What are the probable causes of fibroids?

What are the probable causes of fibroids.jpg

Doctors don’t know what causes fibroids, but there are some researches disclosing some probable factors:   
Genetic alterations. Many fibroids contain alterations in genes that code for uterine muscle cells.  
Hormones. Estrogen and progesterone, two hormones that stimulate development of the uterine lining in preparation for pregnancy, appear to promote the growth of fibroids. Fibroids contain more estrogen and estrogen receptors than do normal uterine muscle cells.
Other chemicals. Substances that help the body maintain tissues, such as insulin-like growth factor, may affect fibroid growth.
Besides, there are some more factors such as obesity, diet and mental issues may cause fibroids.

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