Abstract
While careful consideration to avoid a second scourge like thalidomide is required, disadvantages for mothers and fetuses by restraint of necessary drug prescription because of too much concern about the effects on fetuses must be avoided. Information sources to evaluate teratogenicity of drugs themselves include epidemiological investigations, case reports, and animal reproduction studies and are considered more reliable in this order. And breast milk is the best source of nutrition and it also serves as a source of substances providing immunity for a newborn infant. However, there are times when nursing mothers may have to take some kind of medication, so it is necessary to evaluate the effect of drugs that are transferred to infants through breast milk, and to select medications with minimal adverse effects.
