Effect of hCG on Receptivity of the Human Endometrium
Status:
Completed
Trial end date:
2016-03-01
Target enrollment:
Participant gender:
Summary
Worldwide, 1 in 12 couples experience difficulty in getting pregnant and seek the help of
assisted reproductive technologies (ART) such as in vitro fertilization (IVF-egg is
fertilized by sperm outside the body), ovarian stimulation (medications are used to stimulate
egg development) and intra-cytoplasmic injection (ICSI-single sperm is injected directly into
the egg).
Regardless of the ART procedure being performed, the newly fertilized embryo must still
implant into the mothers endometrium (inner lining of uterus). This implantation process in
humans is surprisingly inefficient and accounts for up to 50% of ART failures. Intrauterine
infusion of hCG prior to embryo transfer has recently been shown to increase pregnancy rates
but the cellular mechanism for this increase is unknown.
Successful implantation requires the newly fertilized embryo and the endometrium develop in a
synchronized manner. This coordinated development is accomplished, in part, by proteins
secreted by the embryo which circulate throughout the maternal bloodstream and alert the
maternal body organs (i.e. ovary, endometrium, breast, ect) that fertilization has occurred.
One of the earliest of these secreted proteins is human chorionic gonadotropin (hCG), which
is the molecule detected in over-the-counter pregnancy tests. From previous studies, we know
that hCG production by the embryo alerts the ovary to continue producing progesterone, a
hormone required for pregnancy. However, very little is known about the direct effect of hCG
on the endometrium during early pregnancy in humans.
Using animal models, hCG has been shown to induce specific changes in the endometrium,
suggesting that embryo-derived hCG may be "priming" the endometrium in anticipation of
implantation. The goal of this research study is to examine the direct effect of hCG on the
human endometrium and see if this "priming effect" is also present in humans. Findings from
this research may reveal whether pre-treatment with hCG can enhance ART outcomes, especially
pregnancy rates.