Differential apoptotic activity in trophoblast of spontaneous abortions and normal pregnancies

Apoptosis is a key process during normal trophoblastic development and, consequently, the whole gestation. However, in trophoblastic differentiation in spontaneous abortions apoptosis has been hardly investigated. Therefore, the aim of the study was to investigate the correlation between apoptotic frequency in trophoblast and spontaneous abortion incidences. A total of 72 trophoblastic tissue samples were immunohistochemically examined. 42 of 72 derived from first-trimester spontaneous abortions and the remaining 30 from elective terminations during the same trimester of pregnancy. TUNEL assay and M30 marker were used for apoptosis evaluation by immunohistochemistry. Comparative study of tissues from spontaneous abortions and elective pregnancy terminations demonstrated increased expression of both apoptotic markers in tissues derived from spontaneous abortions compared to normal pregnancies. In addition, statistical analysis correlated maternal age and gravidity with increased spontaneous abortion incidences. Moreover, both M30 and TUNEL staining were significantly correlated with maternal age and primigravidity in spontaneous abortion cases. Our data proved that elevated apoptotic activity during the first pregnancy trimester is clearly involved in spontaneous abortions. Moreover, two well-established apoptotic markers revealed high statistical significance in the evaluation of post-abortive tissues.