Considerable controversy exists about the relative safety and effectiveness of single-holed versus multiholed epidural catheters in obstetric anesthesia. To assess the relative incidence of adverse effects with these catheters a series of parturients was randomly assigned to have epidural anesthesia administered via a single-holed or a multi-holed epidural catheter, all inserted via a 16-gauge Tuohy needle by means of a loss-of-resistance technique. All catheters were tested with 2% lidocaine and aspiration for blood and CSF performed. Each anesthetist then completed a standard questionnaire.