Autonomic dysfunction, heart rate changes, and orthostatic intolerance (OI) prepregnancy and postpregnancy. Composite autonomic severity scores (CASS), including sudomotor subscores, adrenergic subscores, and totals, did not differ significantly prepregnancy and postpregnancy (paired t test, P=.48; P=.59; P=.81, respectively [n=9]). There was no significant difference in supine heart rate, standing heart rate (at 5 minutes), or heart rate increment on head-up tilt pre- and postpartum (paired t test, P=.29; P=.06; P=.07; respectively [n=10]). In addition, OI (as per the OI scale, see Patients and Methods section) did not differ significantly between groups (paired t test, P=.51 [n=10]). Error bars show mean ± SD.