JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):49
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263588

P-37. Comparative Analysis of Dual Trigger (GnRH-a + hCG) Versus hCG Alone for Final Follicular Maturation Induction

Drielly dos Reis Franzoi¹, Ana Clara Souza Marcolongo da Silva¹, Beatriz Rodrigues da Silva¹, Renato Borges Tesser¹, Rodrigo Alessandro Riemma Vela¹

¹Centro Universitário São Camilo - São Paulo - SP - Brasil

Objective: To compare the efficacy of dual trigger (GnRH-a + hCG) versus hCG alone in inducing final follicular maturation in controlled ovarian stimulation cycles, focusing on laboratory outcomes related to oocyte maturation.
Methods: An integrative review was conducted to address the research question: “In women undergoing controlled ovarian stimulation, does dual trigger (GnRH-a + hCG) lead to better laboratory outcomes in oocyte maturation rates compared with hCG alone?” In July 2025, a literature search was performed in MEDLINE via the Virtual Health Library (VHL) and PubMed, and in LILACS via VHL. The main DeCS/MeSH descriptors were “in vitro fertilization,” “dual trigger,” and “oocyte maturation,” combined using Boolean operators (AND/OR) and adapted for each database. Search limits included publication date (last 5 years), study type (observational clinical trials, randomized clinical trials, reviews, and systematic reviews), and full-text availability. Inclusion criteria followed the PECO framework (P: women undergoing controlled ovarian stimulation for IVF; E: dual trigger (GnRH-a + hCG); C: trigger with hCG alone; O: oocyte maturation rate, fertilization rate, number of viable embryos, blastocyst rate, and other related laboratory outcomes. Studies unrelated to the topic or unavailable in full text were excluded.
Results: The search strategy identified 71 articles, of which 19 met the eligibility criteria and were included in the review. Across the selected studies comparing dual trigger with hCG alone in ovarian stimulation protocols, a consistent trend toward an increased mean number of retrieved oocytes and higher oocyte maturation rates was observed in the dual trigger group. Mean oocyte retrieval ranged from approximately 3.6 to 12.5 in the dual trigger group versus 2.3 to 11.9 with hCG alone. Maturation rates (MII) frequently exceeded 80% in the dual trigger group, compared with 70–78% in the hCG-only group. Subsequent laboratory outcomes showed a slight yet consistent improvement in fertilization and embryo development with dual trigger. The mean fertilization rate was 91.8% in the dual trigger group versus 88.5% in the control group (p=0.184). The mean number of two-pronuclear (2PN) embryos was higher in the dual trigger group (7.18±2.99) than in the control group (5.24±2.74). On day 3 (D3), embryo count averaged 6.6±3.2 for dual trigger versus 4.7±2.7 for hCG alone. By day 5 (D5), corresponding to blastocyst formation, the averages were 3.8±2.2 and 2.6±1.8, respectively. No consistent evidence was found for increased clinical pregnancy or live birth rates, suggesting that laboratory improvements may not always translate into significant clinical gains. However, some studies reported reproductive advantages in fresh cycles, potentially associated with improved endometrium-embryo synchrony and greater oocyte competence. These effects were not observed in frozen cycles, indicating that part of the benefit may be linked to endometrial receptivity.
Conclusion: Dual trigger (GnRH-a + hCG) demonstrated superior performance compared with hCG alone in the evaluated laboratory outcomes, including higher mean oocyte yield, improved maturation rates, and modest but consistent improvements in fertilization rates, 2PN embryo count, and embryo development on D3 and D5. Although these laboratory advantages did not consistently result in higher clinical pregnancy or live birth rates, evidence suggests potential benefits in fresh cycles, possibly due to better endometrium–embryo synchrony and enhanced oocyte competence. These findings highlight the promise of dual trigger as a targeted strategy in specific clinical contexts and underscore the need for further large-scale studies to validate its broader clinical applicability.