Early oral contraceptive history: norethynodrel is not a prohormone.
Edgren
R A
RA
D003276:Contraceptives, Oral; D009641:Norethynodrel / Q000378:metabolism; D011498:Protein Precursors
D003276:Contraceptives, Oral; D011498:Protein Precursors; D009641:Norethynodrel