DES can no longer be prescribed to pregnant women, even for use in clinical studies. To project future health risks of DES exposure, scientists are conducting animal studies with laboratory mice. Scientists administer DES to pregnant female mice and then study the results. Because mice age more quickly than humans, these studies can be used to explore future health risks. Using laboratory animal models allows scientists to pursue hypotheses that are not possible to research in humans. Results from these animal studies can also guide them on the types of diseases and health effects to look for in humans. Although laboratory animal studies can often predict human health effects, because of differences between humans and mice, the results of laboratory animal studies are not always transferable to humans. In addition, studies of humans rely on tracking the outcomes of DES cohorts (women and men already exposed to DES).