Effects of Pregnancy Induced Hypertension on Human Placenta

Abstract

Placenta is a unique organ which arise de novo, directly related to the growth and development of the foetus in the uterus. A thorough examination of the placenta inutero, as well as post-partum, gives valuable information about the state of the foetal well being. Pregnancy Induced Hypertension is a well recognized obstetric hazard and observed more frequently in developing countries. OBJECTIVES: The present study was undertaken to analyze placental changes in the pregnancy induced hypertension. MATERIAL AND METHODS: thirty placentae of mothers with uncomplicated pregnancy as control group and thirty with pregnancy induced hypertension as study group were studied with gross examination and histologically. RESULTS: Gross examination revealed presence of smaller placentae with foci of calcification and infarction in study group. On light microscopic examination, the striking villous abnormalities were observed in the study group which included increased Syncytial knots formation, fibrinoid necrosis, stromal fibrosis, hyalinized villi, altered villous vascularity (hypo vascularity), cytotrophoblastic cell proliferation, endarteritis obliterans, intervillous haemorrhage and basement membrane thickening. CONCLUSIONS: Pregnancy induced hypertension immensely affected placenta which may be responsible for wore postnatal outcomes. This study is of particular importance for Pathologists, Embryologists and Gynaecologists.

Comparative Study of Histology of Placenta in Normotensive and Hypertensive Cases

“…A significant increase in syncytial knot formation in placental villi indicates the disturbance in the hormonal factors, which may probably lead to altered morphometry of placenta resulting in PIH in the mother. In the present study, stromal fibrosis was also increased in hypertensive group which corresponds with the study of Rohini Motwani et al 13 , Heazella AEP et al 18 , Kristina L et al 19 and…”

“…15,16 Presence of syncytial knots increases with increasing gestational age, and with conditions of uteroplacental mal-perfusion and are important in placental examination. 17 In our study, increased syncytial knots in placenta were observed in 70% cases with severe hypertension whereas placenta of only 10% of normotensive mothers showed syncytial knots which was also reported by Rohini Motwani et al 13 , Heazella AEP et al 18 and Kristina L et al 19 They also hypothesized that the formation of syncytial knots may be induced by exposure to hypoxia. A significant increase in syncytial knot formation in placental villi indicates the disturbance in the hormonal factors, which may probably lead to altered morphometry of placenta resulting in PIH in the mother.…”

“…13,14 Also, the calcification and infarction of placenta increases with the increase in the severity of hypertension ( Table 1). The calcification of placenta near the end of pregnancy indicates 'aging' of the placenta, but it may be the sign of the premature aging in hypertension, which will decrease the amount of nutrition and oxygen going to the baby and may worsen the postnatal outcome.…”

“…14 As reported in other studies as well as in our study villus vascularity was lower in PIH group. 13,17,19,20 The reduced number of vessels may be due to their de-novo poor formation or secondary to fibrosis. 21 All the above changes in the placentae of hypertensive group may be due to reduced uteroplacental blood flow, which may be accountable for increase in maternal and foetal mortality and morbidity.…”

Placental changes in hypertensive pregnancy: a comparison with normotensive pregnancy

“…In different studies, placental weight in hypertensive pregnancies has been reported to vary from 345.96 g to 524.24 g whereas that in normotensive pregnancies ranged from 435.92 g to 557.8 g. 12,13 The difference in placental weight of two groups in present study was 77.77 g. Extent of this difference has ranged widely in different studies. Qureshi et al found this difference to be 33 g only while Motwani et al found it as 67 g, similar to our study, Kulandaivelu et al in their study reported it to be 73 g, however, on a higher note Nag et al found this difference to be as high as 94 g and Salmani et al even surpassed this and reported this difference as 124 g. [13][14][15][16][17] The profile of differences in placental weight between hypertensive group and normotensive groups in different studies might be due to difference in different types of HDPs included in the assessment. Studies reporting a higher difference generally have a higher component of severe HDPs like severe preeclampsia and eclampsia as compared to gestational hypertension.…”