Dr. Mark Leondires

Founder and Medical Director; Reproductive Endocrinologist

Reproductive endocrinology and infertility LGBTQ+ family building

At Illume Fertility — Norwalk, CT 06851

About Dr. Mark Leondires

Mark Leondires, MD, is the founder and medical director of Illume Fertility and Gay Parents To Be and a board-certified reproductive endocrinologist. Practicing since 2002, he specializes in inclusive fertility care, donor conception, fertility preservation, and LGBTQ+ family building, informed in part by his own family-building experience through egg donation and surrogacy.

Education and training

Colby College

MD, University of Vermont

Obstetrics and Gynecology residency, Maine Medical Center

Reproductive Endocrinology and Infertility fellowship, National Institutes of Health

Awards and recognitions

Castle Connolly Top Doctor and America’s Top Doctors in Reproductive Endocrinology and Infertility (2013–present)

Path to Parenthood Visionary Award (2015)

Crain’s New York Notable Healthcare Leaders (2022)

Castle Connolly Top LGBTQ+ Doctor (2024)

Professional affiliations

Board-certified in Obstetrics and Gynecology and Reproductive Endocrinology and Infertility Founder and Medical Director, Illume Fertility and Gay Parents To BeRESOLVE Physician CouncilASRM Diversity, Equity and Inclusion Task ForceBoard, The Nest Egg FoundationMedical Advisor, GWK AcademyPast President, ASRM LGBTQ Special Interest Group