A thickened endometrium, also known as endometrial hyperplasia, is a problem that occurs when the inner lining of the uterus becomes very thick. This lining is what changes when we have our periods and is also the layer that houses the foetus during pregnancy.
Generally, a thick endometrium is caused by a hormonal imbalance between oestrogen and progesterone, the hormones that regulate the menstrual cycle. This imbalance causes lining cells to proliferate excessively. The most common sign of this abnormal growth is vaginal bleeding, and it usually appears in women over the age of 45. Depending on the changes we can observe in the thickened endometrium, the World Health Organisation (WHO) classifies endometrial hyperplasia into four different classes: simple, complex, atypical simple and atypical complex.
In the first two, the endometrial cells are normal in appearance. When we say that a cell is atypical it is because it is more likely to become cancerous. So, the second two have a higher chance of developing uterine cancer. The latter has a 29% chance of developing uterine cancer. For this reason, it is essential not only to have annual gynaecological check-ups but also to seek advice on any alteration in the bleeding, or bleeding that occurs when the menopause has already appeared.
Symptoms of endometrial hyperplasia
As mentioned earlier, the most common symptom of thick endometrium is abnormal menstrual bleeding or bleeding that occurs between periods. Or bleeding that is heavier than usual. Or bleeding that occurs after the menopause. In fact, heavy bleeding can lead to iron deficiency anaemia.
Pelvic pain or dyspareunia (pain during sexual intercourse) may also be a symptom. Many of these symptoms are common in the transition to menopause, which often leads to episodes of irregular bleeding. It is also possible for a woman with a thick endometrium to have no symptoms at all.
Endometrial hyperplasia is usually diagnosed by ultrasound. This can determine whether it is necessary to perform a hysteroscopy (to see the inside of the uterus) and a biopsy, to take samples of the tissue inside the uterus in those areas where there may be alterations.
Risk factors for thick endometrium
Are there any factors that may favour a woman having this problem? It rarely occurs in people under the age of 35, so perimenopause is a factor that increases the likelihood. But there are other risk factors such as:
- Polycystic ovary syndrome
- Endometriosis
- Diabetes or obesity
- Never having been pregnant
- History of breast, ovarian or colon cancer (with tamoxifen treatment or pelvic radiation).
Thickened endometrium in menopause
During menopause the endometrium has to be linear and thin, as the ovaries stop functioning and no longer produce both oestrogen and progesterone. A thickened endometrium in a menopausal woman is always abnormal and should be studied.
Endometrial hyperplasia treatment
Treatment for thick endometrium depends on the type of endometrial hyperplasia. It ranges from hormone therapy (which can be in pill form, with a hormonal IUD or an injectable) to radical surgery in which the uterus is removed if the risk of uterine cancer is very high.
As we will see in more detail below, if it is a benign hyperplasia, we first need to correct the hormonal situation, for example, by means of slimming diets (if the cause is obesity) or with contraceptive pills in the case of women with polycystic ovary disease. This would then be followed by actual hormone treatment. However, if it is endometrial hyperplasia in which there are cellular alterations, it would be assumed to be a pre-cancerous lesion and, in this case, surgery would be considered as the first therapeutic option.
Hormone therapy for thickened endometrium
Some types of thickened endometrium are hormone-sensitive, because they are the result of an imbalance between oestrogen and progesterone, which means that the uterine lining can become overstimulated, and the glandular cells may overgrow and multiply. This therapy is recommended if it turns out that, despite the thickening, there is no endometrial atypia and the cells have a normal structure, so the risk of cancer is low.
In this case, hormone treatment with progestogens is sufficient, and sometimes the changes may even disappear spontaneously, as hormone treatment aims to reduce the level of progesterone and oestrogen in the woman’s body, allowing menstrual bleeding to stop and, consequently, alleviating the symptoms caused by this imbalance.
Radical surgery for thickened endometrium
Endometrial thickening itself is not yet regarded as a disease, but it can lead to endometrial cancer if we are referring to atypical hyperplasia, a much more serious condition. Usually, the diagnosis of this type of hyperplasia is an indication for prophylactic removal of the uterus. Sometimes, however, the disease affects women who intend to give birth to a child. Hormonal treatment is then used, but the woman must be under constant medical supervision.
On the other hand, if the risk of endometrial cancer is present, a biopsy and examination of the mucosal fragment taken under laboratory conditions will then be necessary before resorting to radical surgery. The usual procedure in case of hyperplasia with atypia includes taking an endometrial biopsy and confirming the presence of atypia. In this case, the recommended surgery is total hysterectomy, in other words, resection of the entire uterus.
How does a thickened endometrium affect pregnancy?
Oestrogen and progesterone are responsible for preparing the endometrium to receive the fertilised egg. So, logically, when there is an imbalance of these hormones and an abnormal growth of the endometrium, this can compromise the chances of pregnancy. The endometrium, where the embryo must settle, becomes, in this case, an unfavourable environment for pregnancy to take place. It is therefore advisable to consult a specialist if this type of problem exists.
