Benefit should outweigh risk.

AU TGA pregnancy category: B3
US FDA pregnancy category: C

In animal studies, no embryonal/fetal toxicities were seen with the exception of decreased fetal body weights at doses associated with maternal toxicities.

Women who become pregnant during treatment should be encouraged to enroll in the Amgen Pregnancy Surveillance Program. Patients or their physicians should call 1-800-77-AMGEN (1-800-772-6436) to enroll.

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 C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

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This drug is excreted into the milk of lactating rats with a high milk-to-plasma ratio and is associated with decreased food consumption and reduced body weight gain of suckling rats.

A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.

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

Comment:
The effects in the nursing infant are unknown.

See references