Ephedrine and phenylephrine are useful vasopressors for managing hypotension during caesarean delivery. Fetal arterial cord blood pH and fetal acidosis may be related to the choice of vasopressor. The present study was therefore designed to compare arterial cord blood pH and fetal acidosis rates by vasopressor treatment, while maintaining maternal mean arterial pressure (MAP) near baseline values. Fifty one ASA I-II parturients undergoing cesarean delivery (CD) under combined spinal-epidural anesthesia (CSEA) were randomly assigned to prophylactic infusion (20 mL.hr-1) of phenylephrine (100 µg.ml-1, n=25) or ephedrine (3 mg.ml-1, n=26) prior to CSEA. The infusion, was titrated to maintain mean arterial pressure (MAP) near baseline values. The primary outcome was arterial cord blood pH. Fetal acidosis was defined as pH <7.2; maternal hypotension as MAP <70 mmHg; and maternal bradycardia as heart rate <50 bpm. Arterial cord blood pH was 7.32±0.06 in the ephedrine group vs. 7.32±0.05 in the phenylephrine group, p=0.9. Fetal acidosis occurred in one case (4%) in each study group with similar one- and five-minute Apgar scores (all >7). Hypotension episodes were more frequent in patients given ephedrine (10 patients; 38%) than phenylephrine (three patients; 12%), (p=0.03). We conclude that prophylactic ephedrine as compared to phenylephrine administration was associated with a relatively high incidence of hypotension but with similar cord blood pH.