Prematurity and growth retardation: different causes of fetal coagulation disorders

prematurity and fetal growth retardation complicates in general one in five pregnancies. The combination of prematurity with severe growth retardation and hypoxia worsens the prognosis due to increase of periventricular hemorrhage incidence, and later coronary heart disease, hypertension, stroke, miscarriage and fetal growth retardation in own pregnancies in adulthood. The causes of impaired blood coagulation and fibrinolysis in retardated and premature newborns remain poorly understood. The goal of the study - to compare the parameters of blood acid-base and gases balance, coagulation and fibrinolysis in prematurity and growth retardation. Material and methods. Newborns of three clinical groups were examined. 24 full-term newborns with a postnatal diagnosis of I-II growth retardation stage constituted group I. 18 newborns of group II were born prematurely, corresponding to pregnancy term of 28-34 weeks. Control group III consisted of 20 full-term healthy infants. The birth took place without emergency interventions and without perinatal losses. Blood samples of the umbilical cord artery were obtained immediately after it was clamped. The parameters of blood acid-base and gas compositionof mothers and newborns blood and the fetal kinetic characteristics of blood coagulation and fibrinolysis were compared. Results. Newborns of group I had a pH of 7.27±0.012, in group II - 7.33±0.022, in group III - 7.30±0.024, which corresponded to the difference between maternal and fetal values of 0.10; 0.07 and 0.13. The pH difference in growth retarded fetuses is higher than in premature fetuses, closely to that of full-term fetuses, despite the lowest pH. Parameters of pO2 and pCO2 in labor do not have an indicative difference in newborns of all groups. Thromboelastometric parameters of the premature infants blood indicate low density and accelerated clot lysis, but while growth retarded fetuses accelerated formation and incomplete clot lysis. That is because of notable predominance of endothelial origin procoagulant factors in growth retarded fetuses. Indicators of acid-base and gas balance in newborns with growth retardation are shifted towards acidosis, in contrast to anthropometrically similar premature infants, whose indicators are higher than full-term fetuses ones.