List two different classifications of drugs used for pain relief during labor and birth, and include potential side effects of the drugs on the fetus.

During labor and delivery, narcotics analgesics are used to relieve pain. Regional anesthetics can also be prescribed. The opioids or narcotic analgesics are drugs that reduce pain by acting on the opioid receptors of the spinal cord and brain. They can be administered either intravenously, intramuscularly, or both. Examples of common narcotics that are used during labor and delivery includes fentanyl (morphine), hydromorphone, meperidine, butorphanol (Stadol), and buprenorphine. Some of the side effects that these types of medications can cause include a decreased fetal cardiac rate and respiratory depression. These effects, however, are temporary and usually reversed by supportive care.

Local injections in specific body areas block the nerve signals that reach the brain, resulting in localized anesthesia. Common regional anesthetic options used during labor include epidural blocks – which provide temporary relief from lower abdominal pains by injecting a local anesthetic into the lumbar region – as well as pudendal nerve blocks which block sensation in the pelvic area. While regional anesthetics are known to cause hypotension and drowsiness, when they’re administered properly by trained staff, these drugs can be much more effective than opioids.