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Updated: Oct 2, 2026

OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery
Published on: May 9, 2021
"Advanced" versus Conventional Trigger results in comparable clinical outcomes in In Vitro Fertilization Cycles
Objectives:
IVF cycle monitoring involves frequent ultrasound and serum hormone measurement until the day of trigger. Alternatively, given known growth trajectory, folliclular maturity can often be anticipated with scheduled trigger (advanced trigger [AT]) obviating the need for frequent monitoring. Thus, we evaluated the impact of AT compared to conventional trigger (CT) on IVF cycle outcomes.
Design:
Retrospective analysis of IVF cycles progressing to trigger and retrieval between 2020-2023. 1351 were included in the analysis. CT was applied in 447 cycles (33.1%) and an AT in 904 cycles (66.9%); specifically, one (-1; 496 (54.9%)), two (-2; 337 (37.3%)), three (-3; 66 (7.3%)), and four (-4; 5 (0.5%)) days prior to the anticipated trigger. Patients/Materials, Setting, Methods: Infertile patients undergoing IVF in either a government owned public clinic or a university based academic fertility center. Those managed by CT were compared to those whose last monitoring was done at least one day prior to the trigger (AT). Data was collected for baseline, emrbyology and clinical outcomes from the medical files. The primary outcome was cumulative live birth rate (cLBR). Secondary outcomes included embryology outcomes and complications. Outcomes were compared using t-test, chi-square test, and ANOVA. Univariate and multiple logistic regression was applied to examine associations of cLBR with AT or CT.
Results:
No differences in embryology outcomes were observed. With respect to clinical outcomes, in the crude analysis, cCPR (44.7% vs 36.2%, p=0.002) and cLBR (40.7% vs 33.2%, p<0.001) were significantly greater in those undergoing CT vs AT. After controlling for confounding variables including age, diagnosis, 2pn/M2 oocytes, multiple regression analysis suggested that cLBR was comparable regardless of using CT or AT (1.17; 95% CI: 0.8-1.72, p=0.41). Adverse events occurred infrequently with no association to trigger type.
Limitations:
Retrospective anaylsis with potentially unmeasured confounders. Data on costs were not collected. The inclusion of 2 centers only could limit external validity.
Conclusion:
This study suggests that an AT does not appear to negatively impact IVF outcomes, suggesting that this may represent an option to improve clinic efficiency while maintinaing IVF success. Our results suggest that AT can be an alternative to CT and should be considerd when patient contact needs to be limited or when clinic visit logistics should interfere with treatment start.
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