AU, UK: Use is contraindicated.
US: Use is not recommended.

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

Risk Summary: This drug may increase the risk of fetus/newborn harm through its pharmacological action on calcium homeostasis (e.g., skeletal and other abnormalities). If used during pregnancy or pregnancy occurs while taking or after taking this drug, a potential hazard to the fetus should be evaluated.

Comments:
-Women of child-bearing potential should use highly effective contraception during treatment with this drug.
-If used in the treatment of pregnant women with life threatening hypercalcemia, infants should be monitored for hypocalcemia during the first few days after birth.

This drug has been shown to cross the placenta and has produced marked maternal and non-teratogenic embryo/fetal effects in rats and rabbits. It has been shown to increase the length of gestation and parturition in rats resulting in increasing pup mortality. In reproductive studies in rats and rabbits, doses equivalent to 0.6 to 8.3 times the highest human recommended dose resulted in maternal toxicity and embryo/fetal effects. When administered during the entire period of gestation in animals, it can cause bone mineralization defects, especially in long bones, resulting in angular distortion.
Bisphosphonates are incorporated into the bone matrix, and gradually released over periods of weeks to years; the extent of drug incorporation into adult bone and the amount available for release back into the systemic circulation, is directly related to the total dose and duration of bisphosphonate use. There are no data on fetal risk in humans; however, bisphosphonates cause fetal harm in animals, and uptake into fetal bone is greater than into maternal bone. The impact of variables such as time between cessation of bisphosphonate therapy to conception, the particular bisphosphonate used, and the route of administration (intravenous versus oral) has not been established. There are no controlled data in human pregnancy.

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 D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

See references

AU, UK: Use is contraindicated.
US: 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

Comments: The effects in the nursing infant are unknown.

A study in lactating rats has shown that this drug will pass into the milk. Very limited experience indicates maternal milk levels of this drug under the limit of detection. Moreover the oral bioavailability is poor, so the total absorption of this drug by a breastfed infant is not likely.

See references