Fetal stress increases fetal corticosterone, but not cortisol, synthesis.

<p>For emergent C-sections only (EC: N = 49), absolute increase [A-V] ng/ml in concentration after passage of the fetus for corticosterone (panel a) and cortisol (panel b) in groups stratified by the clinical rationale for the emergent C-section: fetal heart rate abnormalities (FHR: N = 11); Failure to progress in stage 1 (FTP1: N = 19), and failure to progress in Stage 2, representing cephalo-pelvic disproportion detected after a history of labor (FTP2: N = 14). Five EC cases were excluded because the chart record was not clear on the rationale for EC. Letters that differ indicate a significant post-hoc difference between groups, with FTP2 corticosterone higher than FHR and FTP1, following an overall effect of rationale for EC.G.