Levels of antibodies against protein C and protein S in pregnancy and in preeclampsia.

OBJECTIVES: The clinical relevance of antibodies anti-protein C and anti-protein S in pregnancy remains controversial. We evaluate whether, in the absence of thrombophilic diseases, maternal plasma levels of antibodies (IgM and IgG) change during pregnancy and in preeclampsia (PE), with and without superimposed fetal growth restriction (FGR). METHODS: A retrospective cohort of 50 women with PE (n = 30) and PE + FGR (n = 20) and 70 controls [first trimester (n = 20); second trimester (n = 20); third trimester (n = 30)] were enrolled in the study. RESULTS: In healthy pregnant women, plasma levels of anti-protein C antibodies decreased from first to third trimester and were below the range of positivity. IgM anti-protein-C and anti-protein-S were significantly higher (P < 0.001) in both PE (23.88 +/- 10.65 MoM and 43.90 +/- 20.45 MoM, respectively) and PE + FGR group (15.95 +/- 12.62 MoM and 36.02 +/- 27.43 MoM, respectively) than in control group (2.23 +/- 3.23 MoM and 1.68 +/- 4.075 MoM, respectively), in the presence of unchanged levels of IgG isotype. CONCLUSIONS: In this study, we first found that the production of anti-protein C and anti-protein S antibodies decreases throughout healthy pregnancies, while they circulate in high levels in women with PE and PE/FGR.

Increased plasma concentrations of antiprothrombin antibodies in women with recurrent spontaneous abortions.

BACKGROUND: Antiphospholipid antibodies are associated with recurrent fetal loss, but the clinical relevance of antiprothrombin (aPT) antibodies remains controversial. This study was designed to evaluate the relationship of plasma concentrations of aPT antibodies (IgG, IgM, and IgA isotypes) and recurrent spontaneous abortion (RSA) not associated with antiphospholipid-antibody syndrome. METHODS: In this retrospective case-control study, we measured plasma aPT antibodies in 100 pregnant women at 8-12 weeks of gestation who had histories of recurrent abortion not associated with antiphospholipid-antibody syndrome. The controls were 200 healthy gestational-age-matched women with uncomplicated gestations. RESULTS: The mean (SD) plasma aPT concentrations were significantly (P <0.001) higher in women with histories of recurrent abortion than in healthy controls [7.97 (0.79) and 2.08 (0.07) kU/L]. Similarly, the concentrations of IgM aPT were significantly (P <0.001) higher in patients than in controls [5.73 (0.85) and 1.83 (0.05) kU/L]. No differences were found for IgA aPT (P = 0.358). CONCLUSIONS: High concentrations of aPT antibodies (IgG and IgM isotypes) are associated with pregnancy loss in women with RSA. We suggest that the antibodies may have a relevant role in the etiology and pathogenesis of the condition.