Title: De-identified dataset: dual versus GnRH agonist-only trigger in women with polycystic ovary syndrome undergoing GnRH antagonist IVF cycles

De-identified analysis dataset comprising 930 stimulation cycles from patients with polycystic ovary syndrome who underwent GnRH antagonist IVF cycles with a freeze-all strategy between 2018 and 2024 at a single centre. Cycles were triggered either with a GnRH agonist alone or with a GnRH agonist combined with low-dose hCG (dual trigger). The dataset includes demographic, reproductive, stimulation, embryological and clinical outcome variables, including live birth and ovarian hyperstimulation syndrome. All direct identifiers have been removed; patient and cycle identifiers are arbitrary sequential codes. A data dictionary is provided in README_data_dictionary.md. Cycles rather than patients are the unit of analysis; analyses should account for clustering within patient_id.