Although the exact cause of fibroids is unknown, several risk factors for fibroids are recognized.

  • Race is an important risk factor. African American women are at two times greater risk for developing fibroids than their Caucasian counterparts. They also are more likely to develop the disease at an earlier age and are disproportionately affected by more multiple and larger fibroids.
  • Overweighed or obese woman are at a slightly higher risk. This may be due to extragonadal estrogens, which are stored in body fat. Women with occult obesity and upper body fat distribution are particularly at risk.
  • Pregnancy and parity appear to be protective which is due to postpartum tissue remodeling during uterine involution, which eliminated small fibroids.
  • With regard to the use of oral contraceptive, studies suggest that combined pills do not increase the growth of uterine fibroids and may in fact decrease the bleeding and dysmenorrhea associated with fibroids.
  • Environmental factors may play a role in the risk of fibroids development. Excessive consumption of red meat increases risk. However, there is no evidence that nutritional adjustments or changes in lifestyle result in relief of fibroid size or symptoms.