This drug should be used during pregnancy only if clearly needed and the benefit outweighs the risk to the fetus.

AU TGA pregnancy category: B3
US FDA pregnancy category: Not assigned.

Risk summary: Insufficient data available on use of this drug in pregnant women to inform a drug-related risk.

Comments:
-A pregnancy exposure registry is available.
-Use of effective contraception has been recommended.

Animal studies have failed to reveal evidence of teratogenicity or embryofetal toxicity at clinically relevant exposures; embryofetal toxicity was not seen with oral doses 28 (rat) and 212 (rabbit) times the human exposure (AUC) at the maximum recommended human dose (MRHD). In rats, maternal toxicity and embryofetal toxicity (including postimplantation loss, resorptions, tail and vertebral malformations, skeletal variations [including reduced ossification, extra lumbar vertebrae and ribs], decreased fetal weights) were observed at systemic exposures (AUC) 3100 times those in humans at the MRHD; in rabbits, embryofetal toxicity (including postimplantation loss, resorptions, skeletal variations [including reduced ossification, increased incidence of 13th rib]) were observed at systemic exposures (AUC) 883 times those in humans at the MRHD. There are no controlled data in human pregnancy.

To monitor maternal-fetal outcomes of pregnant women exposed to antiretroviral therapy, an Antiretroviral Pregnancy Registry (APR) has been established. Healthcare providers are encouraged to prospectively register patients. For additional information: apregistry.com

The APR has not received sufficient numbers of reports regarding exposures to this drug to estimate rate of birth defects.

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

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.

See references

An alternative agent may be preferred, particularly while breastfeeding newborn or preterm infants.
-According to some authorities: Breastfeeding is not recommended during use of this drug.

Excreted into human milk: Unknown
Excreted into animal milk: Yes

Comments:
-This drug has not been studied in nursing mothers receiving treatment for hepatitis B virus infection.
-Developmental and health benefits of breastfeeding should be considered as well as the mother's clinical need for this drug.
-The effects in the nursing infant are unknown; potential side effects in the breastfed child due to this drug or the mother's underlying condition should be considered.

See references