Increased Apoptosis in Chorionic Trophoblasts of Human Fetal Membranes with Labor at Term

Objective: To determine the association of apoptosis in the layers of human fetal membranes distal to rupture site with labor at term. Study Design: Fetal membranes were collected from elective cesarean sections (n = 8) and spontaneous vaginal deliveries (n = 8) at term. The extent of apoptosis within fetal membrane layers was determined using terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling (TUNEL) assay and western blots for pro-apoptotic active caspase-3 and anti-apoptotic Bcl-2. Results: Apoptotic index in chorionic trophoblasts of membranes distal to rupture site obtained after vaginal delivery was 3-fold higher than those obtained from elective cesarean (11.57% ± 4.98% and 4.05% ± 2.4% respectively; p = 0.012). The choriodecidua layers after vaginal deliveries had higher expression of the pro-apoptotic active caspase-3 and less expression of the anti-apoptotic Bcl-2 than those obtained from elective cesarean sections. Conclusions: Labor at term is associated with increased apoptosis in chorionic trophoblast cells of human fetal membranes distal to rupture site.