Maternal and fetal platelet activation in normal pregnancy.

Objective: To study the platelet activation phase in normal pregnant women and their fetuses, both in vivo under basal conditions and in vitro after stimulation by adenosine diphosphate (ADP), a weak agonist, and U46619, a strong one. methods: Platelet function was investigated in 39 normal pregnant women and their fetuses undergoing fetal blood sampling at 18-37 weeks' gestation, using flow cytometry and the anti-GMP140 monoclonal antibody. This combined technique allows platelets to be investigated in small aliquots of whole blood, and it detects platelet secretion regardless of aggregation