Fibroids are benign (non-cancerous) growths that most commonly develop in the uterus. According to the Mayo Clinic, as many as three out of four women will develop fibroids at some point in their lives. In most cases, fibroids do not cause any serious medical problems. However, if sharp pains or heavy bleeding during menstruation occurs, it may be recommended by your doctor to have the fibroid removed.
One of the most common causes of fibroids is the presence of excess estrogen. A fibroid is a mass of uterine tissue that occurs when a single cell on the uterus begins to multiply at an excessive rate. Over time, this multiplication results in a microscopic to dangerously large lump, depending on how long the cell multiplies for. Since estrogen is the hormone responsible for developing the lining of the uterus to receive a fetus, the same hormone can cause the uterus cells to grow into a fibroid.
Progesterone can also be a cause for fibroids. Progesterone, like estrogen, is an important hormone that affects the lining of the uterus during conception and fetal development. Like estrogen, progesterone can also cause fibroids to occur by stimulating the cells of the uterine lining to overgrow into a fibroid.
Genetic mutations may also play a role in the formation of fibroids. Cells that form into fibroids often have alterations in them (in comparison to normal cells) that predispose them to grow into fibroids. The cells that make up the lining of the uterus are muscle cells. Like a cancerous cell, one small DNA change in the uterine muscle cell can cause it to grow at an abnormal rate, forming a fibroid. However, unlike cancer cells, a fibroid is benign and does not spread throughout the rest of the body.
Growth Factor Chemicals
Natural chemicals made in the body, such as insulin-like growth factor (IGFs), can also contribute to the growth of fibroids. IGFs are special peptides that promote growth in the body. IGF can also specifically target the muscle cells of the uterus, causing a fibroid to develop.