200 West 57th Street, Suite 1101
New York, NY 10019


Meet The Team

This dedicated team of physicians, healthcare professionals, and staff is working diligently to make Extend Fertility’s vision of fertility preservation a reality. Say hello.

Dr. Joshua U. Klein

Dr. Joshua U. Klein, MD, FACOG

Chief Medical Officer, Reproductive Endocrinologist, Medical Director of the Embryology Lab

Dr. Joshua U. Klein, co-founder of Extend Fertility, is the chief medical officer of Extend Fertility Medical Practice as well as the chief clinical officer and medical director, embryology lab, of Extend Fertility LLC.

Dr. Klein is an accomplished board-certified reproductive endocrinologist and assistant professor of Obstetrics, Gynecology, and Reproductive Science at the Icahn School of Medicine at Mount Sinai. He earned his medical degree at Harvard University, completing his residency in Obstetrics, Gynecology and Reproductive Biology at Massachusetts General and Brigham & Women’s Hospitals. He did his fellowship in Reproductive Endocrinology and Infertility at Columbia University and is board-certified in Obstetrics and Gynecology as well as Reproductive Endocrinology and Infertility.

Before leading the Extend Fertility Medical Practice, Dr. Klein practiced for several years at one of the largest academic IVF programs in the US, where he served as medical director for Reproductive Medicine Associates of New York in Brooklyn. Dr. Klein has authored and co-authored publications in leading peer-reviewed academic journals such as Science, Fertility and Sterility, and Obstetrics and Gynecology. He has also written numerous chapters for medical textbooks and has presented research at national conferences including the American Society for Reproductive Medicine (ASRM). Dr. Klein sits on the medical board of several fertility advocacy organizations and regularly gives lectures and presentations to community groups on infertility and fertility preservation.

Dr. Klein’s extensive professional experience has made clear to him that despite the miraculous advances that have been made in infertility treatment, women in the 21st century continue to struggle to reconcile the biological realities of reproductive aging with the social and economic realities they face every day. As such, he is passionate about helping women understand their fertility and make smart, informed, and individualized decisions about their options for planning a family, and he is excited to help lead Extend Fertility’s team in realizing that vision.