GnRH agonist + hCG improves oocyte retrieval in IVF patients
Dual triggering with a gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin (hCG) may increase the number of oocytes among women undergoing in vitro fertilization (IVF), according to a study presented at ESHRE 2018.
This single-centre, prospective double-blind trial consisted of 160 women (mean age 36 years, mean BMI 24 kg/m2) on their first to third IVF cycle attempts. Participants were given hCG alone (10,000 IU and placebo, n=80) or hCG plus a GnRH agonist (dual trigger group; 10,000 IU and 0.5 mg, n=80) 36 hours prior to oocyte retrieval. The baseline and stimulation cycle characteristics were similar between the treatment groups. [ESHRE 2018, abstract O-208]
Compared with women given hCG only, those in the dual trigger group had significantly more oocytes retrieved (12.9 vs 10.6; p=0.02).
Women treated with dual trigger vs hCG also had a significantly higher rate of oocyte recovery (number of oocytes in each follicle, 96.1 percent vs 76.6 percent; p=0.001 [above 10 mm] and 145.1 percent vs 121.8 percent; p=0.03 [above 15 mm]).
A majority, but not all of the oocytes were mature, said study lead author Dr Jigal Haas from the IVF unit at TRIO Fertility Clinic in Toronto, Ontario, Canada.
Compared with those in the hCG only group, women in the dual trigger group had significantly more metaphase II oocytes (10.1 vs 8.6; p=0.04), zygotes (7.9 vs 6.3; p=0.04), embryos (6.6 vs 5.7; p=0.03), and blastocysts (3.7 vs 3.1; p=0.02), as well as top-quality blastocysts (2.5 vs 1.8; p=0.02).
A higher rate of cumulative pregnancy was observed in women who had dual trigger vs hCG treatment (64 percent vs 57 percent), though the difference was not statistically significant due to small sample size.
According to the researchers, the findings were consistent with a previous study which revealed that women treated with co-administration of a GnRH agonist and hCG demonstrated a higher rate of oocyte recovery, fertilization, and top-quality embryos. [Gynecol Endocrinol 2015;31:145-147]
“We think that the increase in the number of mature oocytes may potentially improve the outcome of the IVF cycle,” said Haas, recommending a larger study assessing pregnancy outcomes in women given the dual trigger combination.“We believe that by hCG, we get great results, but by the dual trigger, we can get better results,” Haas noted.