Objective: Conventionally, hCG is used as a 'faux' LH surge to bring final oocyte maturation due to structural similarity with LH. Although GnRH agonists induce a more physiological gonadotropin surge for follicular maturation, they have been associated with luteal phase deficiency. Our aim was to assess whether adding a gonadotropin-releasing hormone agonist (GnRHa) to hCG trigger improves oocyte maturation and the number of high-grade embryos in GnRH antagonist IVF cycles.
Methods: This was a single center, open-labelled, randomized controlled trial including 100 patients between 21-38 years (tubal factor, male factor, unexplained infertility, with normal ovarian reserve) undergoing IVF using the GnRH antagonist protocol. Patients were randomized to receive either the dual trigger (Leuprolide acetate 1mg + rhCG 250µg, n=50) or a single hCG trigger (rhCG 250µg, n=50). Analysis was done by ITT. Independent-t and chi-square tests were used in the comparisons of normally distributed quantitative variables and qualitative variables.
Results: With similar baseline characteristics, the number of MII oocytes (7.82 vs. 5.92, p=0.003) and day-3 grade-1 embryos (4.24 vs. 1.8, p<0.001) and consequently, number of embryos cryopreserved (2.68 vs. 0.94, p<0.001) were significantly higher in the dual trigger group. However, the fertilization (91.82% vs. 88.51%, p=0.184) and clinical pregnancy rates between the two groups (21% vs. 19.6%, p=0.770) were comparable. Serum LH levels 12 hours post trigger were high in the dual trigger group (46.23mIU/ml vs. 0.93mIU/ml, p<0.0001).
Conclusions: This study found that the addition of GnRHa to hCG trigger leads to improved embryological outcomes and the possibility of cryopreserving surplus embryos, thereby increasing cumulative live births.
Keywords: antagonist cycle; dual trigger; single trigger.