Continuing the debate on empty follicle syndrome: can it be associated with normal bioavailability of beta-human chorionic gonadotrophin on the day of oocyte recovery?

This paper describes our experience with four ovarian stimulation in-vitro fertilization (IVF) cycles in which we failed to retrieve oocytes despite normal bioavailability of beta-human chorionic gonadotrophin (beta-HCG) in patients' blood 35 h after HCG administration. In three cases, the oocyte recovery procedure was interrupted, a second dose of HCG was administered and 24 h later mature oocytes were collected from two of the patients. In the first case, the three metaphase II oocytes collected fertilized after intracytoplasmic sperm injection (ICSI) and two cleaved grade three embryos were transferred but pregnancy did not ensue. In the second case, six out of eight metaphase II oocytes fertilized and cleaved following ICSI, leading to transfer of one grade two and two grade three embryos. This resulted in a clinical pregnancy which at the time of this report is ongoing. A similar rescue protocol was used for the third case who had empty follicle syndrome (EFS) in her previous treatment cycle but only cumulus-corona complexes were aspirated. Five additional patients who had EFS before instituting pregnancy diagnostic test screening have had further treatment cycles in which oocytes were collected but pregnancy did not ensue. We conclude that normal bioavailability of beta-HCG on the day of oocyte recovery does not exclude the diagnosis of EFS. EFS does not predict a reduced fertility potential in future cycles, although it may recur due to a biological abnormality in the availability of mature oocytes that are retrievable. In such patients, oocyte donation may offer the chance of achieving a pregnancy.