Neural tube defects were reported with subcutaneous administration of this drug to pregnant hamsters on gestation day 8; the finding cannot be clearly attributed to maternal toxicity. This drug has been frequently used in pregnancy and during labor without apparent harmful effects; however, prolonged use of opioids, whether for medical or nonmedical reasons, can result is physical dependence in the neonate and neonatal opioid withdrawal after birth. Use of this drug during labor produces respiratory depression in newborns that is both time and dose dependent. There are no controlled data in human pregnancy.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

Benefit should outweigh risk

AU TGA pregnancy category: C
US FDA pregnancy category: Not assigned

Risk Summary: Prolonged use during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated. Use during labor and deliver may produce respiratory depression requiring resuscitation.

Comments:
-Prolonged use of opioids during pregnancy can result in physical dependence in the neonate; women should be advised of the risk of neonatal abstinence syndrome and ensure that appropriate treatment will be available.
-Monitor neonates exposed to opioid analgesics during labor for signs of excess sedation and respiratory depression.

See references

Benefit should outweigh risk; the developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for this drug.

Excreted into human milk: Yes

Comments:
-If used, monitor breastfed infants for excess sedation and respiratory depression.
-Withdrawal symptoms may occur in breastfed infants when maternal administration of an opioid is stopped or when breast-feeding is stopped.

A single dose used for anesthesia or conscious sedation in older breastfed infants does not appear to cause problems. However, maternal use of narcotics may cause sedation, CNS depression and even fatalities in breastfed infants, especially newborn infants. This drug is metabolized to an active metabolite, which has half the analgesic activity but double the CNS excitatory activity of the parent drug. Other medications are generally preferred over this drug during breastfeeding.

See references