Reproductive Endocrinology Handbook 2026: A Clinical Textbook Covering Phenotype-Driven Cycle Management, IVF Laboratory Practice, and Ovulation Induction for REI Fellows

Recognize the Phenotype, Choose the Protocol, Manage the Cycle

Built for the REI fellow and the practicing reproductive endocrinologist who must match the right stimulation strategy to the specific patient phenotype, this reference builds clinical decisions on the HPO axis, the two-cell two-gonadotropin model, and the biology of ovarian reserve. Every chapter carries The Reproductive Phenotype Playbook — a five-part callout naming the phenotype, its signature, the definitive decision, the trap-look-alikes, and the evidence-based anchor — consolidated in the Master Phenotype Playbook Atlas at the back. Annotated ultrasounds, decision algorithms rendered as numbered prose, and phenotype-driven Playbook callouts turn dense reproductive physiology into decisions defensible at the retrieval and the transfer.

What This Book Puts in Your Hands

• Interpret ovarian reserve — AMH, AFC, and Day-3 FSH concordance patterns that separate occult diminished reserve from normal aging and familial early menopause with FMR1 CGG-repeat implications.

• Select the COS protocol — antagonist, long agonist, PPOS, DuoStim, and random-start options matched to the specific patient with individualized start dose.

• Prevent severe OHSS — the antagonist + GnRH agonist trigger + freeze-all triad applied to the predicted hyperresponder before the first injection.

• Read the endometrioma decision — the reserve-versus-symptom trade-off calibrated to age, cyst size, and IVF timeline.

• Interpret PGT results — euploid, mosaic percentage categories, and PGT-M workflow with genetic counseling integration .

• Work up RPL and RIF — systematic four-domain assessment across genetic, anatomic, endocrine, and immunologic contributors with confirmed-APS aspirin plus LMWH management.

• Coordinate urgent oncofertility — random-start antagonist stimulation completed in 2-3 weeks before chemotherapy initiation.

• Navigate third-party reproduction — donor gametes, gestational carrier arrangements, and the reciprocal-IVF pathway for the same-sex female couple.

Open it before your next stimulation cycle — the decisions every REI patient depends on, in one reference.