the conversions of [ 3h ] pregnenolone ( p5 ) to [ 3h ] progesterone ( p4 ) and [ 3h ] 20 alpha-hydroxypregn-4-en-3-one ( 20-ohp4 ) were determined in vitro in ovaries of 3 ( young ) - and 11 ( aged ) -month-old rats throughout pregnancy .
C0033308
progesterone
C0032961
pregnancy