Background: Premature progesterone rise (PPR) refers to an increase in serum progesterone (P4) levels on or before the human chorionic gonadotropin (hCG) trigger day. This work aimed to evaluate the impact of serum P4 levels on the day of hCG trigger on the outcomes of intracytoplasmic sperm injection (ICSI) cycles using the gonadotropin-releasing hormone (GnRH) antagonist protocol. Methods: The prospective cohort study was conducted at the Cytogenetics and Endoscopy unit, Obstetrics & Gynaecology Department, Zagazig University, including 150 women having ICSI/fresh-embryo transfer (ET). Each patient had one trial of ICSI/fresh ET cycle. In the study, patients were subjected to controlled ovarian stimulation (COS) using a GnRH antagonist protocol. P4 levels were measured on the hCG trigger day (hCG-P4), and the results were correlated to the outcomes of the ICSI cycle. Results: There was a statistically significant negative correlation between hCG-P4 and the top-quality embryo (TQE) rate. No significant association was found between hCG-P4 level and clinical pregnancy, ongoing pregnancy, or miscarriage. The cutoff for hCG-P4 predicting unsuccessful achievement of clinical pregnancy was ≥ 0.925 (p>0.05). Patients with hCG-P4 level ≥0.925 ng/ml had a significantly lower TQE rate than patients with hCG-P4