In animal studies no teratogenic effects were observed; however, there was an increase in embryolethality (increased post-implantation loss and the number of dams with all fetuses dead or resorbed). There are no controlled data in human pregnancy.

To monitor the outcomes of pregnant women exposed to Lemtrada (R), a pregnancy registry has been established. Physicians are encouraged to register patients by calling 1-866-758-2990 or online at [email protected].

AU TGA pregnancy category B2: 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 are inadequate or may be lacking, but available data show no evidence of an increased occurrence of fetal damage.

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.

Use is contraindicated.

AU TGA pregnancy category:
-Lemtrada: B3
-Mabcampath: B2
US FDA pregnancy category: Not assigned

Risk Summary: Based on findings from animal studies, this drug may cause fetal harm when administered to a pregnant woman. Available data studies in pregnant women are insufficient to establish an associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. It was embryolethal in mice when administered during organogenesis. Human IgG antibodies are known to cross the placental barrier; therefore, this drug may be transmitted from the mother to the developing fetus.

Comments:
-A pregnancy exposure registry is available.
-This drug induces persistent thyroid disorders. Untreated hypothyroidism in pregnant women increases the risk for miscarriage and may have effects on the fetus including mental retardation and dwarfism. In mothers with Graves' disease, maternal thyroid stimulating hormone receptor antibodies can be transferred to a developing fetus and can cause neonatal Graves' disease.
-If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus.
-Women of childbearing potential should use effective contraceptive measures when receiving this drug and for 4 months after.
-Infants born to pregnant women treated with this drug may be at increased risk of infection.

See references

No information is available on the use of this drug during breastfeeding. Because it is a large protein molecule, the amount in milk is likely to be very low and absorption is unlikely because it is probably destroyed in the infant GI tract. Until more data become available, this drug should be used with caution or avoided during breastfeeding, especially while nursing a newborn or preterm infant.

Use is contraindicated.

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

Comments:
-The effects in the nursing infant are unknown.
-IgG antibodies, such as this drug can be excreted in human milk.
-Because of the potential for serious adverse reactions from this drug in a breastfed child, including reduced lymphocyte counts, advise women not to breastfeed during therapy and for at least 3 months after.

See references