Thrombin, protein C, and protein S values in mother-infant dyads in the postpartum period

Introduction: The objective of the study was to establish the normal range for the levels of antithrombin (AT), protein C (PC), and protein S (PS) in the first week post birth in mother-infant pairings, adjusting for obstetric and perinatal factors, based on 2 different laboratory methods.

Methods: Determinations were carried out in 83 healthy term neonates and their mothers, establishing 3 postpartum age groups: 1-2 days, 3 days, and 4-7 days.

Results: There were no differences in the levels of any of the proteins between the different age groups in neonates or mothers in the first week post birth. The adjusted analysis found no association with obstetric or perinatal factors. The AT and PC levels were higher in mothers compared to infants (P < .001), while the PS levels were similar in both. Overall, the correlation of maternal and infant protein values was poor, except for the levels of free PS in the first 2 days after delivery. Although we found no differences based on which of the 2 laboratory methods was applied, the absolute values did differ.