day 16 blastocysts produced less ( microgram/blastocyst ; p less than 0.01 ) of each prostaglandin than day 19 blastocysts ( pge2 , 0.7 +/- 0.4 vs. 4.2 +/- 1.0 ; pgf2 alpha , 2.1 +/- 0.7 vs. 22.8 +/- 4.1 ; pgfm , 0.03 +/- 0.01 vs. 0.5 +/- 0.2 ) .
C0033554
prostaglandin
C0012472
pge2