compared to control cultures , progesterone ( p < 0.001 ) in physiologic tissue levels of 5 to 20 micrograms/ml , pregnenolone ( p < 0.001 ) , 20 micrograms/ml , and 20 alpha-dihydroprogesterone ( p < 0.001 ) , 20 micrograms/ml , suppressed the secretion of hcg throughout the study period .
C0033308
progesterone
C0012311
20 alpha-dihydroprogesterone