Background and Objectives To compare the duration of pain relief and incidence of side effects using two subarachnoid administered drug combinations for labor analgesia: fentanyl 25 μg with morphine 0.25 mg or sufentanil 10 μg with morphine 0.25 mg.

Methods Thirty healthy term primagravid patients with cervical dilation ≤5 cm consented to participate in this prospective, randomized, double-blind study. Patients received the assigned drug combination subarachnoid with simultaneous epidural catheter placement using a double needle technique. The authors recorded blood pressure and patient’s rated pain, nausea, and pruritus using 10-cm visual analog scales at 0, 5, 10, 15, 20, 25, 30, and every 30 minutes until the patient requested additional analgesia.

Results The onset of analgesia was rapid in both groups. The mean duration of analgesia was similar; 114 ± 55 minutes in the fentanyl and morphine group and 134 ± 79 minutes in the sufentanil and morphine group. The sufentanil and morphine group experienced more severe pruritus (P = .015).

Conclusions Both fentanyl and morphine and sufentanil and morphine provide adequate labor analgesia for about 2 hours. Patients who receive sufentanil experience more severe pruritus.