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Updated: Nov 19, 2025

OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery
Published on: May 9, 2021
GnRH agonist in association with hCG versus hCG alone for final oocyte maturation triggering in GnRH antagonist
Condesmar M de Oliveira1, Carlos A M de Oliveira1, Larissa L Fonseca1
1Núcleo Santista de Reprodução Humana, Santos - SP, Brazil.
Objective:
To analyze gonadotropin-releasing hormone (GnRH) agonist in association with human chorionic gonadotropin (hCG) (dual triggering) versus hCG alone (conventional triggering) for final oocyte maturation triggering in GnRH antagonist cycles in an unselected population of Brazilian women.
Methods:
This prospective case-control study involved 114 patients referred to autologous in vitro fertilization treatment between February 2018 and August 2019, recruited regardless of age, infertility factor or number of cycles. The patients were randomly allocated into two groups according to oocyte maturation triggering approach: group A (n = 48) - hCG only; and group B (n = 66) - hCG plus GnRH agonist. The main outcomes measured were the number of total and metaphase II (MII) oocytes retrieved.
Results:
The groups were homogenous in terms of age. There were no moderate or severe ovarian hyperstimulation syndrome events. There were no statistical differences concerning total or MII oocytes retrieved between the groups (p > 0.05). The MII/total oocyte rate was 70.9% in group A, and 74.5% in group B (p = 0.679). There was no oocyte retrieved in 2/48 patients (4.16%) in group A, 1/66 (1.5%) in group B. There were no MII oocytes in 4/48 patients (8.3%) in group A, and 2/66 (3%) in group B. Age was directly correlated to the number of total and MII oocytes retrieved (p < 0.05).
Conclusions:
Dual triggering was equivalent to conventional hCH triggering in terms of the number of total and MII oocytes retrieved in the general population. Further studies are necessary to ascertain dual triggering indication in selected groups of women.
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