Elevated first trimester maternal levels of soluble fibrin polymer are associated with lower birthweight in twin gestation.

We assessed soluble fibrin polymer longitudinally in normal pregnancy, thrombophilic pregnancy and twin gestation Thirty-three thrombophilic pregnancies, 34 uncomplicated multiple gestations and 23 singleton normal pregnancies were studied. Maternal plasma samples were collected in the first (6-12 weeks), 2nd (13-25 weeks) and 3rd trimesters of pregnancy (26-40 weeks) and were stored at -70 degrees C until assay. Soluble fibrin polymer was assayed by enzyme-linked immunosorbent assay (ABS, Copiague, New York, USA). Statistical analysis were made by Spearman test and Levine's test for equality of variance (P < 0.05). First soluble fibrin polymer maternal levels in twin gestation were significantly higher than in normal pregnancy and thrombophilic pregnancy, (23.8 +/- 4.5 mug/ml versus 9.2 +/- 3.1 and 10.0 +/- 2.0 mug/ml respectively, P < 0.005). Second and third trimester maternal levels of SFP in twins were also significantly higher than in normal pregnancy. First trimester soluble fibrin polymer was highly correlated with birthweight in twin gestation (r = -1, P < 0.01). In the third trimester, maternal soluble fibrin polymer correlated with placental weight in twin gestation (r = 0.639, P < 0.01). Overall, soluble fibrin polymer was correlated with placental weight and birthweight in the three groups but this did not reach statistical significance. Elevated maternal plasma levels of soluble fibrin polymer in twin gestation may derive from an accelerated coagulation process due to extensive vascular remodelling. Current studies are underway to determine the utility of soluble fibrin polymer in assessing fetal growth abnormalities.