A Quantitative Study on the Effects of Maternal Smoking on Placental Morphology and Cadmium Concentration
Autor: | David Abramovich, M.D. Burke, Terry M. Mayhew, Kenneth Robert Page, Peter G. Bush, P.J. Aggett |
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Rok vydání: | 2000 |
Předmět: |
medicine.medical_specialty
Placenta Fetal Hypoxia Nicotine chemistry.chemical_compound Pregnancy Internal medicine Cytochrome P-450 CYP1A1 medicine Humans Cotinine Fetus business.industry Smoking Case-control study Obstetrics and Gynecology Transplacental Intervillous space medicine.disease medicine.anatomical_structure Endocrinology Reproductive Medicine chemistry Case-Control Studies Female business Cadmium Developmental Biology medicine.drug |
Zdroj: | Placenta. 21:247-256 |
ISSN: | 0143-4004 |
Popis: | The aim of this study was to quantify the effects of maternal cigarette smoking on placental morphology, paying particular attention to variables known to be influential in facilitating oxygen diffusion. Structural quantities were estimated by stereological analyses of placental samples drawn from non-smoking and smoking women whose smoking habits were assessed both subjectively (from volunteered cigarette consumption) and objectively (by determining levels of plasma cotinine, a major metabolite of nicotine). Concentrations of placental cadmium were also measured. In the smoking group, maternal and fetal haematocrits were elevated and mean birthweight was reduced. Within placentae, the most significant alterations were increases in cadmium levels, the relative volumes of maternal intervillous space, the relative surface areas of fetal capillaries and decreases in the relative and absolute volumes of fetal capillaries. Findings indicate that changes in capillary volume are the result of a decrease in mean capillary diameter rather than total length. The mean thickness of the trophoblast component of the villous membrane was also increased in the smoking group. Although increased haematocrits suggest that fetuses of smoking mothers suffer hypoxic stress, these morphological changes are likely to compromise, rather than assist, transplacental oxygen transfer. This is in marked contrast to the adaptive changes seen in pregnancies associated with preplacental hypoxia and suggests that other factors might be compromising the fetoplacental unit. Finally, although the morphological changes associated with maternal smoking seem to be the result of an all-or-none, rather than dose-dependent, effect, the available evidence is not conclusive. |
Databáze: | OpenAIRE |
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