Changes of predicted (peptide abundance) of plasmin, kallikrein, and thrombin activity (A) and carboxypeptidase B2 activity (B) in milk from mothers who delivered at an EGA (24–26 wk GA) and LGA (27–32 wk GA) across postnatal ages 2–47 d. Line plots were used to estimate the slopes of EGA and LGA milk samples across postnatal ages (n = 9 per group). EGA and LGA fit represent the line plots for each group, and EGA and LGA obs represent each data point within each group. PGA represents the P value of the effect of GA on the predicted plasmin, kallikrein, and thrombin activity. EGA, early gestational age; GA, gestational age; LGA, late gestational age; obs, observation.