Sulfates are the foremost circulating conjugates of ethinyl estradiol and glucuronides predominate in urine. The main oxidative metabolite is 2-hydroxy ethinyl estradiol, fashioned because of the CYP3A4 isoform of cytochrome P450. Part of the 1st-go metabolism of ethinyl estradiol is believed to arise in gastrointestinal mucosa. Ethinyl estradiol m