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P-302 ATTEMPT TO REDUCE MULTIPLE PREGNANCIES IN ART IN THREE STAGES SINCE 2001. K. Kyono, K. Sasaki, S. Kumagai, C. Nishinaka, Y. Nakajo, H. Uto. Lady’s Clinic Kyono, Miyagi, Japan. OBJECTIVE: Multiple gestations are very risky for the mother, children, and their medical caretaker. Ideal ART is to make one healthy baby from one transferred embryo. From 2001 to 2005 we attempted to determine which embryo transfer protocol would best reduce the number of multiple pregnancies and still maintain an acceptable pregnancy rate. DESIGN: Prospective study at private clinic. MATERIALS AND METHODS: We tried to decrease the number of transferred embryos from 2001 to 2005. During this time, fresh embryo transfer (FET) cycles were 321, 339, 328, 362, 314 per year and frozenthawed embryo transfer (FTET) cycles were 124, 111, 142, 181, 215 per year. First step; in January 2002 we decreased the transferred embryos from three to two by any possibility in the patients under 40 years old. Second step; in July 2003 we again decreased the number of transferred embryos from three to two in all patients under the age of 38 years old and under two previous cycles. Third step; we again decreased the number of transferred embryos to only one in all patients under the age of 35 and under two previous cycles in January 2005. We analysed the data of 2001 as control. Chi-square was used as statistical analysis. RESULTS: FET; The three embryo transfer rate significantly decreased to 40.6%, 12.8%, 3.8% respectively in the three steps compared to control (59.5%).The two embryo transfer rate increased to 37.7% and 66.2% in the first and the second step, respectively compared to control (27.1%), but decreased to 52.5% after the third step. The single embryo transfer rate increased to 21.7%, 21.0% and 43.6% in three steps, respectively compared to control (13.4%). Implantation rate increased significantly from 19.4% (control) to 26.6% (after third step) (P⬍0.01).Pregnancy rate increased significantly from 33.5% to 43.6% after second step (P⬍0.01). The multiple pregnancy rates significantly decreased from 33.3% to 16.3% in second step (P⬍0.01). FTET; Implantation rate significantly increased from 13.3% to 18.7% in the first step(P⬍0.05), and from 23.0% to 35.6% in the third step(P⬍0.01), respectively. Pregnancy rate significantly increased to 33.7% to 44.2% in the third step. The multiple pregnancy rate decreased gradually from 32.6% to 22.1% (not significant) in the third step. CONCLUSION: The second step was effective to decrease the multiple pregnancy rate and increase the pregnancy rate in FET. The implantation rate has been going up in FTET owing to vitrification method. Our next stage will be done elected single embryo transfers in all patients of under the age of 40, especially in FTET. Supported by: None

P-303 IMPLANTATION, CLINICAL PREGNANCY AND MISCARRIAGE RATES ONE-YEAR AFTER THE INTRODUCTION OF ULTRASOUND-GUIDED EMBRYO TRANSFER: A COMPARATIVE STRATIFIED ANALYSIS. C. Rubina Ali, L. G. Nardo, G. Horne, C. Fitzgerald. St. Mary’s Hospital, Manchester, United Kingdom. OBJECTIVE: Embryo transfer is a crucial step in assisted reproductive technology. Clinical pregnancy rates are influenced by several factors and nearly 85% of all embryos transferred in the uterine cavity fail to implant. With an increasing trend toward elective single embryo transfer, techniques to improve embryo culture and embryo transfer become even more important in order to maintain the pregnancy rates. Aim of this retrospective comparative study was to compare the pregnancy outcome between ultrasound-guided embryo transfers (USS-ETs) and non USS-ETs in a tertiary IVF unit. DESIGN: Retrospective comparative study. MATERIALS AND METHODS: In the year Nov 2003 to Oct 2004, which preceded the introduction of USS-ET, 891 consecutive fresh and frozen embryo transfers were carried out. A long gonadotrophin releasing hormone agonist desensitization protocol was used for controlled ovarian stimulation in all patients undergoing a fresh treatment cycle. Following oocyte retrieval, fertilization was achieved by either conventional IVF or ICSI. Strict criteria for embryonic development staging and grading were adopted. All women underwent uterine sounding prior to replacement and embryo transfers were carried out using the thin walled soft Embryon®

FERTILITY & STERILITY威

catheter. Frozen embryo transfer cycles were performed using down-regulation and sequential oestrogen/progesterone replacement therapy until an endometrial thickness ⱖ 7mm was obtained. Between Nov 2004 and October 2005, 842 consecutive fresh and frozen USS-ETs were performed. Apart from the introduction of ultrasound, no other changes were made. Implantation, clinical pregnancy and miscarriage rates were compared between USS-ET group and non USS-ET group. Statistical analysis was carried out using the Chi-square test and a P-value of ⬍ 0.05 was considered statistically significant. RESULTS: The patients in the two study groups were comparable for demographics and clinical characteristics. Three-hundred ninety-four fresh and 448 frozen USS-ETs were carried. In the year immediately preceding, 385 fresh and 496 frozen non USS-ETs were performed. The implantation rate was significantly higher in the USS-ET group compared to the non USS-ET group (fresh: 20% vs. 9.5%, P⫽0.0001; frozen: 13% vs. 7.0%, P⫽0.0004). Similarly, the clinical pregnancy rate was significantly higher in the former study group (fresh: 26.9% vs. 12.4%, P⫽0.001; frozen: 15.6% vs. 8.8%, P⫽0.001). The miscarriage rate was increased in the frozen embryo transfers performed under ultrasound guidance (8.9% vs. 5.6%, P⫽0.027), but no other statistically significant differences were found. There was no difference in the ectopic pregnancy rates between the two groups. CONCLUSION: Our findings show that the practice of USS-ET is associated with an increased likelihood of successful pregnancy outcome. Both implantation and clinical pregnancy rates were statistically higher when the embryo transfer was performed under ultrasound guidance. The increased miscarriage rate observed in the subgroup of patients undergoing frozen embryo transfer is likely to be the result of various other factors including embryo quality after freezing/thawing and embryo-endometrium cross-talk rather than the ultrasound-based approach of embryo transfer. These data add to the available evidence supporting the use of USS-ET in assisted reproductive technology. Supported by: None

P-304 USE OF EGG DONATION CASES TO EVALUATE A STANDARDIZED “FIXED DISTANCE” EMBRYO TRANSFER TECHNIQUE WITHOUT ULTRASOUND GUIDANCE. T. T. Huang, P. I. McNamee, C. N. Chan, A. Tunac, T. Kosasa, C. T. Huang. Univ. Hawaii School of Medicine, Honolulu, HI; Pacific IVF Institute, Honolulu, HI; Advanced Reproductive Center of Hawaii, Honolulu, HI. OBJECTIVE: The necessity for ultrasound guidance during the embryo transfer remains controversial. Egg donation cases represent a uniform good prognosis group that can minimize potential confounding variables of egg and embryo quality. The purpose of this study was to evaluate outcomes in such cases using a standardized, “Fixed Distance” embryo transfer (ET) protocol without ultrasound guidance. DESIGN: Retrospective descriptive study in a private practice setting. MATERIALS AND METHODS: The study group consisted of 67 sequential egg donation cases having a fresh embryo transfer during a threeyear period (2003-2005). Conventional insemination was performed in 40/67 (59.7%) patients, with ICSI utilized in 27/67 (40.3%) cases. All recipients had hormone replacement using leuprolide acetate, Estrogen, and Progesterone. Prior to the treatment cycle, a “mock transfer” was performed on each patient using detailed uterine sounding and/or sonographic measurement to obtain a precise endometrial cavity length. Based on embryo quality assessment on Day 2, patients were allocated to either Day 3 (n⫽26) or blastocyst transfer on Day 5 (n⫽ 41), with the number of embryos transferred based on SART guidelines. This typically involved up to 2-3 top quality embryos for D3 and 2 top quality blastocysts for D5 ET’s. A trial transfer was performed just prior to the fresh ET to confirm catheter choice as “soft” (Wallace, Sage) or “rigid” (Tefcat). Vigorous endocervical lavage was performed to remove cervical mucus using 10-15cc of culture medium using a syringe attached to a Wallace catheter outer sheath. Embryos were released 0.5-1.0 cm from the endometrial cavity length determined during the pretreatment “mock transfer”. The catheter was gradually removed 20 seconds after embryo release. Total pregnancies were measured as doubling of HCG values (⫹ HCG) at 12 and 14 days after EPU, with subsequent clinical pregnancies determined by ultrasound confirmation at 7 weeks (⫹Clin). Gestational sacs were used to determine implantation rates (IR). RESULTS: Total pregnancies (⫹HCG) were observed in 49/67 (73.1%)

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