- Use of oral contraceptives or other hormonal supplementation such as estrogen. Although early studies suggested no effects on menstrual cycle, alterations in downstream metabolites of pregnenolone (such as estradiol) could theoretically impact the efficacy of oral contraceptives and/or estrogen replacement. Similarly, it is theoretically possible that pregnenolone could be metabolized to other steroids, resulting in hair, skin, or other steroid-related changes. Since we have determined in our prior study that pregnenolone administration does not result in downstream elevations in DHEA, DHEAS, estradiol, or testosterone, these possibilities may be unlikely;