Activated protein C sensitivity, protein C, protein S and coagulation in normal pregnancy.
A prospective study of activated protein C sensitivity, protein C, protein S, and other coagulation factors in 239 women during normal pregnancy was carried out. Protein C activity appeared unaffected by gestation, although an elevation of protein C activity was observed in the early puerperium. A fall in total and free protein S with increasing gestation was observed. Activated protein C sensitivity ratio (APC:SR) showed a progressive fall through pregnancy. This fall correlated with changes in factor VIIIc, factor Vc and protein S. 38% of subjects, with no evidence of Factor V Leiden or anticardiolipin antibodies, showed a low APC:SR (APC:SR <2.6) in the third trimester of pregnancy. Aside from a significant reduction in birth weight, no difference in pregnancy outcome was observed between these subjects and those with a normal APC:SR. Activated protein C sensitivity ratio, modified by pre-dilution of patient samples with factor V depleted plasma, showed no consistent trend with gestation.
Clark
P
P
Department of Haematology, Royal Infirmary, Glasgow, UK.
Brennand
J
J
Conkie
J A
JA
McCall
F
F
Greer
I A
IA
Walker
I D
ID
D001724:Birth Weight; D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests; D001794:Blood Pressure; D001798:Blood Proteins / Q000032:analysis; D003430:Cross-Sectional Studies; D005165:Factor V / Q000235:genetics; D005260:Female; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D049590:Postpartum Period; D011247:Pregnancy / Q000097:blood*; D011256:Pregnancy Outcome; D011264:Pregnancy Trimesters; D011446:Prospective Studies; D011486:Protein C / Q000502:physiology*; D017293:Protein S / Q000502:physiology*; D012016:Reference Values; D012606:Scotland
D001798:Blood Proteins; D011486:Protein C; D017293:Protein S; C095381:factor V Leiden; D005165:Factor V