Borderline form of empty follicle syndrome: is it really an entity?

We report two patients who were administered erroneously 1000 IU HCG instea d of 10 000 IU for ovulation triggering in an assisted reproductive technol ogy (ART) cycle. In one case no oocyte was retrieved from eight mature foll icles after several washing attempts and retrieval day serum beta-HCG level was 21 mIU/ml. As there was no follicle in the other ovary we did not try a rescue protocol. In the other case two immature and one mature oocytes we re retrieved from 15 mature follicles located in both ovaries. Retrieval da y serum beta-HCG level was 12 mIU/ml. ICSI was performed in one mature and two in vitro maturated oocytes and the embryo transfer that was done 72 h a fter the retrieval yielded a healthy singleton pregnancy. Our experience sh ows that a borderline form of EFS may be an entity and it may be possible t o see the formation of periovulatory events and even to obtain a pregnancy in an ART cycle where the ovulation was triggered by 1000 IU HCG. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.