Effect of cigarette smoking on vascular flows in pregnancies complicated by intrauterine growth restriction

• Cotinine causes contraction of the umbilical arteries and the increase of their PI.
• Correlation between cotinine concentration and cerebral–umbilical indices worsening.
• Correlation between cadmium concentration and cerebral–umbilical indices worsening.
• Correlation between exposure to smoke and worsening of flow in fetal ductus venosus.
• Detoxification using metallothionein is ineffective after overexposure to tobacco smoke.

Exposure to tobacco smoke during pregnancy may result in intrauterine growth restriction (IUGR). In the study, the effect of tobacco smoke on vascular flows in the middle cerebral artery, umbilical artery, ductus venosus in fetuses and uterine artery in pregnancies complicated by IUGR was investigated.The study subjects were divided into three groups: smoking women with IUGR (n = 31), women with idiopathic IUGR (n = 28) and healthy controls (n = 50). Fetal biometry and flow parameters were measured. Concentration of heavy metals and antioxidants was tested in maternal blood and fetal umbilical cord blood. The Student t test and multiple regression analysis were used.Cotinine and cadmium concentrations were significantly higher in smokers (55.23 ± 54.23, 1.52 ± 0.9), while metallothionein was significantly higher (22.94 ± 8.64) in the idiopathic IUGR group. Strong correlations between cotinine and cadmium concentrations and cerebral–umbilical index were found.Long-term exposure to tobacco smoke deteriorates flows in vital fetal vessels.