Reproductive toxicity tests: retrospect and prospect.

1. The design of the classical three segment reproductive test for new drugs is described and the relative merits of the USA/EEC and the Japanese guidelines are discussed. 2. The importance of pharmacokinetic studies in the interpretation of teratology studies and extrapolation to humans is mentioned in relation to caffeine, sodium valproate and cyclophosphamide. 3. Changing ideas on the design of multi-generation studies are reviewed. 4. Recent developments in the fields of behavioural teratology, chemicals in breast milk and transplacental carcinogenesis are described.