Search

Abstract: Background: Clinical and experimental researches have linked smoking to disturbances of coagulation and fibrinolysis. Several potential mechanisms are incriminated involving inflammation, fibrinogen synthesis and clotting factors. Based on the fact that the majority of tobacco components cross the placental barrier, the objective of our current study is to investigate the influence of smoking during pregnancy on neonatal haemostasis. Study design: The study was based on a comparative evaluation of coagulation and fibronolysis between healthy full term infants of women who smoked during pregnancy and a control group. Subjects consisted of 39 newborns of smoking and 43 newborns of nonsmoking mothers. Blood samples were obtained shortly after birth and before the administration of vitamin K. Investigation included: PT, INR, aPTT, fibrinogen, coagulation factors II, V, VII, VIII, IX, X, XI, XII, vWillebrand (vWF), protein C and S, APCr, anti-thrombin (AT), t-PA and PAI-1. The independent t- test was used to compare the differences between the values of coagulation and fibrinolytic parameters at the p<0.05 level. Results: We discovered a statistically significant decrease in factor II and protein S levels and an elevation in t-PA and factor VIII concentrations in newborns of smoking mothers, without clinical manifestations of altered haemostasis. There were no significant differentiations in other coagulation or fibrinolytic parameters. Conclusion: The alteration in factor II, protein S, t-PA and factor VIII in neonates exposed in utero to tobacco smoke is not accompanied by loss in the balance between coagulation and fibrinolytic pathways. [Copyright &y& Elsevier]

Abstract: Background: Small for Gestational Age (SGA) neonates often appear with haemostatic alterations, principally due to hepatic dysfunction that results from chronic intrauterine hypoxia. Polycythaemia and thrombocytopenia are common findings in this neonatal population. Study design: We performed a comparison of coagulation, natural inhibitors and fibrinolysis between SGA and Appropriate for Gestational Age (AGA) infants born full term [gestational age (G.A.) >37 weeks]. Study population consisted of 188 healthy newborns, 90 of whom were SGA (62 females and 28 males), while the rest were the control group (44 females and 54 males). Blood samples were obtained within 30 minutes following birth and before the administration of vitamin K. Investigation included: PT, INR, APTT, fibrinogen, coagulation factors II, V, VII, VIII, IX, X, XI, XII, vWillebrand factor, protein C and free protein S, antithrombin (AT), APCR, tPA and PAI-1. The independent t-test was used to compare the differences between the values of haemostatic parameters. Results: Statistical analysis revealed a significant prolongation in PT, INR, elevated levels of tPA (p <0.015, 0.01 and 0.002 respectively) and a decrease in the values of XII and free protein S (p <0.045 and 0.007 respectively) in SGA full term neonates. The two groups had similar demographic characteristics (except birth weight), without significant differences in the values of other haemostatic parameters. Conclusions: Despite of statistically significant differences in PT, INR, values of tPA, XII and free protein S, levels of haemostatic factors range within laboratory references for healthy full term newborns. These findings were not accompanied with clinical manifestations of altered haemostasis. [Copyright &y& Elsevier]