Histomorphology of terminal villi of human placenta at low and high altitude with emphasis on blood capillaries

ABSTRACT

This cross sectional study is designed to compare the histomorphological characteristics of human placenta at high altitude [HA] i.e. Skardu [8500 ft] with those at low altitude [LA] i.e. Rawalpindi [1800 ft]. Cross sectional comparative study. Place and duration of study The study was conducted in the anatomy department of Army Medical College Rawalpindi, from October 2002 to April 2003. Eighty placentae, 40 each from normal cases at LA and HA, were included. Three full depth samples of placental tissue were taken. Histological study was done in Haematoxylin and eosin [H and E] and Periodic acid Schiff [PAS] stained sections. Detailed morphology of terminal villi was studied and number of capillaries was counted. The core of terminal villus in LA group contained few capillaries with considerable amount of stroma while in HA group it contained abundant dilated capillaries with very little stroma. Mean number of capillaries in LA and HA groups were 201.45 +/- 2.692 and 216.97 +/- 2.828 respectively. The capillaries in terminal villi were dilated and there number was significantly more in high altitude group probably showing adaptive changes in response to hypoxia