About us

Co-founder, Chief Clinical Officer, Reproductive Endocrinologist, Medical Director of the Embryology Lab

Dr. Klein is a 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. He is a Castle Connelly Top Doctor and has been named a Super Doctor each year since 2017.

Chief Scientific Officer, Reproductive Endocrinologist

Dr. Nataki C. Douglas is board certified in both obstetrics and gynecology and reproductive endocrinology and infertility. Dr. Douglas earned both her MD and PhD at Yale University School of Medicine. She completed her residency in obstetrics and gynecology as well as her fellowship in reproductive endocrinology and infertility at Columbia University Medical Center. Prior to joining the Extend Fertility Medical Practice as a consulting reproductive endocrinologist, Dr. Douglas practiced at the Center for Women’s Reproductive Care at Columbia University for 8 years.

As a practicing physician-scientist, Dr. Douglas combines basic/translational and clinical research into comprehensive patient care. As an associate professor and director of translational research for the Department of Obstetrics, Gynecology and Women’s Health at Rutgers-New Jersey Medical School, her research focuses on understanding what is required by the uterus for successful embryo implantation and pregnancy. Dr. Douglas has authored and co-authored publications in leading peer-reviewed academic journals including Human Reproduction, Fertility and Sterility, Endocrinology, and Obstetrics and Gynecology, and has presented her research at national conferences for the American Society for Reproductive Medicine (ASRM) and the Society for Reproductive Investigation (SRI).

Dr. Abittan is board certified in obstetrics and gynecology and board eligible in reproductive endocrinology and infertility. He is committed to bringing patients the highest level of care with cutting edge techniques and treatments and has developed and led research studies aimed at optimizing IVF success rates.

Dr. Abittan was accepted to an accelerated undergraduate and medical program and subsequently earned his medical degree from the Commonwealth Medical College. He completed his residency at North Shore University Hospital and Long Island Jewish Medical Center, during which he was appointed research chief resident. Dr. Abittan stayed on Long Island to complete his fellowship in reproductive endocrinology and infertility at Northwell Health Fertility.

Dr. Abittan is passionate about working with all patients, couples and families to achieve their personalized fertility goals. As such he spent his fellowship training researching and focusing on the optimal IVF protocol for patients with diminished ovarian reserve, as well as modifiable lifestyle affecting the genetic makeup of embryos.

He is a member of several professional organizations including American Society for Reproductive Medicine (ASRM), American College of Obstetrics and Gynecology (ACOG) and American Medical Association (AMA).

An accomplished researcher, Dr. Abittan has contributed to more than 45 presentations across the globe on topics including IVF success, frozen embryo transfer, preimplantation genetic testing (PGT) of embryos, and early prediction of IVF outcomes. He is currently actively involved in multiple prospective research trials, and has served as a peer-reviewer for several medical journals including the Journal of Assisted Reproduction and Genetics (JARG).
A father of young children, Dr. Abittan hopes to bring the gift of family to all of his patients.

Dr. Meir Olcha is a double board-certified OBGYN and Reproductive Endocrinologist. He has a warm heart and is committed to providing excellent, personalized, and compassionate care to all of his patients. He strives to be a leader in the field and works to improve reproductive health outcomes through progressive research and innovative medical treatments.

His current research focuses on improving access to fertility care as well as identifying genetic causes of implantation and pregnancy failure. He has published in numerous prestigious medical journals, has been awarded both federally funded and private grants, and has been invited to give talks at national fertility conferences throughout the country. He has been nominated for several excellence in teaching awards and was the recipient of the Arnold P. Gold Humanism Award.

Dr. Olcha graduated with honors from Rutgers University with a Bachelor of Science in Biology. His passion for helping others lead him to pursue a career in medicine, earning a Medical Degree from Rutgers – Robert Wood Johnson Medical School in 2010 and completing residency in Obstetrics and Gynecology at the same institution. Afterwards, he was accepted as an academic faculty scholar in the Department of Obstetrics, Gynecology and Reproductive Sciences where his clinical responsibilities included caring for obstetric and gynecological patients, performing complex gynecological surgeries, and routinely teaching both medical students and residents. Education is a great passion of his and as such is an integral part of his professional responsibilities.

Dr. Olcha is excited to be a part of the Extend Fertility team and is looking forward to dedicating his time to help people achieve their reproductive goals.

Dr. Melvin H. Thornton, II is recognized as one of the world’s leading experts in egg donation and surrogacy. He is double board certified in Reproductive Endocrinology and Infertility as well as Obstetrics and Gynecology. Dr. Thornton received his medical degree from Washington University in St. Louis, completed his internship and residency at the University of Southern California, and received additional training in advanced reproductive surgery at The Cleveland Clinic. He joined the faculty at Columbia University where he served as Medical Director and Director of the Egg Donation Program at the Center for Women’s Reproductive Care (CWRC).

Dr. Thornton has been helping families achieve their dreams of having children for over 20 years. Dr. Thornton has published more than 50 papers, written several book chapters, and presented over 100 abstracts at national conferences on topics related to infertility, third party reproduction, and women’s health. He has distinguished himself through his extensive research in the treatment of HIV sero-discordant couples and the relationship to infertility and fertility treatment. Although his interests include all aspects in the treatment of infertility, he is particularly recognized as being one of the world’s leading experts in egg donation and surrogacy.

He is currently an Associate Professor at Quinnipiac University and provides lectures in reproductive medicine and infertility to OB/GYN residents at New York Medical College. He is an excellent educator and gives board review lectures for OB/GYN, Family Medicine and Pediatrics residents preparing for their board examination.  He previously was a member of the ACGME Clinical Competency Committee for Obstetrics and Gynecology at Columbia and currently sits on the ASRM Education Committee. He is a Castle Connolly National Top Doctor, and was awarded the Top Doctors New York Metro Area Award in 2017, 2018, 2019, 2020, 2021 and 2022.

Currently Dr. Thornton is an affiliated physician with Extend Fertility, and is not accepting new patients.

Dayna is a board-certified nurse practitioner in family health with over a decade of nursing experience. She earned her Bachelor of Science in Nursing at Florida Atlantic University, Master of Science in Nursing from Nova Southeastern University and Master of Business Administration from University of Florida. Dayna is a member of the American Society for Reproductive Medicine (ASRM).

Dayna began her nursing career working in the emergency department and then moved on to serve as an operating room nurse. Building on her practical nursing experience, Dayna transitioned to a position as a fertility nurse for Reproductive Medicine Associates of New York in 2012, where she spent three years before joining the Extend Fertility Medical Practice in 2016.

While working in the reproductive endocrinology field, Dayna found time to teach health to high school students, fulfilling her love to educate, inform and share information. Dayna is committed to increasing the quality of patient care through efficient operations and patient education.

After completing her nursing degree at New York University Rory Meyers School of Nursing, Ilana spent two years at a nurse on a medical-surgical floor at Mount Sinai Hospital. She then moved to the burn intensive care unit at New York Presbyterian Weill Cornell Medical Center, where she worked with critically ill adults and pediatric patients for four years.

During her final year at Weill Cornell, she also took a per diem position as a nurse in their in vitro fertilization clinic. It was there that she discovered her love for the fertility field, and that experience inspired her to pursue a career in fertility medicine. Ilana is currently continuing her education at Hunter College, where she’s enrolled in their Psychiatric Mental Health Nurse Practitioner program.

Joining Extend Fertility fulfilled Ilana’s desire to work in a smaller, more intimate setting, as opposed to the large hospital setting she was used to. As a member of our team, she’s proud to be part of a constantly evolving industry that’s doing meaningful work, enabling women to have children at a time that works best for them.

Prior to Dawn’s tenure at Yale Fertility Center as Director of the IVF Laboratory, she has served as Lab Director at several noteworthy and high-performing labs, including RMA of Connecticut and Genesis Fertility Centre. Dawn’s clinical expertise includes trophectoderm biopsy and vitrification of blastocysts and oocytes.

Dawn obtained a BSc in Molecular Biology and Genetics followed by MSc and PhD in Biomedical Sciences at the University of Guelph, Canada. She is board certified as a High Complexity Laboratory Director. Dr. Kelk is an active member of ASRM, Society of Reproductive Biologists and Technologists (SRBT) and American Board of Bioanalysts (ABB).

Mr. Lo, a Canadian citizen, joined Extend Fertility as Laboratory Supervisor. His background spans clinical embryology, biology, cryobiology, cryopreservation, and micromanipulation.

In 2001, Mr. Lo earned a BS in Biology, Cell Biology, and Genetics Option from the University of British Columbia in Vancouver, Canada. Upon graduating, Mr. Lo worked in various scientific positions, including Laboratory Assistant at the University of British Columbia’s Center for Disease Control, Microinjectionist for the Center of Molecular Medicine and Therapeutics in Vancouver, and a Scientific Technician with the Genesis Fertility Center in Vancouver. In 2010, Mr. Lo was granted a TN nonimmigrant visa which allowed him to assume the role of Scientific Technician at the Reproductive Medicine Associates of Connecticut. In this role, Mr. Lo was responsible for oocyte retrieval, semen preparation, embryo assessments and transfer, cryopreservation of sperm, eggs, and embryos, and media preparation.

In 2014 Mr. Lo a Master of Science Degree in Clinical Embryology from the University of Leeds in the United Kingdom. Mr. Lo went on to join Yale University’s Department of Obstetrics and Gynecology as Scientific Technician and Associate Research Scientist.