A method of reducing side effects resulting from treatment of a human female with analogs or antagonists of gonadotropin-releasing hormone, said method comprising, during, after or during and after said treatment with said analogs or said antagonists of said gonadotropin-releasing hormone, administering to said human female an effective amount of estra 1,3,5(10)-triene-3,17β-diol-17-valerate, said effective amount being effective to reduce said side effects resulting from said treatment of said human female with said analogs or said antagonists.