1. Data AnalysisAll the statistical analyses selleck chemical Trichostatin A were performed with SPSS 17.0 for Windows (SPSS Inc., Chicago, IL).Average results for the nonsmoking and smoking groups were compared by using Mann-Whitney rank sum test, and correlations were evaluated with regression analysis. Data were reported as mean ��SE. Statistically significant differences were defined by P �� .05.3. ResultsThe nonsmoking and smoking mothers had similar average age, number of parities, and duration of gestation, and the neonates from nonsmoking and smoking mothers had similar birth weight and Apgar scores (Table 1). Neonates born from nonsmoking and smoking mothers had similar average umbilical cord blood gas values, but neonates born from smoking mothers had significantly greater cord serum erythropoietin levels than nonsmoking mothers (Table 1).

A positive correlation was noted between cord erythropoietin level and average daily consumption of cigarettes (r, 0.58; P �� .05); no correlation was observed between erythropoietin level and average duration of smoking during pregnancy (r, ?0.03; NS).4. DiscussionThe finding of elevated cord erythropoietin levels in neonates born from smoking mothers (Table 1) is consistent with the hypothesis that maternal smoking may cause fetal hypoxia and potential fetal complications [1, 2, 4, 5]. We think that normal arterial oxygen values are because of the compansatuar effect of the erythropoietin.In 3 recent studies, the correlation between fetal hypoxia and umbilical cord erythropoietin levels was well established, but confounding variables were present [2, 12, 13].

In 1 study, neonates that were small for gestational age were included in the smoking mother group [12]. Another study included infants that were small for gestational age, and the effect of growth retardation on erythropoietin levels may have affected the results [13]. In another study with neonates that were small for gestational age, erythropoietin levels were higher in neonates born to mothers with a history of smoking, and the number of cigarettes Brefeldin_A smoked daily was correlated with erythropoietin levels [2]. In the present study, we included neonates that had body weight appropriate for gestational age and who had not been exposed to any adverse events, other than smoking, that may have caused hypoxia. Therefore, our results may reflect the effect of smoking on erythropoietin levels more directly than previous publications.In the present study, the higher erythropoietin levels from neonates born to smoking mothers and the correlation between the amount of cigarette consumption and erythropoietin levels suggest that smoking has a harmful effect in terms of chronic fetal hypoxia and this hazardous effect of smoking is dose dependent.