mean baseline progesterone increased from 27.6 +/- 3.2 ng/ml in the first trimester to 41.9 +/- 6.6 in the second trimester ( p less than 0.01 ) and 109.3 +/- 11.2 ng/ml in the third trimester ( p less than 0.001 ) of pregnancy .
C0032979
first trimester
C0032961
pregnancy