What are the pain management options during labor and delivery, and what are their potential adverse effects on the fetus?

From the Guidelines

Pain management during labor and delivery should prioritize non-pharmacological methods and regional anesthesia, such as epidural analgesia, to minimize adverse effects on the fetus, as supported by the most recent evidence from 2024 1.

Non-Pharmacological Options

Non-pharmacological methods for pain management during labor and delivery include:

• Breathing techniques
• Massage
• Hydrotherapy
• Transcutaneous electrical nerve stimulation (TENS)
• Hypnobirthing These methods have minimal to no adverse fetal effects and can be used in combination with other methods to provide effective pain relief.

Pharmacological Options

Pharmacological options for pain management during labor and delivery include:

• Systemic opioids like morphine, fentanyl, and remifentanil, which can cause fetal respiratory depression, decreased heart rate variability, and lower Apgar scores if administered close to delivery 1
• Nitrous oxide, which provides mild analgesia with minimal fetal effects but may cause maternal nausea and dizziness
• Regional anesthesia, particularly epidural analgesia, which offers effective pain relief with minimal direct fetal effects, though it may prolong labor and increase the need for instrumental delivery 1
• Combined spinal-epidural techniques, which provide rapid onset with long-lasting relief
• Local anesthetic infiltration for perineal repair, which has no significant fetal effects

Adverse Effects on the Fetus

The potential adverse effects on the fetus from pain management during labor and delivery include:

• Fetal respiratory depression
• Decreased heart rate variability
• Lower Apgar scores
• Fetal bradycardia, which can occur with the use of intrathecal opioids 1 It is essential to consider the timing of pain management and avoid opioids within 2-4 hours of anticipated delivery to minimize neonatal respiratory depression.

Recommendations

The ideal approach to pain management during labor and delivery is a multimodal approach that combines non-pharmacological methods, regional anesthesia, and pharmacological options, tailored to the individual's preferences, labor progression, and medical circumstances, as recommended by the most recent evidence from 2024 1.

From the FDA Drug Label

Local anesthetics, including ropivacaine, rapidly cross the placenta, and when used for epidural block can cause varying degrees of maternal, fetal, and neonatal toxicity[see Clinical Pharmacology (12)]. Adverse reactions in the parturient, fetus and neonate involve alterations of the central nervous system, peripheral vascular tone and cardiac function. Maternal hypotension has resulted from regional anesthesia. Local anesthetics produce vasodilation by blocking sympathetic nerves Therefore, during treatment of systemic toxicity, maternal hypotension or fetal bradycardia following regional block, the parturient should be maintained in the left lateral decubitus position if possible, or manual displacement of the uterus off the great vessels be accomplished.

The pain management options during labor and delivery include local anesthetics such as ropivacaine. The potential adverse effects on the fetus include:

• Alterations of the central nervous system
• Peripheral vascular tone
• Cardiac function
• Fetal bradycardia
• Maternal hypotension These effects can occur due to the rapid crossing of the placenta by local anesthetics, including ropivacaine, when used for epidural block 2 2.

From the Research

Pain Management Options During Labor and Delivery

The following are some of the pain management options available during labor and delivery:

• Epidural analgesia: considered the most efficient method of pain relief during labor 3
• Systemic pharmacologic agents:
  • Opioids (e.g. meperidine, nalbuphine, tramadol, butorphanol, morphine, and remifentanil) 3
  • Non-opioid agents (e.g. parenteral acetaminophen and nonsteroidal anti-inflammatory drugs) 3
• Nonpharmacologic methods:
  • Relaxation techniques (e.g. yoga, hypnosis, and music) 3
  • Manual techniques (e.g. massage, reflexology, and shiatsu) 3
  • Acupuncture 3
  • Birthing ball 3
  • Transcutaneous electrical nerve stimulation 3

Potential Adverse Effects on the Fetus

The potential adverse effects on the fetus due to pain management options during labor and delivery include:

• Respiratory depression: a dose-related side effect of opioids 4
• Neonatal hypothermia: a possible side effect of tranquillizers such as diazepam 4
• Poor muscle tone of the newborn: a possible side effect of tranquillizers such as diazepam 4
• Altered adaptive functions of the newborn: a possible side effect of systemic analgesia, particularly with moderate to large doses of opioids 4
• Effects on gastric emptying, maternal temperature control, and hemodynamic changes to the mother and fetus: potential complications of epidural analgesia 5