Data from non random groups of deliveries with some identical clinical factors were compared and certain conclusions are suggested. Most x-ray examinations which cause significant fetal exposure are pelvimetries. There appears to be no uniform set of indications for performing pelvimetry. Instead, the criteria seem to vary from hospital to hospital and even from physician to physician within the same hospital. A normal pelvimetry gives the physicina little confidence that a cesarean section will not be necessary. The duration of labor is not significantly altered by pelvimetry in those cases needing a cesarean section for cephalopelvic disproportion or following unsuccessful oxytocin stimulation.