Estrogens and antiestrogens Three maior naturally occurring oestrogens in women Estradiol (e2) the predominant form in nonpregnant females Estrone(el)produced during menopause Estriol(e3) the primary oestrogen of pregnancyThree major naturally occurring oestrogens in women • Estradiol (E2) the predominant form in nonpregnant females • Estrone (E1) produced during menopause • Estriol (E3) the primary oestrogen of pregnancy Estrogens and antiestrogens