The Role of Hysteroscopy in Reproductive Medicine and Subfertility: A Critical Narrative Review.

Background and Objectives: Hysteroscopy permits direct assessment and treatment of the uterine cavity, but diagnostic yield does not necessarily translate into improved fertility. This narrative review examines its role in subfertility and reproductive medicine. Materials and Methods: The original literature search covered PubMed/MEDLINE, Scopus and the Cochrane Library through February 2026. Targeted checks during revision added the 2026 chronic endometritis consensus and the full CERM trial report; these updates do not represent a new comprehensive search. Evidence was interpreted by study design, population, outcome and precision, without formal risk-of-bias assessment or meta-analysis. Results: Large randomised trials do not support routine hysteroscopy before first IVF or after repeated IVF failure when ultrasonography is normal. Polypectomy has evidence of improved pregnancy rates in women planning IUI, although spontaneous pregnancies contributed to that result and live-birth benefit remains uncertain. Hysteroscopic myomectomy may improve clinical pregnancy in women with cavity-distorting fibroids; evidence for live birth is less secure. Adhesiolysis restores cavity anatomy, but reproductive estimates largely derive from observational series. The small TRUST trial did not demonstrate a live-birth advantage from septum resection and cannot establish equivalence. Hysteroscopy may guide biopsy for chronic endometritis but does not replace histological assessment. CERM found no improvement with doxycycline in its composite of cumulative live births and ongoing pregnancies at ≥24 weeks among women with recurrent miscarriage and CD138-defined endometritis. Fertility-sparing endometrial cancer treatment requires oncological selection, progestin therapy and histological surveillance. Conclusions: Hysteroscopy should address a defined diagnostic or therapeutic question. Decisions should distinguish spontaneous conception, IUI and IVF/ICSI and acknowledge uncertainty in live-birth outcomes.