Altered Trophoblastic Apoptosis in Early Pregnancy Losses

Lee, P Y; Kim, B H; Yoo, H K; Won, H S; Park, E J; Lee, J H; Lee, I S; Huh, J R; Kim, A; Nam, C H

Abstract

OBJECTIVE
Our purpose was to investigate whether trophoblastic apoptosis is related with early pregnancy losses.
METHODS
Placentas were collected from 22 uncomplicated first-trimester pregnancies undergoing elective surgical abortion for social reason and from 27 women of first-trimester pregnancy loss. Hematoxylin & eosin staining and terminal deoxyuridine triphosphate nick end labeling[TUNEL] were used to identify apoptosis. Over 5,000 cells were exmined at a magnification of x400. Mann-Whitney U test and Spearman rank correlation were used for statistical analysis.
RESULTS
There were no cerrelations between the incidence of apoptotic trophoblasts and gestational age in each of the control and failing pregnancies. The incidence of apoptosis was significantly higher in failing pregnancies[median 0.23%, range 0.0% to 0.46%]than in uncomplicated pregnancies[median 0.09%, range 0% to 0.28%][p<0.05]. Apoptotic cells were detected in both syncytiotrophoblast and cytotrophoblasts. However, the relative incidence of apoptosis in syncytiotrophoblast comparing to that in cytotrophoblasts was increased significantly in failing pregnancies than in control pregnancies[23.5 -1.0% vs 12.0 -1.3%:mean -standard error of mean][p<0.05].
CONCLUSIONS
Trophoblastic apoptosis, especially that of syncytiotrophoblast, may play a certain role in the phthophysiology of early pregnancy losses.