Cruise Control Study: Simplification of IVF Monitoring in a Mixed Protocol Using a Novel Dosing Regimen

Objective To identify the subset of the in vitro fertilization (IVF) population suitable for minimal monitoring by implementing a novel dosing regimen. Methods A retrospective study conducted between April 2021 and August 2022. Eligible participants were aged 18 or older, had undergone IVF stimulation using an antagonist protocol, and were prescribed a combination of follitropin delta and human menopausal gonadotropin. The dosage was either based on a patient-specific dosing regimen developed by the ovo clinic utilizing weight and AMH levels (Group 1, n=356) or determined through clinical evaluation by the physician (Group 2, n=358). On day 6, ultrasound and serum hormone analyses were performed, with adjustments made solely to the menotropin dosage in necessary. Results The study enrolled a total of 714 patients. In Group 1, 80,3% of patients were stimulated at maximal doses compared to 14,5% in Group 2. No cases of moderate or severe cases of ovarian hyperstimulation syndrome (OHSS) were recorded. The frequency of dose adjustments before day 10 was minimal. Patients treated with non-maximal doses according to the dosing regimen showed significantly fewer adjustments on day 6 compared to those treated according to physician’s assessment (24.6% versus 46.9%, p<0.001). Among this subgroup, OHSS risk was observed in 30.4% of cases. Conclusion Our innovative dosing regimen suggests that initial monitoring on day 10 would suffice for IVF patients with low ovarian reserve undergoing maximal stimulation. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial NCT05737979 ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study was approved by Veritas IRB, an independent research ethics committee. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes * AI : Artificial Intelligence AMH : Anti-Mullerian Hormone ANOVA : Analysis of Variance FSH : Follicle Stimulating Hormone GnRH : Gonadotropin-Releasing Hormone hCG : Human Chorionic Gonadotropin HP-hMG : Highly Purified Human Gonadotropins IU : International Unit IVF : In Vitro Fertilization LH : Luteinizing Hormone PCOS : Polycystic Ovary Syndrome PGT-A : Preimplantation Genetic Testing for Aneuploidy OHSS : Ovarian Hyperstimulation Syndrome