Estradiol (medication)
, estradiol is available in the United States in the following forms:Oral estradiol valerate (Progynova) and other esters of estradiol that are used by injection like estradiol benzoate, estradiol enantate, and estradiol undecylate all are not marketed in the U.S. Polyestradiol phosphate (Estradurin) was marketed in the U.S. previously but is no longer available.
Estriol (medication)
Estetrol (E4), also known as 15α-hydroxyestriol, is a naturally occurring analogue of estriol with an additional hydroxyl group, at the C15α position. It is closely related to estriol and has similar but non-identical pharmacological properties. Like estriol, estetrol is a relatively weak and atypical estrogen. Estetrol is under development for potential clinical use for a variety of indications, such as menopausal hormone therapy and hormonal birth control.https://adisinsight.springer.com/drugs/800034634