ABSTRACT
This chapter discusses how uterine fibroids interact with the endometrium and how these interactions lead to clinical symptoms. Fibroids are hormonally responsive tumors and are sensitive to both progesterone and estrogen. 17β-Estradiol is associated with increased proliferation of uterine fibroid smooth muscle cells. The relationship between uterine fibroids and infertility is largely dependent on the location of the fibroid, with submucosal and intramural fibroids having the most dramatic impact. The effects of fibroids on implantation and heavy menstrual bleeding were thought to be due primarily to their size and mass. The endometrial stroma in women with fibroids and heavy menstrual bleeding is characterized by dilated endometrial stroma venous spaces compared with normal controls, thereby supporting a decrease in vasoconstrictive factors. Women with uterine fibroids and heavy menstrual bleeding also experience dysmenorrhea. The endometrium of women with uterine fibroids and dysmenorrhea has a high density of endometrial pain fibers in the functional layer of the endometrium.
