Maternal uterine activation - UAP expression. Relative mRNA expression of Fp (A) and Otr (B) in uterus. Data shown are means ± SEM of determinations in duplicate per group (n= 5 each). Means with different letters are significantly different. P values: A) a vs. b p=0.045, b vs. c p=0.05, a vs. c p=0.02; B) a vs. b p=0.0257.