You were not taking hCG when the lab work for pregnenolone was done? If so, hCG could recover pregnenolone. Pregnenolone is made by mitochondria in your cells. You can improve mitochondrial function with high potency B vitamins, anti-oxidants, fish oil, vit-D3, CoQ10 [ubiquinol type], acetyl-l-carnitine [ALC] and lipoic acid.
In healthy normal males, a lot of pregnenolone is made in the testes. TRT HPTA shutdown can lower pregnenolone levels and as DHEA is made from that, TRT can lower DHEA as well.