Enhancement of embryo developmental potential by a single administration of GnRH agonist at the time of implantation.

BACKGROUND Several reports have shown that inadvertent administration of a GnRH agonist in the luteal phase does not compromise pregnancy. Moreover, some studies suggested that, unexpectedly, the embryo developmental potential is improved in these conditions. This prospective controlled study was designed to test this hypothesis. METHODS In an oocyte donation programme, oocytes from each donor (n = 138) were shared by two recipients, one of whom was given a single dose of a GnRH agonist (0.1 mg triptorelin) 6 days after ICSI, and the other received placebo at the same time. RESULTS Oocyte recipients treated with GnRH agonist 6 days after ICSI had higher implantation (36.9 versus 25.1%), twin pregnancy (16.7 versus 3.6%), twin delivery (13.8 versus 2.2%) and birth (31.1 versus 21.5%) rates and similar miscarriage and abortion rates as compared with the placebo group. CONCLUSIONS GnRH agonist administration at the time of implantation enhances embryo developmental potential, probably by a direct effect on the embryo.