DHEA is transformed into DHEA-S by sulfation at the C3β position via the sulfotransferase enzymes SULT2A1 and to a lesser extent SULT1E1 .    This occurs naturally in the adrenal cortex and during first-pass metabolism in the liver and intestines when exogenous DHEA is administered orally. [ citation needed ] Levels of DHEA-S in circulation are approximately 250 to 300 times those of DHEA.  DHEA-S in turn can be converted back into DHEA in peripheral tissues via steroid sulfatase (STS).  
However, in December 2004 the United States the 14-member Food and Drug Administration (FDA) advisory committee, plus voting consultants, for Reproductive Health Drugs unanimously rejected Procter and Gamble's fast-track request for Intrinsa citing concerns about off-label use . In Canada, post-menopausal women have been able to obtain government-approved testosterone treatment since 2002. In Australia, post-menopausal women can use Organon testosterone implants which have to be surgically inserted and last from three to six months.