Anaesthetic management was standardized in all studied patients. Oral ranitidine 150 mg was given the night before and on the morning of surgery, with 0.3 mol/L sodium citrate (30 mL) given 15 min before induction. In the operating theatre women were positioned supine on the operating table with 15° firm rubber wedge under the right hip to effect left uterine displacement. A slow 500-mL i.v. infusion of lactated Ringer's solution was given to all subjects over 20 min.