[The influence of smoking on uteroplacental blood flow and maternal carboxyhemoglobin levels].

The effect of nicotine consumption on uteroplacental blood flow and on the carboxyhemoglobin concentration in maternal serum was examined in 20 pregnant women. It was found that poor uteroplacental circulation is more frequent in women who smoke than in those in whom placental insufficiency is suspected. Normal circulation of Type I was only recorded in gravidae smoking not more than 10 cigarettes a day. Determination of the carboxyhemoglobin concentration in the maternal serum as an indicator of the overall level of contamination by tobacco smoke revealed a significant correlation of the morning value with the placental blood flow type. The average birthweight of the newborns of smokers was 300 g lower than might have been expected. In isolated cases chronic nicotine abuse led to intra-uterine growth retardation, with no other apparent causes of placental insufficiency.