Endometrial infusion of human chorionic gonadotropin at the time of blastocyst embryo transfer does not impact clinical outcomes: a randomized, double-blind, placebo-controlled trial

Fertil Steril. 2014 Dec;102(6):1591-5.e2. doi: 10.1016/j.fertnstert.2014.08.006. Epub 2014 Sep 16.


Objective: To determine whether endometrial hCG infusion at the time of human blastocyst transfer impacts implantation rates.

Design: Randomized double-blinded placebo-controlled trial.

Setting: Academic.

Patient(s): Infertile couples with the female partner less than 43 years old (n = 300) undergoing fresh or frozen ET of one or two blastocysts.

Intervention(s): Patients undergoing ET were randomized into either a treatment or a control group. The treatment group received an infusion of 500 IU of hCG diluted in ET media. The control group received a sham infusion of ET media. Infusions were done using a separate catheter less than 3 minutes before actual ET.

Main outcome measure(s): Sustained implantation rate: ongoing viable gestation (primary outcome) and ongoing pregnancy rate (secondary outcome).

Result(s): A total of 473 blastocysts were transferred into 300 patients. There were no differences between the two groups in sustained implantation rate (48.1% in the hCG group, 44.2% in the control group) or ongoing pregnancy rate (58.8% in the hCG group, 52.0% in the control group).

Conclusion(s): Endometrial infusion of hCG at the time of blastocyst ET does not improve sustained implantation rates.

Clinical trial registration number: NCT01643993.

Keywords: embryo transfer; hCG; implantation rate; intrauterine hCG; pregnancy rate.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Blastocyst
  • Chorionic Gonadotropin / administration & dosage*
  • Double-Blind Method
  • Embryo Implantation*
  • Embryo Transfer*
  • Endometrium
  • Female
  • Freezing
  • Humans
  • Infertility / therapy*
  • Pregnancy
  • Pregnancy Rate


  • Chorionic Gonadotropin

Associated data

  • ClinicalTrials.gov/NCT01643993