A Clinical Comparison of Three Commercial Estrogenic Preparations1

Abstract

The assay of 3 commonly used estrogenic preps.[long dash] a-estradiol benzoate, estrone and diethylstilbestrol[long dash]on a group of postmenopausal women was studied by means of vaginal smear response. Manufacturer''s claims lead the physician to believe that 1.0 mg. of estrone, 0.17 mg. of [alpha]-estradiol benzoate and 0.4 mg. of diethylstilbestrol are equivalent. On the human subject this study showed that 1.0 mg. of estrone (intramusc), 0.42 mg. of [alpha]-estradiol benzoate (intramusc.) and 0.5 mg. of diethylstilbestrol (orally) all produce the same results. Diethylstilbestrol is far cheaper than the other 2 preps. by any method of assay. a-estradiol benzoate costs 1/3 as much as estrone according to manufacturing claims but it is nearly as costly when based on human response. No appreciable difference was noted in promptness or duration of response to dosages of the 3 estrogens, which produced similar smear changes on the 11th day of treatment. The inadequacy of using a unit scale based on rodent response when dealing with human beings is emphasized.