We evaluated the efficacy of a new method of induction of epidural obstetric analgesia devised by us. The upper and lower catheters used for the epidural double-catheter method were connected to a compression-type disposable injector (Coopdech Syrinjector). 0.125 % bupivacaine + 2 microg/ml fentanyl (6 ml/h) were serially injected via the upper catheter. In the latter half of Stage 1 of labor, the same drugs were continuously infused via the lower catheter (4 ml/h). The mean number of additional drug doses administered via the upper catheter was 0.67+/-0.90 (range: 0-3) when the analgesia induction was commenced after the cervix was dilated to 8 cm in nulliparous women or 6 cm in multiparous women. The method of analgesia was found to be more effective than the conventional method (uncombined continuous infusion of a local anesthetic) for alleviating the pain of the latter half of Stage 1, and Stage 2 of labor. The mean number of additional drug doses injected via the lower catheter was 0.37+/-0.57(range: 0-2). The number of additional doses in the 49 women averaged 0.16 per hour and 1.04 per delivery. Thus, good results were obtained.