Can ethnopharmacology contribute to the development of anti-fertility drugs?

China, one of the developing countries with approx. one-fifth of the world population, has been making great efforts in controlling her population size. One of the efforts being stressed is to look into the practicability of employing Chinese herbal medicine for fertility control. The rich ethnopharmacological descriptions in the ancient books of herbal remedy and those scattered in the folklore medicine contribute the possibility of this approach. After a discussion concerning the facets of antifertility drugs linked with male or female fertility regulation, several selected examples are presented, which include yuehchukene (isolated from Murraya paniculata), pseudolarix acids A and B (from Pseudolarix kaempferi), mardekoside A (from Mardenia koi), gardenic acid and gardenodic acid A (from Gardenia jasminoides) as early pregnancy terminating agent, for fertility regulation in females; whereas gossypol (from cottonseed oil) and total glycosides of Tripterygium wilfordii (GTW) as antispermatogenic agent for fertility regulation in males. Further research and development strategies of antifertility drugs from herbal medicines have also been discussed based on a collective research data in this field worldwide.