Related Experiment Video
Updated: May 17, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Randomized controlled trial comparing highly purified (HP-hCG) and recombinant hCG (r-hCG) for triggering ovulation
Marina Bellavia1, Christian de Geyter, Isabelle Streuli
1Department of Obstetrics & Gynecology, Reproductive Endocrinology and Infertility, CHUV, Lausanne, Switzerland.
Background:
A randomized controlled trial (RCT) comparing highly purified human Choriogonadotrophin (HP-hCG) and recombinant hCG (r-hCG) both administered subcutaneously for triggering ovulation in controlled ovarian stimulation (COS) for Assisted Reproductive Technology (ART).
Methods:
Multi-centre (n = 4), prospective, controlled, randomized, non-inferiority, parallel group, investigator blind design, including 147 patients. The trial was registered with www.clinicaltrials.gov, using the identifier: NCT00335569. The primary endpoint is the number of oocytes retrieved, while the secondary endpoints include embryo implantation, pregnancy and delivery rates as well as safety parameters.
Results:
The number of retrieved oocytes was not inferior when HP-hCG was used as compared to r-hCG: the mean number was 13.3 (6.8) in HP-hCG and 12.5 (5.8) in the r-hCG group (p = 0.49) with a 95% CI (-1.34, 2.77). Regarding the secondary outcomes, there were also no differences in fertilization rate at 57.3% (467/815) vs. 61.3% (482/787) (p = 0.11), the number of embryos available for transfer and cryopreservation (2PN stage) and implantation, pregnancy and delivery rates. Furthermore, there were no differences in the number and type of adverse events reported. HP-hCG was therefore not inferior to r-hCG.
Conclusions:
HP-hCG and r-hCG are equally efficient and safe for triggering ovulation in ART and, both being administered subcutaneously, equally practical and well tolerated by patients.
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