Dr. Joshua Klein leads the medical practice at Extend Fertility and is a board-certified reproductive endocrinologist and assistant professor of Obstetrics, Gynecology & Reproductive Science at the Icahn School of Medicine at Mount Sinai. Prior to co-founding Extend Fertility, Dr. Joshua practiced for several years at one of the largest academic IVF programs in the US. He has authored numerous scientific and academic publications and has been named a Super Doctor every year since 2017. He holds credentials from Harvard and Columbia University.