- What REI Certification Actually Is
- Who Certifies and What the Process Looks Like
- The Training Path Behind the Credential
- Written QE and Oral CE: Two Distinct Stages
- The Six Content Domains in Detail
- Subcategory Map: What the Blueprint Names
- What the Published Numbers Do and Do Not Tell You
- Sequencing Your Preparation by Domain
- Frequently Asked Questions
- REI certification is a subspecialty credential in Reproductive Endocrinology & Infertility, issued through the American Board of Obstetrics and Gynecology...
- It has two distinct stages: a written Qualifying Examination (QE) and an oral Certifying Examination (CE).
- The ABOG blueprint organizes content into six domains covering 27 published subcategories, with no percentage weights.
- Fellowship graduates from 2026 onward move from CE eligibility to QE eligibility; earlier graduates keep their prior requirements.
What REI Certification Actually Is
REI certification is the formal board credential for physicians who practice Reproductive Endocrinology & Infertility, the obstetrics and gynecology subspecialty devoted to hormonal disorders of reproduction, infertility evaluation and treatment, assisted reproductive technology, and the genetics and anatomy that shape fertility. It is distinct from general OB/GYN board certification: it recognizes additional fellowship training and demonstrated subspecialty knowledge.
If you landed here looking for a different meaning of the acronym, our explainers on what REI stands for and REI meaning cover the terminology. This article is specifically about the physician subspecialty credential, and for the broader overview of the field itself, see What Is REI?.
Who Certifies and What the Process Looks Like
The certifying body is the American Board of Obstetrics and Gynecology (ABOG). ABOG publishes an exam blueprint for REI on its exam-blueprints resource page, and the current linked document is a four-page PDF that lists six primary categories and 27 subcategories. The written QE is delivered through Pearson VUE, while the CE is the oral examination stage.
Two practical caveats matter for anyone planning around logistics:
- The blueprint is common to both stages. It does not assign separate QE and CE coverage or weights, so you cannot treat it as a stage-by-stage syllabus.
- Numeric logistics live in the bulletins. Registration windows, fees, and similar stage-specific numbers are governed by the applicable current QE or CE bulletin, not by the blueprint. For the cost side, see our REI certification cost breakdown, and for scheduling see REI exam dates and deadlines.
ABOG also expects certified physicians to participate in continuing certification to remain certified, so the credential is an ongoing commitment rather than a one-time event.
The Training Path Behind the Credential
Professional-society guidance from ASRM (its 2025 scope-of-practice statement for the REI subspecialist) describes the pipeline: medical school, then a four-year obstetrics and gynecology residency, then a three-year REI fellowship. That summary describes training context; it is not an exam blueprint, and the formal eligibility rules are set by ABOG. Our REI requirements guide walks through eligibility and prerequisites in more depth, and REI training covers the fellowship experience itself.
A Recent Change Worth Knowing
According to an ABOG update presented at the 2026 SMFM Program Directors Meeting, the thesis requirement moves from CE eligibility to QE eligibility for fellowship graduates from 2026 onward. Graduates from earlier years retain the requirements that applied to them. If you are a fellow or recent graduate, confirm which cohort rules apply to you directly with ABOG rather than relying on secondhand summaries.
Written QE and Oral CE: Two Distinct Stages
The structure of REI certification is deliberately two-part, and the stages test different things.
| Feature | Qualifying Examination (QE) | Certifying Examination (CE) |
|---|---|---|
| Format | Written, delivered through Pearson VUE | Oral |
| What it emphasizes | Breadth of subspecialty knowledge across the blueprint | Clinical reasoning, judgment, and defense of decisions |
| Blueprint coverage | Common REI blueprint; no separate allocation published | Common REI blueprint; no separate allocation published |
| 2025 first-time pass rate (ABOG report) | 100% (N=55) | 94.7% (N=57) |
| 2026 date cited by ABOG | July 20 | April 13-17 |
Those 2026 dates are historical reference points from the ABOG presentation, not promises about future booking. The same presentation's repeat-taker and overall cohort counts were internally inconsistent, so no reconciled overall pass rate is asserted here. For a fuller discussion of what the numbers can and cannot support, see REI pass rate: what the data shows, and for scoring questions see REI passing score.
The Six Content Domains in Detail
The blueprint's six primary clinical categories are the backbone of preparation. ABOG does not publish percentage weights, so resist any source that claims precise domain percentages. For a longer treatment of each area, read REI exam domains: a complete guide to all six content areas.
Domain 1: Foundational Reproductive Endocrinology
The scientific bedrock: how hormones are built, how they act, how drugs modulate them, and how laboratories measure them.
- Hormone structure and function
- Basic pharmacology of agents used in reproductive medicine
- Laboratory assays, including what they measure and how results mislead
Domain 2: Reproductive Endocrine Function and Disease
Physiology across the lifespan and the disorders that disrupt it.
- Reproductive physiology from development through the menopausal transition
- Neuroendocrine disorders and thyroid disorders
- Endometrial physiology and abnormal uterine bleeding
- Ovarian and adrenal disorders, both idiopathic and iatrogenic
Domain 3: Conception and Pregnancy: Physiology and Pathology
From gametes to early gestation.
- Gamete biology and early embryo development
- Endocrinology of pregnancy and early pregnancy
- Recurrent pregnancy loss
Domain 4: Fertility and Infertility
The clinical heart of the specialty, spanning evaluation and treatment.
- Female fertility and infertility; male infertility
- Fertility treatment special considerations
- Assisted reproductive technology (ART) techniques
- Fertility preservation
Domain 5: Anatomic Reproductive Disorders
Structural and pelvic conditions that affect fertility and reproductive health.
- Pelvic adhesive disease, endometriosis, and adenomyosis
- Congenital anomalies of the reproductive tract
- Asherman syndrome, leiomyomas, and endometrial polyps
Domain 6: Reproductive Genetics
Both understanding and applying genetic testing.
- Understanding of genetic testing and screening
- Application of genetic screening and testing to patient care
Subcategory Map: What the Blueprint Names
Below is the complete published list of 27 subcategories, grouped by the six domains. Use it as a checklist when auditing your own gaps; our REI cheat sheet condenses must-know facts against this same structure.
| Domain | Published Subcategories |
|---|---|
| 1. Foundational Reproductive Endocrinology | REI1.1 Hormone Structure and Function; REI1.2 Basic Pharmacology; REI1.3 Laboratory Assays |
| 2. Reproductive Endocrine Function and Disease | REI2.1 Reproductive Physiology Across the Lifespan; REI2.2 Neuroendocrine Disorders; REI2.3 Thyroid Disorders; REI2.4 Endometrial Physiology and Abnormal Uterine Bleeding; REI2.5 Ovarian and Adrenal Disorders (Idiopathic and Iatrogenic) |
| 3. Conception and Pregnancy: Physiology and Pathology | REI3.1 Gamete Biology; REI3.2 Early Embryo Development; REI3.3 Endocrinology of Pregnancy; REI3.4 Early Pregnancy; REI3.5 Recurrent Pregnancy Loss |
| 4. Fertility and Infertility | REI4.1 Female Fertility and Infertility; REI4.2 Male Infertility; REI4.3 Fertility Treatment: Special Considerations; REI4.4 Assisted Reproductive Technology (ART) Techniques; REI4.5 Fertility Preservation |
| 5. Anatomic Reproductive Disorders | REI5.1 Pelvic Adhesive Disease; REI5.2 Endometriosis; REI5.3 Adenomyosis; REI5.4 Congenital Anomalies of the Reproductive Tract; REI5.5 Asherman Syndrome; REI5.6 Leiomyomas; REI5.7 Endometrial Polyps |
| 6. Reproductive Genetics | REI6.1 Understanding of Genetic Testing and Screening; REI6.2 Application of Genetic Screening and Testing to Patient Care |
What the Published Numbers Do and Do Not Tell You
It is tempting to read a 100% first-time QE rate and a 94.7% first-time CE rate as proof that the exams are easy. That inference is shaky. The candidate pool is a small, highly selected group who have already completed residency and a three-year fellowship, and the numbers come from a single year. For a calibrated view of difficulty, see how hard the REI exam is.
Equally important is what the blueprint does not say. It prints no percentage weights, no separate QE versus CE allocation, and no formal revision or effective date, even though the file URL contains "2026." Any practice-question mix, including the one on our own REI practice test site, is an editorial allocation designed to help you cover the blueprint, not an official statement of coverage.
Is the Credential Worth the Effort?
For physicians who intend to practice as REI subspecialists, board certification is the standard professional marker, and employers such as fertility centers, academic departments, and hospital-based reproductive programs generally look for it. We analyze the career and financial side in the REI salary guide, whether REI certification is worth it, and REI jobs. We deliberately avoid quoting earnings figures here because none are established in the certification materials.
Sequencing Your Preparation by Domain
Because the blueprint has no weights, sequence by dependency rather than by guessed percentages. Foundational material underpins nearly everything else, genetics threads through embryology and recurrent loss, and anatomic disorders reward visual and procedural recall. The sketch below is an example ordering, not an official schedule; our REI study guide expands on it.
Domain 1 and Domain 2 Foundations
- Hormone structure, pharmacology, and assay interpretation first, since later domains assume them
- Neuroendocrine, thyroid, and ovarian/adrenal disorders, including iatrogenic causes
Domain 3 and Domain 6 Together
- Gamete biology, early embryo development, and early pregnancy endocrinology
- Pair recurrent pregnancy loss with genetic testing and screening so the two reinforce each other
Domain 4 and Domain 5 Clinical Integration
- Female and male infertility, ART techniques, and fertility preservation
- Endometriosis, adenomyosis, Asherman syndrome, leiomyomas, polyps, and tract anomalies
Mixed Review and Oral Rehearsal
- Interleave all six domains in timed question blocks
- Practice verbalizing your reasoning aloud for the CE stage
Key Takeaway
Treat the 27 subcategories as your audit list. After each study block, mark which subcategories you can explain aloud without notes; the oral CE rewards that ability, and the written QE rewards the recall beneath it.
Frequently Asked Questions
It is the subspecialty board credential in Reproductive Endocrinology & Infertility, issued through the American Board of Obstetrics and Gynecology (ABOG) after fellowship training and successful completion of a written Qualifying Examination and an oral Certifying Examination. You can also browse our REI certification overview and related explainer for additional context.
No. The QE is a written exam delivered through Pearson VUE, and the CE is a separate oral exam. ABOG's common REI blueprint does not assign different coverage or weights to each stage.
No. The current blueprint lists six primary categories and 27 subcategories without percentage weights, so any specific percentage you see elsewhere is editorial or unsupported.
An ABOG update reports that the thesis requirement moves from CE eligibility to QE eligibility for fellowship graduates from 2026 onward. Earlier graduates retain their prior requirements, so verify your own situation with ABOG.
Our REI practice tests are organized around the six blueprint domains. Remember that question allocation there is editorial, designed to cover the published subcategories rather than mirror an official weighting.