Endometrial Hyperplasia

Endometrial Hyperplasia

Endometrial hyperplasia: Overview

Endometrial hyperplasia is an increased growth of the endometrium (the lining of uterus). It is not cancer, but in some cases, it can lead to cancer of the uterus.

Endometrial hyperplasia is proliferation of endometrial glands resulting in a higher gland : stroma ratio. It is most often diagnosed in postmenopausal women, but women at any age with unopposed estrogen from any source are at an increased risk for developing endometrial hyperplasia.

Endometrial hyperplasia is a commonly seen clinical entity. A great majority of patients present with abnormal uterine bleeding. Clinical importance of this pathological entity is the underlying risk of carrying a concomitant genital cancer and the potential risk of progression to endometrial carcinoma during the follow-up. Etiologic evaluation and cause specific treatment is a must for these patients. Treatment of endometrial hyperplasia depends on the patient’s age, fertility desire and the type of present hyperplasia.

Types :

Endometrial hyperplasia  is classified as simple or complex. It also is classified by whether certain cell changes are present or absent. If abnormal changes are present, it is called atypical. The terms are combined to describe the exact kind of hyperplasia:

• Simple hyperplasia

• Complex hyperplasia

• Simple atypical hyperplasia

• Complex atypical hyperplasia

Cytological atypia, which may progress to or co-exist with endometrial cancer and other pathological changes, result from estrogen stimulation unopposed by progesterone. If the hyperplasia is called “atypical,” it has a higher chance of becoming a cancer. Simple atypical hyperplasia turns into cancer in about 8% of cases if it’s not treated. If it’s not treated, complex atypical hyperplasia has a risk of becoming cancerous in up to 29% of cases, and the risk of having an undetected endometrial cancer is even higher.

Hyperplasia without atypia is generally considered benign, with less than 5 percent of cases progressing to cancer.

Risk factors :

Unopposed estrogen either from an endogenous or exogenous source is the most important etiologic factor. Endometrial hyperplasia is more likely to occur in women with the following risk factors:

  • Age older than 35 years
  • White race
  • Never having been pregnant
  • Older age at menopause
  • Early age when menstruation started
  • Personal history of certain conditions, such as diabetes mellitus, polycystic ovary syndrome, gallbladder disease, or thyroid disease
  • Obesity
  • Cigarette smoking
  • Tamoxifen-treated women
  • Family history of ovarian, colon, or uterine cancer
  • Certain conditions may generate unopposed estrogen, including granulosa cell tumors and ovarian thecomas

Signs and Symptoms :

The primary presenting symptom of endometrial neoplasia is abnormal uterine bleeding, which typically prompts an endometrial biopsy to rule out carcinoma. Approximately 70% of women with abnormal uterine bleeding are diagnosed with benign findings and 15% are diagnosed with carcinoma. The remaining 15% receive a diagnosis of endometrial hyperplasia, which includes a broad range of lesions, from mild, reversible proliferations to the immediate precursors of carcinoma.  

If a woman has any of the following, she should see her health care provider:

• Bleeding during the menstrual period that is heavier or lasts longer than usual

• Menstrual cycles that are shorter than 21 days

• Any bleeding after menopause

Evaluation :

Women’s health care provider may perform Transvaginal ultrasound  to measure the thickness of the endometrium.

It should be noted, endometrial thickness varies during the proliferative phase (4–8 mm), whereas the endometrial echo during the secretory phase ranges from 8 mm to 14 mm. Transvaginal ultrasonography is generally not recommended in the virginal patient, and transabdominal imaging is less sensitive and of limited value in the evaluation of the endometrium, but can be used to evaluate other structural abnormalities.

 The only way to tell for certain that cancer is present is to take a tissue sample from the endometrium and study it under a microscope. Women’s health care provider may perform diagnostic tests for endometrial hyperplasia and cancer. This can be done with an endometrial biopsy, dilation and curettage, or a hysteroscopic evaluation of the endometrial cavity and visually directed biopsy for histo-pathological evaluation.


What are the clinical recommendations for the assessment of endometrial thickening when it is found on ultrasound in a postmenopausal patient without bleeding !

Asymptomatic endometrial thickening found on ultrasound examination in postmenopausal women often poses a clinical management dilemma. According to Society of Obstetricians and Gynaecologists of Canada (SOGC) clinical practice guideline ‘Asymptomatic Endometrial Thickening’ (October 2010):

Endometrial sampling in a postmenopausal woman without bleeding should not be routinely performed. 

Indications for tissue sampling of the endometrium in bleeding postmenopausal women with an endometrial thickness of greater than 4 to 5 mm should not be extrapolated to asymptomatic women.

A woman who has endometrial thickening and other positive findings on ultrasound, such as increased vascularity, inhomogeneity of endometrium, particulate fluid, or thickened endometrium over 11 mm, should be referred to a gynaecologist for further investigations. 

Decisions about further investigations should be made on a case-by-case basis in asymptomatic women with increased endometrial thickening and risk factors for endometrial cancer such as obesity, hypertension, and late menopause.