Seventy years will elapse next year since the isolation of progesterone. This fact can be considered as a principal stimulus to further investigation of steroids.
The concept of combined progesterone ? estrogen hormonal contraception was born in the fifties of the past century. While the estrogen component of pill has changed little over the years and ethinylestradiol is a good standard, the gestagen component undergoes diversified development that has recently become a hit in specialized media.