biostudies-literatureUnknown6(3)Gao F<h4>Objective</h4>To study whether luteal phase stimulation provides clinical and embryological outcomes comparable to follicular phase stimulation in controlled ovarian hyperstimulation cycles.<h4>Design</h4>Retrospective cohort study.<h4>Subjects</h4>A total of 12,442 patients undergoing 18,062 in vitro fertilization cycles between January 1, 2018, and December 21, 2021, across 6 assisted reproductive technology centers within a large US fertility network.<h4>Exposure</h4>Patients underwent controlled ovarian hyperstimulation using either follicular phase or luteal phase initiation. Cycles involving fresh transfers, day 3 transfers, or poor endometrial receptivity were excluded.<h4>Main outcome measures</h4>The primary outcomes were clinical pregnancy rates and cumulative live birth rateF&S reports289-298https://www.ebi.ac.uk/biostudies/studies/S-EPMC12496433biostudies-literatureComparable Clinical and Embryological Outcomes in Luteal and Follicular Phase Controlled Ovarian Hyperstimulation: A Retrospective Cohort Study.PMC12496433Baxter KMascaros Martinez JMGarrido NGao FKort JWhitehead CBadamjav OfalseComparable Clinical and Embryological Outcomes in Luteal and Follicular Phase Controlled Ovarian Hyperstimulation: A Retrospective Cohort Study.<h4>Objective</h4>To study whether luteal phase stimulation provides clinical and embryological outcomes comparable to follicular phase stimulation in controlled ovarian hyperstimulation cycles.<h4>Design</h4>Retrospective cohort study.<h4>Subjects</h4>A total of 12,442 patients undergoing 18,062 in vitro fertilization cycles between January 1, 2018, and December 21, 2021, across 6 assisted reproductive technology centers within a large US fertility network.<h4>Exposure</h4>Patients underwent controlled ovarian hyperstimulation using either follicular phase or luteal phase initiation. Cycles involving fresh transfers, day 3 transfers, or poor endometrial receptivity were excluded.<h4>Main outcome measures</h4>The primary outcomes were clinical pregnancy rates and cumulative live birth rate2025-01-01T00:00:00Z2025 Sep2026-06-04T03:17:08.073Z2026-06-04T03:06:38.324ZS-EPMC124964334105472410.1016/j.xfre.2025.06.008