No, Diazepam is harmful for the baby both during pregnancy and breast feeding. Diazepam has the potential to cross the Placental barrier in pregnancy and also excrete in breast milk .It can cause lethal effects in newborn such as respiratory depression which can lead to mortality of the newborn. It can also cause hypotonia known as Floppy baby syndrome, in which baby don’t have any tone and feel limp, like a rag doll.nnDiazepam is classified in FDA pregnancy category D, which means there is possible risk to fetus.nncause other symptoms of CNS depression and withdrawal effects even in new born. It can lead to congenital malformations such as cleft palate.