The Role of Parity on Some Macroscopical and Microscopical Variables in Placentas of Normal and Preeclamptic Women

INTRODUCTION: Placenta enjoys much attention as an organ of union between mother and fetus. Their histological composition was from fetal portion which consists of the villi of the chorion frondosum and maternal portion which is formed by the decidua basalis containing the intervillous space (1,2) . Placenta nearly provides anaccurate record of intrauterine journey of fetus which may undergo morphological and biological deviation (3,4) , owing to the needs of fetus growth and in response to pathological conditions (5,6) . One such disorder is preeclampsia which is mainly peculiar to human pregnancy and based on a presence of hypertension and proteinuria, occurring after 20 ABSTRACT: BACKGROUND: The placenta is a dynamic organ, throughout gestation, it continuously undergoes different changes in structure and function to support the prenatal life. The anomalies of the placenta are usually associated with pregnancy complicated diseases which could lead to fetal complications. Hence, a careful examination of placenta in-utero as well as post-partum provides much insight into the prenatal health of the baby and the mother and can give information which could be useful in the management of complications in mother and the newborn, especially in a community like ours, where antenatal mothers still come unbooked to the labour room. OBJECTIVE: The aim of the present study was designed to elicit some morphometrical variables of delivered placentas ( both gross and microscopic) in normal and preeclamptic pregnancies with regard to the role of parity (birth order) as a physiological change in women's life that may affect placental morphometrical variables. PATIENTS AND METHODS: A total of twentyfour placentas were freshly collected. They were grouped into two major groups (normal and preeclamptic) and each group was further subdivided according to parity into primi and multi subgroups (6 placentas for each subgroup). The placentas were grossly examined for (shape, insertion of umbilical cord,diameter and central thickness). Then tissue samples were fixed, processed , sectioned and stained by heamatoxylin and eosin stain to study the following microscopical variables as number of (villi, syncytial knots and fetal capillaries) . RESULT: Studying placentas had circular to oval shape. The percentage of central insertion of umbilical cord was increased in control group, mainly in multi one. While marginal insertion was increased mainly in primi preeclamptic. There was a significant reduction in diameter of placentas of preeclamptic group, mainly at primi. The placental thickness was significantly increased in preeclampsia. Statistical analysis for histomorphometrical variables had got an increased in number of villi, syncytial knots and fetal capillaries with preeclampsia and parity. The number of fetal capillaries was significantly increased with preeclampsia (mainly in primi subgroup). CONCLUSION: In our study, the definite changes in macroscopical and microscopical variables in placentas of normal and preeclamptic women could be attributed to placental insufficiency especially in preeclamptic group and this may be a compensatory repair mechanisms to factors like hypoxia in order to provide better fetal growth.