Barbara Luke, Sc.D., M.P.H., R.N., R.D., is a professor in the Department of Obstetrics, Gynecology, and Reproductive Biology at Michigan State University. She has published numerous research studies on multiple pregnancy through the University Consortium on Multiple Births, with colleagues from universities around the country. She is also the author of Every Pregnant Woman's Guide to Preventing Premature Birth and coauthor, with Tamara Eberlein, of Program Your Baby's Health.