It is recommended not to use Regpara in pregnant women or in women who may possibly be pregnant. The safety of Regpara during pregnancy has not been established. Hypocalcemia, suppressed weight gain and decreased food consumption in dams, as well as decreased weight in fetuses, were observed in animal studies (using rats and rabbits). Furthermore, cinacalcet was reported to be transferred through the placenta in animal studies (using rats and rabbits).
It is not known whether cinacalcet is excreted in human milk. Cinacalcet is excreted in the milk of lactating rats with a high milk to plasma ratio. A transient suppression of weight gain was also observed in rats newborns. Following careful benefit/risk assessment, a decision should be made to discontinue either breast-feeding or treatment with cinacalcet.