Antibodies against phospholipids (PLa) are often thought to be associated w
ith the development of activated protein C (APC) resistance. In the present
study, PLa were followed throughout 29 healthy pregnancies and compared to
APC resistance. The level of PLa did not change during pregnancy [6.9 +/-
3.7 GPL week 12 versus 6.3 +/- 2.8 GPL week 37; 3.3 +/- 1.8 MPL versus 3.2
+/- 1.5 MPL; and lupus anticoagulant (LA) coefficient 0.99 +/- 0.11 versus
0.94 +/- 0.09], in contrast to the APC resistance, which was suppressed (0.
96 +/- 0.22 versus 0.78 +/- 0.13, P < 0.05), but both parameters elevated a
fter delivery (up to 8.7 +/- 4.2 GPL; 1.13 +/- 0.1 LA coefficient; 1.11 +/-
0.22 nAPC ratio; P < 0.05), Three women possessed PLa (1 CLa IgG + IgM; 1
IgG CLa + PSa + PEa; 1 PSa), no LA activity was registered. In the PLa-posi
tive women, dynamics of the nAPC ratio during pregnancy was not related to
PLa.