SATCHITHANATHAN, S2011-02-142011-02-1419751975SATCHITHANATHAN, S, The Human placenta:morphological variations and norms (in two volumes), University of Sri Lanka (Ceylon) Colombo campus, NSF UC(MED), 1975: Vol.1-1-206, Vol.2-1-123p.http://imsear.searo.who.int/handle/123456789/129783Dissertation: PhD, University of Sri Lanka (Ceylon) Colombo campus, NSF: UC(MED), 1975.AB : The data regarding the morphological features of the human placenta, from Ceylonese subjects has been collected and presented. No prior studies of this nature are available either in this country or in the neighbouring regions. The qualitative and quantitative analysis of maternal, foetal and placental parametera undertaken, establishes norms for these morphological features. The inter-relations between the parameters observed, establishes clinical patterns, about which there have been a certain degree of misconception. Comparison with data obtained through literature, from workers mainly from the European areas, indicates the possibility of a racial, climatic and perhaps a nutritional influence as well. Even though placental weight, volume, surface area, thickness and cord lengths indicate a trend to reduction, statistical analysis, showed no significant differences, in comparison to those of temperate regions. The possibility is that the diversity of the European material was responsible for this lack of significance and perhaps a more detailed study of selected groups both in Europe and in Sri Lanka ( Ceylon ) may add further information to this subject. The normal measures of growth in the placenta, namely its weight, volume, surface area and thickness together with the length of its cord were inter-related to these of the foetus ( its weight and length ) and both measures correlated very highly with only one maternal parameter - the time of growth or the period of gestation. This natural inter-relationship between these parameters generally referred to as measures of normal growth was established here on a factual basis. Certain additional features in the umbilical cord often referred to as " abnormalities " were found to be associated with both live and dead foetuses and there was no evidence to attribute foetal abnormalities and catastrophies to the presence of such " abnormalities " only. The arterial pattern on the placenta was characterised by the presence of Hyrtl's anastomosis, a disperse, magistral or atypical arterial pattern and a dichotomous branching to the level of the tertiary branches. It was established that this vascular catagories and remained uninfluenced by matenal, foetal and placental factors, or by the presence of twists, knots, loops, pathological torsions, localised constrictions, ulcerations and haematomata of the cord. As such the attribution of foetal malformations to deviations of vascular pattern alone was not justifiable. The collective presentation of data and their statistical analysis have been used here to define precisely, widely diverse opinions on maternal, foetal and placental inter-relationshipsen-USUniversity of Sri Lanka (Ceylon) Colombo campus, NSF, UC(MED): Sri Lanka HELLIS NetworkPlacentaPlacenta-anatomy \& histologyThesis