What is endometrial hyperplasia?

Endometrial hyperplasia is a gynecological condition associated with hormonal imbalances. It most often occurs in postmenopausal women, but it cannot be completely ruled out in women of reproductive age. Although endometrial hyperplasia itself is not a separate disease, it is one of the main causes of uterine cancer, so it should not be ignored. In this article, I have gathered the most important information about endometrial hyperplasia to draw your attention to its possible consequences. symptoms should prompt you to see a doctor. 

Endometrial hyperplasia – definition

Endometrial hyperplasia is a gynecological condition, but to fully understand it, it's worth starting by explaining what the endometrium is. The endometrium is the mucous membrane lining the inner cavity of the uterus. It plays a crucial role in maintaining a healthy menstrual cycle, as well as pregnancyIt undergoes cyclical changes related to hormonal fluctuations during specific phases of the cycle – for example, it thickens to accommodate and implant an embryo, and if fertilization doesn't occur, it is shed and excreted from the body with menstrual blood. Although it doesn't constitute a separate organ, it is crucial for hormonal and reproductive health. 

So what is endometrial hyperplasia? It is a condition in which morphological changes occur in the endometrial cells.The mucosa becomes excessively thickened, which carries a number of serious consequences. Unfortunately, changes in the endometrium can even predispose to the development of endometrial cancer, so they shouldn't be ignored, whether you're planning a pregnancy or not. 

Endometrial hyperplasia – causes 

The direct and most common cause of endometrial hyperplasia is increased exposure to estrogens combined with a relative deficiency of progesterone. Colloquially, this condition is called estrogen dominance or unbalanced estrogen. Estrogens are essential hormones for women's health, influencing the menstrual cycle, fertility, cardiovascular health, and the health of our bones and joints. However, hormonal balance is paramount, and excess estrogen predisposes to many health problems. 

Where do these hormonal imbalances come from? It's a very complex and multifactorial problem. The most common causes are:

• • Obesity Excess adipose tissue promotes many hormonal disorders, as it is an endocrine-active tissue. Among other things, it leads to increased adrenal activity and the production of androgen precursors (androstenedione), which are converted into estrone and estradiol. Additionally, aromatase activity, the enzyme responsible for the conversion of androstenedione to estrogen, increases. Furthermore, in cases of overweight and obesity, sex hormone-binding globulin (SHBG) levels decrease, which leads to increased estradiol concentrations in the blood. 
  • Diseases causing anovulation (e.g. polycystic ovary syndrome, hyperprolactinemia) Under normal conditions, after ovulation, the corpus luteum forms, which produces progesterone. Chronic anovulation causes estrogen levels to remain high and cannot be balanced by progesterone. 

• Early onset of menarche (before age 12) and late menopause (after age 55).

• Estrogen tumors These are pathological changes arising from the granulosa cells of the ovary, which secrete estrogen and lead to an imbalance between estrogen and progesterone levels. It is estimated that 25-50% of women diagnosed with estrogen-secreting tumors also suffer from endometrial hyperplasia. 
• Some medications Tamoxifen, a selective estrogen receptor modulator (SERM), is used in the endocrine treatment of hormone-dependent breast cancer, but unfortunately, it is associated with an increased risk of developing endometrial hyperplasia in postmenopausal women. This risk is also increased in women taking estrogen medications and hormone replacement therapy. 

Endometrial hyperplasia – symptoms

The most common symptom of endometrial hyperplasia is abnormal vaginal bleeding. They can manifest as very heavy and prolonged periods, during which the body expels not only fresh blood but also clots. Very irregular cycles and spotting between periods are also possible. Women after menopause, when ovarian activity ceases and the menstrual cycle ceases, may experience vaginal bleeding. However, symptoms can sometimes be absent or very subtle, so even if you feel well, survey preventive measures are an important element of health care. 

Endometrial hyperplasia – how to recognize it?

The occurrence of the above symptoms should prompt you to visit a doctor. gynecologistThe specialist will guide you step by step through the diagnostic process. The first step is always a detailed interview – it's worth preparing for this before your appointment. This will ensure you don't miss anything, you'll feel more confident, and you'll be able to provide the doctor with all the information necessary for a correct diagnosis. In addition to a detailed interview, the following tests are also performed to confirm or rule out endometrial hyperplasia: 

• Transvaginal ultrasound In premenopausal women, endometrial thickness varies physiologically depending on the phase of the menstrual cycle. Therefore, this test cannot definitively determine the presence of hyperplasia, but it can help detect conditions such as fibroids or polyps. However, in postmenopausal women, this test becomes more important. It is assumed that an endometrial thickness of ≤4 mm has a >99% negative predictive value for endometrial cancer – this means that with this result, hyperplasia and the risk of cancer can be ruled out with a high degree of probability. 
• Taking samples of the endometrium The most common procedure is an endometrial biopsy, which involves collecting samples by inserting a special tube (Pipelle cannula) into the uterus through the cervix. This biopsy is most often performed in young women experiencing abnormal uterine bleeding, and sometimes also in cases of PCOS and estrogen-producing ovarian tumors. Another, slightly more precise but more invasive method is hysteroscopically guided uterine biopsy. This involves inserting a hysteroscope through the vagina and cervix into the uterine cavity and examining its interior with a camera. If the doctor notices any abnormalities, the biopsy is taken for histological examination. This procedure allows for precise sampling and is performed under general anesthesia.  

Endometrial hyperplasia – how to treat it?

Endometrial hyperplasia can be treated conservatively with progesterone therapy. It involves the oral or intrauterine administration of progestogens. IUDs are the preferred method because they deliver higher local doses of hormones and avoid side effects associated with systemic hormonal effects. They are also easier on the patient – ​​there's no need to remember to take medications. This method is particularly recommended for women who want to maintain their fertility and achieve pregnancy in the future. It is characterized by high effectiveness, reaching up to 89-96%. 

For postmenopausal women and those who are definitely not planning a pregnancy, a doctor may consider a total hysterectomy, or removal of the uterus. This is especially important if the endometrial hyperplasia is advanced and atypical, meaning it significantly increases the risk of developing cancer in the future. 

Endometrial hyperplasia and endometriosis – what are the differences?

Endometrial hyperplasia and endometriosis These are concepts that are often used interchangeably in everyday language, but unfortunately this is a mistake. These are two completely different problems and it is worth being aware of this so that communication between women and women and doctors is effective.So what are the differences? Endometrial hyperplasia is the growth of endometrial cells within the uterine cavity. The endometrium becomes thickened, which promotes excessive bleeding and is primarily due to an imbalance between estrogen and progesterone. Endometriosis, on the other hand, is the presence of endometrial cells outside the uterine cavity, for example, in the intestines or ovaries. It may or may not be accompanied by endometrial hyperplasia. Its causes are much more complex, and it's not always possible to pinpoint a single factor. 

Summary

Endometrial hyperplasia is a disorder characterized by excessive growth of the mucosal lining of the uterine cavity. It primarily manifests as excessive menstrual bleeding and bleeding between periods. The direct cause is an excess of estrogen and a relative deficiency of progesterone, so the primary treatment method involves oral or intrauterine administration of progesterone. Unfortunately, untreated endometrial hyperplasia significantly increases the risk of developing cancer, making preventative testing and consultations crucial if disturbing symptoms occur.

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