Influence of estrogens on serum free fatty acid levels in women.

A relationship between plasma levels of FFA and incidence of hormone-dependent breast cancer has been suggested. This observation has drawn our attention to possible complementary actions of ovarian steroids on circulating FFA levels. Measurements taken in normal women during the menstrual cycle and in ovariectomized women with and without estrogen replacement therapy demonstrate that 1) levels of FFA present in serum are lower during the luteal phase than during the follicular phase; 2) levels of FFA are significantly higher after ovariectomy; and 3) these are again reduced by substitutive estrogen therapy.