Estradiol and progesterone regulate the proliferation of human breast epithelial cells.

Authors: Foidart JM, Colin C, Denoo X, Desreux J, Beliard A, Fournier S, de Lignieres B.

Publication Year: 1998

Citation: Fertil Steril 1998;69(5):963-9.

In this double-blind randomized study to evaluate the effects of estrogen and progesterone on normal breast cells, 40 postmenopausal women received daily topical application of a gel containing either placebo, estradiol, progesterone, or estradiol + progesterone for two weeks prior to esthetic breast surgery or the excision of a benign breast lesion. The results showed that increased estrogen concentration increased the number of cycling epithelial cells, whereas exposure to progesterone for 14 days reduced the estrogen-induced proliferation of normal breast epithelial cells.