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Updated: Jun 17, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Low-dose HCG may improve pregnancy rates and lower OHSS in antagonist cycles: a meta-analysis
I P Kosmas1, K Zikopoulos, I Georgiou
1Centre for Reproductive Medicine, Department of Obstetrics and Gynecology, Ioannina University School of Medicine, Ioannina, Greece. kosmasioannis@gmail.com
Abstract:
Human chorionic gonadotrophin (HCG) may substitute FSH to complete follicular growth in IVF cycles. This may be useful in the prevention of ovarian hyperstimulation syndrome. Relevant studies were identified on Medline. To evaluate outcomes, a meta-analysis of low-dose HCG-supplemented IVF cycles versus non-supplemented ones was performed with data from 435 patients undergoing IVF who were administered low-dose HCG in various agonist and antagonist protocols and from 597 conservatively treated patients who served, as control subjects. Using these published data, a decision analysis evaluated four different management strategies. Effectiveness and economic outcomes were assessed by FSH consumption, clinical pregnancy and incremental cost-effectiveness ratios. Clinical pregnancy and ovarian hyperstimulation were the main outcome measures. Nine trials published in 2002-2007 were included. From the prospective studies, in the gonadotrophin-releasing hormone antagonist group, a trend for significance in clinical pregnancy rate was evident (odds ratio [OR], 1.54; 95% confidence interval [CI], 0.98-2.42). Ovarian hyperstimulation was less significant in the antagonist low-dose HCG protocol compared with the non-supplemented agonist protocol (OR 0.30; 95% CI 0.09-0.96). Less FSH was consumed in the low-dose HCG group but this difference was not statistically significant. Low-dose HCG supplementation may improve pregnancy rates in antagonist protocols. Overall, low-dose HCG-supplemented protocols are a cost-effective strategy.
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