Effects of Smoking on Uteroplacental Blood Flow

Abstract

The effects of nicotine consumption on uteroplacental blood flow were studied in 20 pregnant women by means of placental blood flow measurements using indium-113m-transferrin. Smokers were found to have a higher rate of poor perfusion patterns than subjects of a control group. In addition, the number of cigarettes smoked daily was significantly correlated with the placental perfusion type. The mean birth weight of infants born by smokers was 250 g lower than in the control group. The results suggest that smoking during pregnancy may compromise uteroplacental blood flow and thus result in poor fetal development.

Morphological Changes in the Placentas of Smoking Mothers: A Histomorphometric Study

“…Therefore, despite the fact that the pla centa can suffer some degree of injury in cig arette smokers, the quantitative morphologi cal analyses of the present investigation are more in favor of the hypothesis which sug gests that the perinatal morbidity associated with cigarette smoking during pregnancy is probably more related to the ischemic and/or toxic effects of several compounds in tobacco smoke, partly on placental function [5,15,16] and also directly on the fetus [4], than to significant alterations in the func tional structure of the placenta. However, the preliminary findings of this study point to the need for more biochemical and physi ological investigations, as well as further morphometric placental studies, especially in cases associated with fetal growth retarda tion, in order to clarify these questions.…”

“…For example, there is strong evi dence that there is an ischemic effect of nico tine on the placenta, which is presumably mediated by its ability to produce vasocon striction of the uterine vasculature [5]. It is also highly probable that placental damage could be due to any one of the several thou sand chemical compounds present in to bacco smoke [13].…”

“…It has been suggested that these adverse ef fects may be caused by toxic substances present in tobacco smoke [4] and/or by alter ations in uteroplacental blood flow [5], It is also possible, however, that these different factors may produce some alterations in the functional structure of the placenta, which in turn could contribute to the fetal morbidity associated with this complication of preg nancy.…”

Review on genetic variants and maternal smoking in the etiology of oral clefts and other birth defects

“…One mechanism by which maternal cigarette smoking may affect embryonic development is through hypoxia, possibly caused by the production of carbon monoxide which interferes with oxygen transfer to the placenta, or nicotine which constricts the uterine wall resulting in hypoxia (Philipp et al, 1984). Experiments in mice also supported the involvement of hypoxia in cleft lip (CL) pathogenesis, in that hypoxia increases the rate of CL in mouse strains with a spontaneous rate of CL while hyperoxia decreases the rate (Millicovsky and Johnston, 1981a, b).…”

Repercussões do tabagismo na ultra-sonografia da placenta e a doplervelocimetria útero-placentária

“…A nicotina provocaria vasoconstricção da circulação uterina por ação simpaticomimética, ocasionando hipoxia transitória e diminuição dos movimentos respiratórios fetais 14 . Como efeito imediato da nicotina, há redução signifi cante no fl uxo da artéria uterina 15 , ocasionando queda do IR de 0,55 para 0,49 16 , o que poderia prejudicar o crescimento fetal 17 . O método radioisótopo permitiu identifi car a diminuição crônica do fl uxo sanguíneo através dos espaços intervilosos placentários nas fumantes 18 , ao passo que a microscopia eletrônica revelou alterações degenerativas do endotélio vascular no cordão umbilical de recém-nascidos de fumantes 19 .…”