the estradiol ( e2 ) to estriol ( e3 ) ratio during human pregnancy depends on fetal liver hydroxylation of fetal adrenal dehydroepiandrosterone sulfate ( dheas ) and conversion by the trophoblast of dheas and 16 alpha-hydroxy-dheas ( 16 oh-dheas ) to estrone ( e1 ) , estradiol ( e2 ) , and estriol ( e3 ) , respectively .
C0032961
pregnancy
C0014912
estradiol