Title: Covey DF, et al. Enzyme-generated intermediates derived from 4-androstene-3,6,17-trione and 1,4,6-androstatriene-3,17-dione cause a time-dependent decrease in human placental aromatase activity. Endocrinology. 1981 Apr;108(4):1597-9.
Title: Brodie AM, et al. Antifertility effects of an aromatase inhibitor, 1,4,6-androstatriene-3, 17-dione. Endocrinology. 1979 Jan;104(1):118-21.