Empty follicle syndrome after GnRH agonist triggering: Is it possible to res- cue with hCG? Two cases and review of the literature

Empty follicle syndrome (EFS) is a rare condition characterized by failure to obtain oocytes despite repeated meticulous aspiration from normally growing ovarian follicles during in vitro fertilization (IVF) cycles. Here in we report two cases of empty follicle syndrome after gonadotropin releasing hormone agonist (GnRHa) triggering for final oocyte maturation due to ovarian hyperstimulation syndrome (OHSS) risk. Neither oocytes nor granulosa cells were recovered in both patients during first oocyte pick up procedure despite developing multiple follicles. The patients were succesfully rescued by retriggering maturation using hCG and only two and one oocytes could be obtained in patient 1 and 2 respectively after 24 hours. The oocytes were mature (MII) and fertilized normally. Fresh transfer of two embryos and frozen thaw transfer of one embryo was applied to patient 1 and patient 2 respectively. Successful pregnancies were achieved in both patients. Management options of EFS in hyperresponder patients triggered with GnRH agonist might be a rescue protocol including retriggering with hCG, freeze the embryos and also a subsequent frozen thaw transfer in order to avoid from OHSS. Fresh transfer could be an option when the embryos could not be frozen however other prevention strategies such as cabergoline and hydoxethylstarch should be considered in these cases.