Abstract

The present study aims at assessing morphologic, ultrastructural and chemical changes in placentas from pregnancies complicated with foetal hypotrophy. The following factors were evaluated: changes in macroscopic structure and histological changes in light microscopy. Subsequently, analysis of the chemical composition with a linear distribution of elements was performed by scanning microscopy and X-ray microanalysis. To verify the results, a quantitative determination of selected elements was performed by using atomic absorptive spectrometry.Nine placentas from pregnancies complicated by foetal hypotrophy syndrome were assessed in which infants' birth weight was below 2 500 g and the duration of pregnancy ranged from 38 to 42 weeks. Following weight measurement and macroscopic examination, samples were obtained from the central parts of the placentas and fixed in a formaldehyde solution. Sections for light microscopy were prepared by routine histopathological methods, those for X-ray assessment were analysed using the technique by Grzybek et al.The results of the study showed that, apart from weight differences, no changes were found in the macroscopic structure. Light microscopy displayed a delayed maturation of hypotrophic placentas, hyperaemic chorionic villitis and small haemorrhages in the intervillous spaces.Scanning microscopy and X-ray microanalysis showed an increased level od zinc, copper and iron in micro-areas of the hypotrophic placentas. High heterogeneity was found in the occurrence of the elements in different areas of the same sample. An increased content of the elements may show evidence of a higher activity of antioxidation systems. Zinc may also play a role of a cellular membrane stabiliser. The amounts of elements in the samples were found to be at the detectable limit.The study performed indicates morphologic, chemical and physiological differences in the micro-areas of the same placental sample as well as limitations of the atomic absorption spectroscopy on assessment of the placenta.

Keywords: Placenta, X-ray microanalysis