What is a Reproductive Endocrinologist?

Medically Reviewed by Traci C. Johnson, MD on November 25, 2022
3 min read

An endocrinologist is a doctor who specializes in the endocrine system. This network of glands inside your body creates hormones that help cells talk to each other. The endocrine system is varied and complex, but one important job it has is to help with reproduction. 

A reproductive endocrinologist, sometimes referred to as an RE, is an obstetrician/gynecologist (OB/GYN) physician who diagnoses and treats endocrine disorders that are either directly or indirectly related to reproduction. They largely deal with issues related to infertility, when you’re unable to get pregnant after one year of unprotected sex.

Many people deal with infertility. In fact, up to 15% of couples are infertile, and the issue is just as common among men as it is among women. 

Reproductive endocrinologists may use surgery, medicine, or procedures to treat infertility. Before they come up with a treatment plan, they must find the source of the problem. To do this, they might: 

  • Check for blood sugar and thyroid abnormalities 
  • Run a semen test
  • Order an X-ray of the uterus and fallopian tubes to look for problems
  • Do an ovarian reserve fertility test to measure the level of various hormones related to reproduction, such as:
    • Follicle-stimulating hormone
    • Estradiol
    • Anti-Müllerian hormone

Based on the results of these tests, reproductive endocrinologists are better able to make an accurate diagnosis. They may then prescribe medicine or recommend procedures like:

  • Laparoscopy, a minimally invasive surgery that uses a tiny camera to let your doctor see inside your body
  • Hysteroscopy, a procedure using a small camera that lets the doctor see images of your cervix and uterus from inside through the vagina
  • Abdominal myomectomy, surgery to remove uterine fibroids

Reproductive endocrinologists also perform various infertility treatments, including:

  • Intrauterine insemination (IUI): Purifying one partner’s sperm sample and placing it into the other’s uterus.
  • In vitro fertilization (IVF): Fertilizing one partner’s egg with the other's sperm in a laboratory and then transferring the best embryo(s) to the mother or surrogate's uterus. 

One full cycle of IVF takes 3 weeks or longer. But it’s the most effective form of assisted reproductive technology to date. Since its introduction in the U.S. in 1981, this procedure and techniques like it have resulted in over 200,000 babies. 

The path to becoming a reproductive endocrinologist is a long one. First, you need a bachelor's degree, usually in a science-based field of study. 

Like all other physicians, you must then pass the Medical College Admissions Test (MCAT) to get into medical school. Then you’ll attend and graduate from a four-year medical school program.

You’ll then take part in a residency program and get certified as an OB/GYN through the American Board of Obstetrics and Gynecology. 

After completing a specialized fellowship in reproductive endocrinology and infertility (REI) after residency, you can take a written and oral exam to become board certified as a reproductive endocrinologist.

You should consider seeing a reproductive endocrinologist if you’re having trouble getting pregnant. As a general guideline, if you’re under 35 and want to conceive a child, you should spend a year trying before you see a reproductive endocrinologist. If you’re over 35, you should try for at least 6 months. 

However, you may want to book an appointment with a reproductive endocrinologist if you have any of the following issues: 

  • Irregular, absent, or painful menstrual periods 
  • One or more miscarriages
  • Treatment(s) that may affect your fertility
  • Endometriosis symptoms or diagnosis
  • Polycystic ovary syndrome (PCOS) symptoms or diagnosis

If you want to get someone pregnant, you should consider seeing a reproductive endocrinologist after a year of regular, unprotected sex or if you have a history of any of the following: 

  • Problems with sexual function
  • Pain, swelling, or a lump in the testicle area
  • Abnormal breast growth 
  • A lower than normal sperm count 

Reproductive endocrinologists are an excellent resource to help you better understand your fertility journey and to provide medical interventions for pregnancy when appropriate.