Dr. Mark F. Severino

Lead Physician

For more than 30 years, Mark Severino, MD, a board-certified and highly-experienced reproductive endocrinologist, has been helping couples achieve their dreams of family. Well-respected for his work and numerous published articles on topics related to infertility and In Vitro Fertilization, Dr. Severino brings a wide breadth of experience to SIRM Las Vegas. He led the efforts to established the fertility program for Aurora Healthcare in Wisconsin and served as faculty at the University of Wisconsin, Madison.  Dr. Severino co-founded the Nevada Fertility Center for Advanced Reproductive Endocrinology and Surgery prior to joining SIRM. He has been voted into the Guide to America’s Top Obstetricians and Gynecologists in Reproductive Endocrinology and Infertility. Read more.

      Zeki Beyhan

Laboratory  Manager, Embryology Laboratory Director

Zeki holds a M.S. & Ph.D. in Endocrinology and Reproductive Physiology (ERP) from the University of Wisconsin-Madison.  He also is a certified Embryology Lab Director(ELD)  and Technical Supervisor(TS-Embryology and Andr

      Briana Ohel


Hello! I’m Briana and I have been an IVF Nurse at Sher Fertility since 2013. The intricate science of this field is fascinating to me and I absolutely love helping people from all over the world build their families. Little did I know that I, too, would struggle with infertility. Thanks to Dr. Severino and my SIRM family, my husband and I now have 11 month old girl/boy twins, Eleanor and Julian. I see myself as a fertility nurse for years to come and hope to help you make this journey a little easier.