Cesarean section. Assessment of the convenience factor.

: To assess the potential input of physician convenience on the performance of cesarean sections (C-sections), analysis of C-sections by time of day and day of the week was undertaken at four Chicago-area hospitals. The primary C-section rate at the University of Chicago Chicago Lying-In Hospital, with a relatively high-risk patient population and a full-time salaried resident and faculty staff, was lower than at three other hospitals staffed predominantly by private practitioners. Indications for primary C-sections were classified as "acute," "semiacute" or "nonacute." Acute and semiacute C-sections were performed without demonstrated time biases in regard to the time of day or the day of the week at all four hospitals. Nonacute C-sections (70% cephalopelvic disproportion) were not performed as frequently at night (12-8 A.M.) as at other times at three of the four hospitals, but there were no differences in the individual characteristics of the outcomes of such deliveries between day and night. There was also no Friday afternoon or Monday morning frequency increase. The data failed to reveal significant variations in the performance of acute C-sections but did show day-night variability in C-sections done for non-acute indications.