Squamous metaplasia is a process of transformation of the tissue that lines the uterus, which no longer has only one layer with elongated cells, and has several layers. This is a normal and benign process of protection of the body that may occur at certain periods of a woman's life such as puberty or pregnancy, when there is increased vaginal acidity, or when uterine inflammation or irritation occurs, infection with sexually transmitted diseases or use of contraceptives, for example.
Cellular changes are not considered to be dangerous or increase the risk of cervical cancer, however, squamous metaplasia can very rarely cause precancerous cellular changes.
Squamous metaplasia of the cervix does not need treatment, however it is important to consult the doctor regularly to evaluate the evolution of the metaplasia.
Phases of squamous metaplasia
Squamous metaplasia goes through the following phases:
1. Reserve cell hyperplasia
Squamous metaplasia begins in more exposed regions of the cervix, in which small reserve cells are formed, which, as they form and multiply, form a multi-layered tissue.
2. Immature squamous metaplasia
This is a phase of metaplasia in which the reserve cells have not yet finished differentiating and stratifying. It is very important to identify this area and to do regular tests to analyze its evolution, because it is where most of the manifestations of cervical cancer appear.
3. Mature squamous metaplasia
The immature tissue may reach maturity or remain immature. When the immature epithelium converts to mature tissue, which is already fully formed, it becomes more resistant to aggression, with no risk of complications.
Immature squamous metaplasia by HPV
In some cases, the epithelium may remain immature, which is considered abnormal and can initiate cellular changes that can lead to cancer. Although this complication is not very frequent, it can occur in some people due to an HPV infection, which is the human papilloma virus.
HPV can infect these immature squamous cells and turn them into abnormal cells.
Possible causes:
Several factors can lead to squamous metaplasia:
- Increase of vaginal acidity, which is more frequent in the fertile age and in the pregnancy;
- Uterine inflammation or irritation;
- Exposure to chemical substances;
- Excess of estrogen;
- Deficiency in vitamin A;
- Presence of uterine polyps;
- Use of contraceptives.
In addition, squamous metaplasia may also be caused by chronic cervicitis, which is a constant irritation of the cervix, which mainly affects women of childbearing age. See more about this disease.
