Estradiol valerate
In addition to single-drug formulations, oral estradiol valerate is available in combination with the progestin dienogest as a combined oral contraceptive and intramuscular estradiol valerate is marketed in combination with the progestins hydroxyprogesterone caproate and norethisterone enantate as combined injectable contraceptives. Intramuscular estradiol valerate has also been marketed in combination with testosterone enantate, but this formulation has been discontinued. The availability of estradiol valerate-containing products varies throughout the world.
Estradiol cyclooctyl acetate
Estradiol cyclooctyl acetate (ECoA), or estradiol 17β-cyclooctylacetate, also known as estra-1,3,5(10)-triene-3,17β-diol 17β-cyclooctylacetate, is a synthetic, steroidal estrogen and an estrogen ester – specifically, the 17β-cyclooctylacetate ester of estradiol – which has been studied for use in hormone replacement therapy for ovariectomized women and as a hormonal contraceptive in combination with a progestin but was never marketed. It has greater oral bioavailability than does micronized estradiol due to absorption via the lymphatic system and hence partial bypassing of first-pass metabolism. It is approximately twice as potent as micronized estradiol orally and has a comparatively reduced impact on liver parameters such as changes in sex hormone-binding globulin production.