes receptive with a trilaminar appearance, which increases the chances of embryo implantation. If conception does not occur (due to an unfertilized egg), the endometrium sheds and the menstrual cycle begins again.

Is the endometrium important for achieving pregnancy?

The endometrium is essential for achieving pregnancy. This is where sperm travel to reach the egg and where the embryo implants.

What is an endometrial biopsy?

An endometrial biopsy is one of the tests recommended for women with implantation failure or abnormal uterine bleeding.
This test involves inserting a thin, flexible tube into the uterus through the cervix. A small sample of endometrial tissue is suctioned and analyzed under a microscope. The results allow for observation of cellular changes that may be related to hormonal concentrations or to observe polyps or fibroids. It also allows for the exclusion of the presence of tumors or endometrial hyperplasia, for example.

Is an endometrial biopsy painful?

This examination usually causes discomfort similar to that of a menstrual cramp. Additionally, sometimes a fine needle is used to inject a local anesthetic into the cervix to reduce pain.

How long does the procedure take and how long do the results last?

The endometrial biopsy usually takes less than 5 minutes, and the results are typically available 1 or 2 weeks later.

What should you consider after an endometrial biopsy?

It is important not to have sexual relations, use tampons, or introduce other substances into the vagina for 2 to 3 days after the endometrial biopsy.

For comprehensive details about IVF In Vitro Fertilization, please refer to the treatments section.