REI Resident Fellow Information

Reproductive Endocrinology and Infertility

Reproductive Endocrinology and Infertility (REI) is a subspecialty within Obstetrics and Gynecology which requires an additional 3 year subspecialty fellowship. During that period of time, trainees focus on mastering the diagnosis and treatment of endocrine disorders related to the human reproductive system. Additionally, REIs focus on the diagnosis and treatment of infertility utilizing an array of assisted reproductive technologies.

REI physicians are referral sources for disorders of steroidogenesis, sexual development, puberty, menstruation, hirsutism/PCOS, menopause, hormone replacement therapy, thyroid/adrenal function and reproduction, recurrent pregnancy loss, and male/female fertility, among other things. Many also specialize in the genetics of reproduction and inherited disorders, laboratory science, and molecular biology.

REI Educational Resources for OB/GYN Residents

Understanding reproductive biology is imperative for all OB/GYNs. A firm grasp of the fundamentals for many topics under the purview of REIs will ensure a thoughtful approach to many disorders in general gynecology and in the initial work-up and treatment of the infertile couple. The following may serve as educational resources during residency:

  1. Reproductive Endocrinology and Infertility PROLOG. After studying this unit in the PROLOG series, you should be able to establish differential diagnoses and screen with appropriate diagnostic tests for specific conditions in gynecology and infertility.
  2. ASRM airLearning. This resource includes lectures (approximately 1 hour) on topics including Pediatric Gynecology, Precocious Puberty, Developmental Disorders, Delayed Puberty, Amenorrhea, Hirsutism, Infertility Evaluation, PCOS, and many more!
  3. is another excellent source for information about reproductive, medical and pediatric endocrinology. Many of the available chapters have been written by leaders in the field of REI.

Fellowship Training in REI

Whether you are seeking a career in basic sciences, clinical research, or the practice of Reproductive Endocrinology and Infertility, you will find a fellowship to meet your particular needs and interests. All fellowships are standardized to include 18 months of clinical education and 18 months of research education and experience.

Application to all REI Fellowship programs is made through the Electronic Residency Application Service (ERAS) via the Association of American Medical Colleges (AAMC) website at the below link.

Deadline information will be found under the ERAS for Applicants tab followed by Training in a Residency or Fellowship tab.  As in the past, the matching program is coordinated via the National Resident Matching Program (NRMP) and fellowship applicants must register with NRMP to participate in the Fellowship match. More information about the REI Match process rules may be found at Rules and Requirements for Participating Programs.

American Medical Colleges (AAMC)

REI Certification Requirements

  • Completion of an ABOG approved REI Fellowship Training Program
  • Passing both written and oral examinations in General Ob/Gyn.
  • Thesis accepted by ABOG at the time of the oral REI examination
  • Passing both written and oral examinations in REI