Summary The effect of steroid therapy on human plasma albumin has been studied. Daily oral ingestion of 5 mg of norethynodrel and 0.75 mg of ethynylestradiol-3-methyl ether depressed albumin levels by 20.9% (p < 0.002). A possible relationship of plasma albumin to the effectiveness of estrogenic therapy in older subjects recovering from a myocardial infarction is noted.