Removing and testing tissue from the lining of the uterus (also called the endometrial lining) is a way of checking whether or not a hormonal imbalance could be preventing a woman from becoming pregnant. The method for removing this tissue is called an endometrial biopsy. The word "biopsy" is often associated with a test for cancer, and indeed an endometrial biopsy may detect the presence of cancerous cells - but you shouldn't jump to conclusions if your doctor suggests that you should have this procedure. The test is used even when cancer is not suspected.
Endometrium And Pregnancy
The uterine lining (endometrium) plays a vital role in pregnancy. During the menstrual cycle, the sex hormones, including estrogen and progesterone, rise and fall. The fluctuation of these hormone levels triggers the endometrium to grow thicker and thicker as ovulation approaches. A uterine lining of the correct thickness is essential if an egg which has been fertilized by sperm cells in the fallopian tubes is to implant in the uterine lining and grow into a baby.
Therefore, if the levels of estrogen and progesterone are not correctly balanced, the uterine lining is directly affected. It may not grow enough, or it may even become too thick and create blockages in the reproductive system. An endometrial biopsy can indicate whether these hormones are out of sync. If so, hormone medications are just one method that can be used to correct the problem and help the patient become pregnant.
An endometrial biopsy may be performed under local anesthetic, although certain techniques used to remove the tissue are performed under general anesthetic due to the discomfort they cause. Most women tolerate any discomfort they feel during the process relatively well; however, it may be a good idea to take a painkiller such as ibuprofen in advance. Discuss this with your doctor before the procedure.
The procedure takes place just before menstruation begins - i.e. at the point in your cycle at which the tissue is thickest.
- A speculum will be inserted into the vagina and opened up to provide access to the cervix (the mouth of the uterus).
- A tenaculum will be inserted into the vagina and used to keep the cervix steady while the tissue is being removed. A tenaculum is basically a small pair of forceps.
(At this point, the methods used to remove the small sample of endometrial tissue differ. The tissue is usually taken from the fundus (the top) of the uterus.)
The tissue may be collected as follows:
- Using a soft straw called a pipelle which sucks (aspirates) a sample of tissue.
- Using a technique called dilation and curettage in which a sharp instrument is used to remove the tissue, which is then aspirated into a syringe, or by suction.
- Using a method called vabra aspiration, whereby an electronic suction tool aspirates a small amount of tissue.
- Using another method called jet irrigation, whereby a brush is used to loosen up the tissue, and a water jet is used to wash it out.
The tissue sample is then sent off to a laboratory where it's placed under a microscope in order to check for any abnormalities in its cells. It is also tested for the presence and amount of hormones it contains. If your doctor finds that your levels of estrogen and progesterone indicate that there's a problem with your uterine lining, he will proceed with appropriate treatment.