EN
Morphochemical tests of placentae and clinical examinations of babies born-at-term with intrauterine hypotrophy and of normal body weight were conducted. A decreased activity of cytochrome c oxidase in syncytiotrophoblast, cytotrophoblast extravillous, amniotic epithelium as well as in decidual cells was observed. In all placenta samples we found a diminished percentage of intesvillous space, disordered maturing of villi, lower epithelial plates and striking loss of cytochrome c oxidase activity. It was concluded that diminished metabolic efficiency of placentae is the decisivee risk factor for hypotrophy in chemically polluted areas.