Peter Nathanielsz, M. D., Ph. D., Sc. D., is director of the Laboratory for Pregnancy and Newborn Research at Cornell University. He is the author of Life Before Birth and Life in the Womb, and lives in Ithaca, New York.
Christopher Vaughan has been writing about health and science for fifteen years. The author of How Life Begins and the coauthor of The Promise of Sleep, he lives in Menlo Park, California.