Pregnancy success rate with daily, low-dose hCG injection similar to vaginal hormonal gel
A daily subcutaneous injection of human chorionic gonadotropin for 2 weeks after an embryo transfer resulted in as many successful pregnancies for women as those who used a vaginal hormonal gel, according to research in Human Reproduction.
In a proof-of-concept study conducted as a three-arm randomized controlled trial, researchers found that women randomly assigned a 14-day, once-daily injection of human chorionic gonadotropin (hCG) found the treatment patient-friendly, as it avoided repeated daily administration of a vaginal progesterone gel, which can cause genital irritation and leakage.
“With this new concept we ‘ push ’ the endogen ous progesterone production from the corpus luteum , instead of administ ering progesterone exogenously,” Peter Humaidan, DMSc, of Aarhus University and the Fertility Clinic at Skive Regional Hospital in Denmark, told Endocrine Today. “We promote the natural production of other factors ... seen in the natural luteal phase — ie, not only progesterone.”
Humaidan and Claus Yding Andersen, of the Juliane Marie Center for Women, Children and Reproduction at Copenhagen University Hospital in Denmark, and colleagues analyzed data from 93 women without polycystic ovary syndrome aged 25 to 40 years undergoing in vitro fertilization (IVF) treatment between 2012 and January 2014. Within the cohort, 31 women (mean age, 31 years) were randomly assigned to group 1; 30 women were assigned to group 2 (mean age, 33 years); and 32 women (mean age, 31 years) served as controls receiving standard care after the transfer of eggs, including a vaginal hormonal gel.
After a gonadotropin-releasing hormone agonist (GnRHa) trigger to stimulate ovulation, women in groups 1 and 2 received daily injections of 125 IU hCG for luteal phase support beginning on either stimulation day 2 (group 1) or day 6 (group 2). Researchers obtained blood samples on the day of ovulation induction, day of oocyte pickup and then again 7 days after oocyte pickup.
Researchers found that women assigned daily hCG injections had significantly higher progesterone levels during the mid-luteal phase when compared with women assigned the hormonal vaginal gel. Average mid-luteal progesterone levels for group 1 were 334 nmol/L; 277 nmol/L for study group 2 and 177 nmol/L for controls. In addition, the daily injection of hCG also prevented increases in the progesterone serum and supra-physiologic steroid levels often seen during the early luteal phase after an hCG trigger, according to researchers.
Pregnancy rates among the three study arms were similar, with nine full-term pregnancies in group 1, 11 full-term pregnancies in group 2 and 11 full-term pregnancies in the control group. Researchers cautioned that the study was too small to reveal significant differences regarding reproductive outcomes.
“ Pregnancy rates, using this new protocol, were as good as when using the golden standard protocol [ vaginal administration of progesterone ] ,” Humaidan said. “ We believe that this protocol will be the future protocol in IVF patients due to the good outcomes and a higher degree of patient satisfaction. ”
Humaidan and colleagues are currently working on a long-acting hCG molecule, he said, in the hopes of developing a protocol of only two injections after the transfer of eggs, instead of a daily subcutaneous injection for 14 days. – by Regina Schaffer
Disclosure: The researchers report no relevant financial disclosures.