Hemostasis in newborns of smoking and nonsmoking mothers.

OBJECTIVE: Our purpose was to determine the effect of smoking during pregnancy on neonatal hemostasis. STUDY DESIGN: Venous blood samples of 26 newborns of smoking and 25 newborns of nonsmoking mothers were obtained from the clamped umbilical cord immediately after birth. Prothrombin fragment 1+2, thrombin-antithrombin III complex, plasmin-alpha2-antiplasmin complex, and D-dimer levels were determined to assess activation of coagulation and fibrinolysis. Cotinine was measured in all neonates to objectify cigarette smoke exposure. The Mann-Whitney U test was used to compare the differences between the values of the parameters of coagulation and fibrinolysis in the two groups at the p < 0.05 level. RESULTS: The median values of prothrombin fragment 1+2 and thrombin-antithrombin III complex in newborns exposed to tobacco smoke in utero did not differ from values of newborns who were not exposed. Nor were the markers of fibrinolysis, plasmin-alpha2-antiplasmin complex and D-dimer levels, influenced by tobacco smoke exposure. CONCLUSION: The balance between the components of coagulation and fibrinolytic pathways in neonates is not disturbed by maternal smoking.

Coagulation and fibrinolysis in smoking and nonsmoking pregnant women.

OBJECTIVES: To assess the effects of smoking during pregnancy on coagulation and fibrinolysis. DESIGN: A cross-sectional study. SETTING: A teaching hospital in Heerlen, The Netherlands. RESULTS: Parameters of coagulation activation increased significantly with gestational age. The values presented are median values. Prothrombin fragment 1 + 2 increased from 0.8 to 2.5 nmol/l in the nonsmoking group of pregnant women and from 1.0 to 1.8 nmol/l in the smoking group. Thrombin-antithrombin III (TAT) levels increased from 2.2 to 9.9 micrograms/l in the nonsmoking group and from 3.1 to 8.5 micrograms/l in the smoking group. Parameters of fibrinolysis showed a different picture. Plasminogen levels in both groups rose significantly in the first half of gestation reaching a plateau in the second half. The alpha 2-antiplasmin levels remained constant in both groups, although the smokers started with significantly higher levels: 119 versus 105% in the nonsmokers. The D-dimer levels rose significantly in both groups: from 278 to 847 micrograms/ml in the nonsmokers and from 215 to 520 micrograms/ml in the smokers. They were significantly lower in the smoking group from the 11th up to the 40th weeks. The D-dimer/TAT ratio was significantly higher in the nonsmokers. CONCLUSIONS: In smoking pregnant women the activated coagulation process was not counter balanced by an adequate increase of fibrinolysis which was the case in the nonsmokers.

Cotinine concentrations in plasma of smoking pregnant women and their infants.

In the Netherlands 30% of all women of reproductive age are habitual smokers. One third of these women continue to smoke during pregnancy. Tobacco smoke consists of more than 3600 different compounds. One of its chief pharmacologically active ingredients is nicotine of which 60% is metabolized to cotinine. Cotinine is the best available biochemical marker of nicotine consumption because it is specific for tobacco smoke exposure and it has a relatively long mean t1/2 of 15 hours. In the present study nicotine and cotinine concentrations were measured in 25 smoking and 25 non-smoking healthy pregnant women. In all 25 non-smoking pregnant women nicotine and cotinine levels were < 10 mg/l. Light smokers (< 10 cigarettes/day) were found to have nicotine blood concentrations < 10 mg/l and cotinine levels varying between 40 and 99 mg/l. Heavy smokers (> or = 10 cigarettes/day) had nicotine concentrations < 10 mg/l, but high cotinine levels varying from 115 to 199 mg/l. Cotinine was also determined in 25 neonates of non-smoking mothers and in 34 neonates of smoking mothers. In 9 of these 34 newborns the relationship between maternal and neonatal cotinine concentrations was investigated. Cotinine levels in neonates born to non-smokers and to women who smoked less than 10 cigarettes/day were below the detection limit of 10 mg/l. Cotinine values in neonates whose mothers smoked > or = 10 cigarettes/day were significantly higher than in those whose mothers smoked < 10 cigarettes/day, but significantly lower than in their mothers. The results of this study confirm that cotinine is more useful than nicotine in discriminating non-smokers, light and heavy smokers. Cotinine concentrations were significantly lower in the neonates than in their mothers, but there was a strong positive linear relationship between maternal and neonatal cotinine concentrations.

Hematological variables in cord blood of neonates of smoking and nonsmoking mothers.

Smoking during pregnancy is associated with maternal and fetal complications. In the present study the effect of maternal smoking on neonatal cellular blood components was investigated. The values of whole blood cell count, leukocyte differential count, and thrombocyte and reticulocyte counts were determined and compared in cord blood of neonates of nonsmoking (n = 89) and smoking (n = 53) mothers. The variables of the erythrocyte and thrombocyte count were not different in cord blood of neonates who were exposed to smoke and in those who were not. In the reticulocyte range the reticulocyte count was significantly lower in the smoking group, while the reticulocyte subsets remained stable. The neutrophils were significantly lower in cord blood of neonates of smoking mothers (p < 0.05). The latter finding might be an explanation for the enhanced incidence of postnatal infection seen in children of smoking mothers.

The reticulocyte count and its subfractions in smoking and non-smoking pregnant women.

UNLABELLED: Our objective was to compare the reticulocyte count and its subfractions in smoking and non-smoking women at different stages of normal pregnancy. STUDY DESIGN: In 247 non-smoking and 123 smoking healthy pregnant women the reticulocyte count and its subfractions were compared at four different stages of pregnancy: 0-10, 11-20, 21-30 and 31-40 weeks. Exclusion criteria were a diastolic blood pressure > or = 90 mmHg, an endocrine disease or a coagulation disorder. Women in the smokers group smoked more than 4 cigarettes a day. Non-smokers were defined as women reporting no smoking at all. Blood samples were run on the Sysmex R-3000 reticulocyte counter. RESULTS: The absolute reticulocyte count was lower in the smoking group throughout pregnancy, but this was only significant in the last ten weeks of gestation (71.9 x 10(9)/l versus 78.8 x 10(9)/l). There was no difference between the low fluorescence, the medium fluorescence and the high fluorescence proportions in the non-smoking and the smoking group. Both groups behaved similarly during pregnancy; there was a decrease of mature reticulocytes and a significant increase of more immature reticulocytes. CONCLUSION: These data show a moderate measurable effect of cigarette smoking on the reticulocyte count and the absence of an effect on the reticulocyte subsets.

Platelet count and platelet indices at various stages of normal pregnancy in smoking and non-smoking women.

UNLABELLED: Our objective was to compare the platelet count and platelet indices of smoking and non-smoking women at different stages of normal pregnancy. STUDY DESIGN: In 247 non-smoking and 123 smoking healthy pregnant women the platelet count, the mean platelet volume, the platelet distribution width and the plateletcrit were compared at 0-10, 11-20, 21-30 and 31-40 weeks of pregnancy. Exclusion criteria were a diastolic pressure > or = 90 mmHg, an endocrine disease, a coagulation disorder, acetylsalicylic acid or phenprocoumon use. A women was considered a smoker if she smoked more than 4 cigarettes a day. Non-smokers were defined as women reporting no smoking at all. Blood samples were run on the Sysmex NE-8000. RESULTS: There was no significant difference between the platelet count in the two groups. In the non-smoking group, the platelet count showed a significant decrease with gestational age (287 x 10(9)/l to 258 x 10(9)/l). This was not the case in the smokers group. The mean platelet volume of the smokers was significantly lower than that of the non-smokers in the last ten weeks of pregnancy (10.4 fl versus 10.7 fl). The platelet distribution width and the plateletcrit did not change under the influence of cigarette smoking. CONCLUSION: Smoking during pregnancy does not significantly affect platelet count or platelet indices.

Cord blood cells and indices: smoking-related differences between the sexes.

The values of whole blood cell count, leucocyte differential, and platelet and reticulocyte counts were determined in cord blood of both male (n = 64) and female (n = 75) newborns of 87 non-smoking and 52 smoking mothers. Leucocytes and neutrophils in cord blood from the male newborns of smokers were significantly lower than those in their female counterparts and in male newborns of non-smokers. These results suggest that male newborns are more affected by cigarette exposure than females with regard to some haematological parameters.

Erythrocyte count and indices during normal pregnancy of non-smoking and smoking women.

OBJECTIVE: To compare the erythrocyte count and the erythrocyte indices of smoking and non-smoking women at different stages of normal gestation. STUDY DESIGN: In 247 non-smoking and 123 smoking healthy pregnant women the erythrocyte count and indices were compared at four different stages of pregnancy: 0-10, 10-20, 21-30 and 31-40 weeks. Exclusion criteria were a diastolic pressure > or = 90 mmHg, an endocrine disease or a coagulation disorder. A woman was considered a smoker if she smoked 4 or more cigarettes/day. Blood samples were run on the Sysmex NE-8000. RESULTS: The erythrocyte count was significantly lower in smokers than in non-smokers (3.86 T/l versus 3.96 T/l in the last 10 weeks). Comparing the erythrocyte count during the beginning and the end of pregnancy there were significant lower values in both groups (4.32 T/l to 3.96 T/l in the non-smoking and 4.24 T/l to 3.86 T/l in the smoking group). The differences in the median Hb and Ht levels were neglectable. The MCV was significantly higher in women who smoked, as was the MCH (MCV 91 fl and MCH 1.90 fmol in the non-smoking versus MCV 94 fl and MCH 1.95 fmol in the smoking group in the last 10 weeks). CONCLUSION: Smoking in pregnancy leads to a lower erythrocyte count and a higher MCV which might create a hypoxic condition of the fetus.

Leucocyte count and leucocyte differential in smoking and non-smoking females during pregnancy.

The total leucocyte count was studied in 194 smoking and 518 non-smoking healthy pregnant women. Smoking in pregnancy appeared to have an additive enhancing effect on the already known total leucocyte increase in pregnancy. The leucocyte differential in 105 smoking and 288 non-smoking pregnant women showed that the eosinophil and basophil count was not involved in the white blood cell shift. The rise of the total leucocyte count was mainly due to an increase of neutrophils, monocytes and lymphocytes. The leucocytosis in the smoking pregnant women was dose-related: significant upward jumps of the percentages of leucocytosis were observed between 12 and 15 cigarettes/day as well as between 19 and 20 cigarettes/day. Further investigation as to the relevance of these observations for pregnancy and fetal well being has to be conducted.