Endometrial Sampling

Endometrial Sampling: What is it and why is it performed?

The endometrium is the inner lining of the uterus. It is a highly specialized and dynamic tissue that changes in thickness and composition throughout the menstrual cycle in response to hormonal signals.

Its main function is to provide a suitable environment for the implantation of a fertilized egg, signifying the start of pregnancy. If implantation does not occur, the endometrium is shed during menstruation, making way for a new endometrium to take its place later on.

The endometrium plays a critical role in female fertility, and its proper development and function are necessary for successful conception and healthy pregnancy. Certain conditions can cause abnormalities in the endometrium, such as endometrial hyperplasia (irregular thickening) – this is a precancerous condition that can lead to endometrial or uterine (womb) cancer if not detected and treated early. This is why some people might need to undergo endometrial sampling and biopsy. Let’s take a closer look at what this process does, why it is needed, and what it entails.

What is endometrial sampling?

 Endometrial sampling, also known as endometrial biopsy, is a diagnostic procedure which extracts small pieces of tissue from the womb lining for examination in the laboratory. The samples are checked for possible infection, abnormal cells, polyps, fibroids, precancerous or cancerous changes.

When do I need an endometrial biopsy?

 Endometrial biopsy is most frequently used when evaluating abnormal uterine bleeding. Patterns of bleeding that require investigation can include:

• Heavy flow or prolonged menstrual bleeding lasting more than 8 days
• Frequent periods occurring more than once a month
• Bleeding or spotting in between monthly periods
• Any bleeding that happens after menopause

 Endometrial biopsies are also useful in evaluating abnormalities in instances when a thickened endometrium is seen on pelvic ultrasound, or when a pap smear test shows endometrial cells present.

This procedure can be done at anytime during the menstrual cycle but pregnancy is a strict contradiction. 

Why is endometrial biopsy important?

 Abnormal uterine bleeding should be taken seriously and investigated to rule out precancerous endometrial hyperplasia or uterine cancer, before any treatment to regulate periods can start.  Investigations can include a pregnancy test, blood tests, STI testing, a pap smear and/or a pelvic ultrasound. However, a full work up should also include an endometrial biopsy to exclude any endometrial abnormalities, especially if the above tests are negative.

Endometrial hyperplasia is a precancerous condition that can eventually lead to uterine cancer. Risks of progression to cancer range from 5-25%, depending on the level of hyperplasia found. Any such hyperplasia, when detected early, can be treated with either oral hormones or an IUD (intrauterine device) with progesterone – this can lead to a regression of the condition in as little as 6 months from the start of therapy.

An endometrial biopsy should be considered for women with the following risk factors for endometrial cancer:

– Aged above 35 years old

– BMI above 30kg/m2

– No children

– Has a history of polycystic ovary syndrome (PCOS)

What happens during an endometrial biopsy?

An endometrial biopsy can be performed in the clinic and does not require anaesthesia. During the procedure, a speculum is inserted so the cervix is visible. A very thin suction tube called a pipelle is then inserted through the cervix, into the uterus, to collect the endometrial sample. This may be repeated up to 3 times to ensure adequate tissue collection and that multiple areas of the endometrium have been sampled. The procedure takes about 10 minutes to complete. The sample is then sent to a laboratory for analysis.

 During and after the procedure, you may experience some mild period-like cramping and discomfort. This should not last for more than a day. You can take paracetamol to help with the discomfort. Some spotting or light bleeding is normal after the procedure for a few days. The procedure is very safe, with less than a 0.1% risk of perforation of the uterine wall.

 In summary, abnormal uterine bleeding should always be investigated to rule out precancerous and cancerous changes of the uterus. Endometrial sampling is a safe and quick procedure that can be performed in clinic, and avoid the risks of general anaesthesia. Early detection can lead to better outcomes, if treatment is started early.

 Speak to us at DTAP @Robertson if you are concerned about abnormal uterine bleeding.