Spinal anesthesia is the most common anesthetic technique used for Cesarean delivery in the United States and across the world. Intrathecal opioids are administered with a local anesthetic during spinal anesthesia post-Cesarean delivery analgesia. The effectiveness of intrathecal morphine for post-Cesarean pain control is well established, and the use of intrathecal hydromorphone in this patient population is growing. No prospective studies have been conducted to specifically compare the efficacy of intrathecal morphine versus hydromorphone for post-Cesarean analgesia.