Reproductive endocrinology and infertility (REI) is a surgical subspecialty of obstetrics and gynecology that trains physicians in reproductive medicine addressing hormonal functioning as it pertains to reproduction as well as the issue of infertility. While most REI specialists primarily focus on the treatment of infertility, reproductive endocrinologists are trained to also test and treat hormonal dysfunctions in females and males outside infertility. Reproductive endocrinologists have specialty training (residency) in obstetrics and gynecology (ob-gyn) before they undergo sub-specialty training (fellowship) in REI.
In a number of countries, the pathway to become a subspecialist in REI is regulated. Thus, in the United States, for instance, the American Board of Obstetrics and Gynecology (ABOG) and American Osteopathic Board of Obstetrics and Gynecology set the standards for subspecialists to become certified. After four years of training in Obstetrics and Gynecology, a three-year approved fellowship needs to be successfully completed. Then, to become board certified in reproductive endocrinology and infertility, one must first complete board certification in obstetrics and gynecology (written and oral exams), and then certify in reproductive endocrinology and infertility (written and oral exams).
In the United States, fellowship in reproductive endocrinology and infertility usually takes 3 years, and is offered in 40 centers across the country as of 2013.
In the European Union, the European Board and College of Obstetrics and Gynaecology (EBCOG) has accreditation centers for a subspecialist training program in reproductive medicine at 4 centers across the EU as of 2012.
Reproductive endocrinologists Certified by ACOG often belong to a specific medical society named Society for Reproductive Endocrinology and Infertility (SREI). As a condition of full membership, medical practitioners must be ACOG-certified in the reproductive endocrinology and infertility subspecialty.
Also, many academic journals in obstetrics and gynaecology dedicate many articles to reproductive endocrinology and infertility.