Joanne Stone, MD, is a full-time faculty member in the internationally renowned Division of Maternal-Fetal Medicine at The Mount Sinai Medical Center in New York City. She is the director of the Perinatal Ultrasound Unit and also cares for patients with problem pregnancies. She has lectured throughout the USA, is widely published in medical journals, and has been interviewed frequently for television and magazines on topics related to pregnancy, with a special emphasis on the management of multifoetal pregnancies. She was a co-star in the critically acclaimed series Pregnancy For Dummies on the Discovery Health Channel. Away from the hospital she loves to spend time with her husband, George, and her two little girls, Chloe and Sabrina. Keith Eddleman, MD, works with Joanne at Mount Sinai. He is also a full-time faculty member and is the Director of the Division of Maternal-Fetal Medicine. He teaches medical students, residents, and fellows; lectures throughout the world; and appears often on television to discuss issues concerning the care of pregnant women. His areas of special expertise are ultrasound and reproductive genetics. He was also a co-star on the critically-acclaimed series Pregnancy For Dummies on the Discovery Health Channel. His free time, when he has any, is split between spending time with his family at their apartment in Manhattan or at their country house in upstate New York. Mary Duenwald is a writer and editor who has for many years specialized in medicine and science journalism. She has written for The New York Times, Discover, Smithsonian, and Departures. She has been executive editor of Harper's Bazaar, Women's Sports & Fitness, and The Sciences magazines and a senior editor for Vogue. She is currently a contributing editor for GQ. She is also the mother of 14-year-old twins, Nick and Claire Murray. Dr Sarah Jarvis is a GP and GP trainer in inner city London. She is a Fellow of, and the Women's Health spokesperson for, the Royal College of General Practitioners (RCGP). She was a founder member, and later chair, of the Women's Taskforce at the RCGP. She was also the medical advisor/presenter of the television series, The Maternity Guide, on Channel Health. She is also a medical writer and broadcaster, and appears regularly on Radio Five Live, GMTV, and ITN lunchtime news, as well as being the Radio 2 doctor. She writes regularly for a variety of magazines, including Good Housekeeping, Women's Health, Pregnancy, and Baby and You. Her great passion (as far as work is concerned) is patient education, and she has written over 500 patient information leaflets, as well as two previous books, A Younger Woman's Diagnose-It-Yourself Guide to Health and Diabetes For Dummies. Her other great passion is her family, and she loves spending time with her husband, Simon, their two children, Seth and Matilda, and their dog, Dascha.