HCG causes stimulation of the P450 Side Chain Cleavage Enzyme. The enzyme is responsible for converting cholesterol into pregnenolone. In vitro studies show that HCG stimulates the activity of this enzyme, which should result in increased pregnenolone levels:Another not-so-well-known potential advantage of HCG is its ability to increase pregnenolone, the "master hormone" that is at the top of our production line. Virtually all of the well-known hormones, many of which help us mentally and sexually, start with pregnenolone, including DHEA, testosterone, estradiol, DHT, progesterone and cortisol.