Evaluation of minimal stimulation IVF with clomiphene citrate and hMG

for 338 recipients, performed in our Center in October 2005-February 2007. Our program is based on sharing the donated oocyte cohort among several matched recipients, allocating a minimum of 4 MII oocytes to each recipient. The COH is performed with highly purified human menopausal gonadotropins (HP-hMG) 300 IU/day, using either GnRH agonist (luteal phase step-down protocol) or antagonist protocols as convenient for donorrecipient coordination. Recipients have the endometrium replaced with 17beta-estradiol with or without GnRH agonist use depending on the ovarian activity. Progesterone intravaginally was started after documenting fertilization. Embryo transfers were performed on day 2 or day 3 post-aspiration. Recipients were retrospectively divided between those who received oocytes from donors that provided <20 MII oocytes and those that donated R20.We further divided the donors in six groups (A:<8 MII oocytes; B:8–11; C:12–15; D:16–19; E:20–23; F:>23 MII oocytes) according to the number of oocytes retrieved for their matched donors. In order to reduce potential confounding variables, a subgroup analysis was performed restricting the cohort of recipients to those that have received <7 MII oocytes. Statistical analysis was done by using chi square test. RESULTS: We did not find any statistical difference between both groups in fertilization rates (78.8% vs. 78.9%), implantation rates (29.2% vs. 28.4%), clinical pregnancy rates (47.0% vs. 46.1%) and miscarriage rates (8.0% vs. 7.8%). Also, there were no differences among the six sub-groups analyzed neither in pregnancy rate (A ¼ 38.1%; B ¼ 46.3%; C ¼ 54.4%; D ¼ 44.2%; E ¼ 42.1%; F ¼ 47.8%) nor in all the other clinical parameters listed above. CONCLUSIONS: High ovarian response among oocyte donors does not seem to impact on oocyte donation outcomes. The lower pregnancy rates in ART patients with high ovarian response found by some authors (Testar 1986; Ludwig 1999) may be by impacting negatively on the receptive endometrium but not on the quality of oocytes or embryos. Supported by: None. P-540 THE EFFECTS OF GnRH ANTAGONIST VS. GnRH AGONIST DOWN REGULATION ON THE OUTCOME OF IUI CYCLES. K. Sakhel, M. Abuzeid. Synergy Medical Education Alliance, Michigan State University, Saginaw, MI; IVF Michigan PC, Rochester Hills, MI; Division of Reproductive Endocrinology, Hurley Medical Center, Michigan State University, Flint, MI. OBJECTIVE: It has been shown that up to 24% of non-down-regulated COH/IUI cycles may suffer premature luteinization. The use of down-regulation in controlled ovarian hyperstimulation (COH)/IUI cycles has improved pregnancy rates as compared to non-down-regulated cycles. The aim of this study is to compare the efficacy of GnRH antagonist to GnRH agonist down-regulation in COH/IUI cycles. DESIGN: Historical cohort study. MATERIALS AND METHODS: The cycle information on all patients who underwent IUI during the period of April 1990-February 2004 at our referral center was being collected prospectively. The patients had similar ovarian stimulation protocols, with pure FSH and/or HMG and either midluteal GnRH agonist protocol (Group 1) or GnRH antagonist (Group 2). A total of 1884 consecutive cycles were included. All patients had a single IUI performed 42 hours after HCG injection. Ovulation was documented by a vaginal ultrasound scan prior to the IUI. Statistical analysis was performed using the Student’s t-test and c2 where appropriate. Multiple logistic regression analysis was performed to control for age, type and duration of infertility and the number of follicles R16 mm.

compared to 1210  810 pg/ml)were significantly greater in the GnRH agonist group compared to the GnRH antagonist group (P¼0.001 and P¼0.01 respectively). After multiple logistic regression analyses, the type of infertility and the number of 16 mm follicles remained significant factors. The pregnancy rates in the 2 groups were similar (31.9% and 28.1% for group 1 and group 2 respectively). The delivery, miscarriage and ectopic pregnancy rates were similar in the 2 groups (Table 1). CONCLUSIONS: Both GnRH Antagonist and GnRH agonist appear to have similar effectiveness during COH/IUI cycles. Supported by: None. P-541 EVALUATION OF MINIMAL STIMULATION IVF WITH CLOMIPHENE CITRATE AND hMG. T. Segawa, K. Kato, O. Miyauchi, S. Kawachiya, Y. Takehara, O. Kato. Kato Ladies Clinic, Shinjuku-ku, Tokyo, Japan. OBJECTIVE: Minimal stimulation protocol IVF with clomiphene citrate (CC) has been offered to patients at our clinic in an effort to reduce the cost of medication and occurrence of OHSS. In this study, we evaluated whether combination of hMG was necessary for the minimal stimulation IVF protocol with CC. DESIGN: Retrospective study. MATERIALS AND METHODS: This was a retrospective study that included CC cycles (n ¼ 3654) in Japanese infertile women received IVF treatment at our clinic between October 2005 and July 2006. All cycles were divided three groups; group A (n ¼ 941): CC þ hMG(150IU), group B (n ¼ 1267): CC þ hMG(75IU), group C (n ¼ 1446): CC only. Informed consent was obtained before this study for all patients. In all cycles, CC was given at a dose of 50mg/day from day 3 of cycle. In group A and B, hMG were given at a dose of 75 or 150 IU every other day starting on day 8 of cycle. In patients of any groups, when the average diameter of dominant follicle was reached to 18 mm, 600 mg GnRHa (buserelin acetate) was administered to trigger endogenous LH surge. All oocytes were performed regular insemination or ICSI, and single embryo transfer (SET) were performed 2 days after oocyte retrieval. All surplus of embryos were vitrified at 4–8 cells or blastocyst stage. Pregnancy was assessed based on serum hCG levels at 12 days after embryo transfer. RESULTS: There were no difference among three groups in patient’s age, duration of infertility, and cause of infertility. Total amount of hMG (IU) was significantly higher in group A than in group B (412  152 vs. 167  72; P<0.001), but they were relatively low dose of hMG. Serum E2 level (pg/ml) at day of GnRHa administration was significantly lower in group C than in group A and B (662  303 vs. 1296  759 and 840  420; P<0.001). The number of available embryos was significantly lower in group C than in group A and B (0.9  1.0 vs. 2.1  2.0 and 1.4  1.3; P<0.001). The pregnancy rate per transfer also was lower in group C than in group A and B (24.3% vs. 34.1% and 34.2%; P¼0.002). In addition, the number of usable vitrified embryos was significantly higher in group A than in group B and C (1.1  1.5 vs. 0.5  0.9 and 0.3  0.7; P<0.001). CONCLUSIONS: We conducted that combination of hMG (150IU) in minimal stimulation protocol with CC can contribute to the good IVF outcome including next freeze-thawed embryo transfer cycle. We suggested that all IVF patients have to be treated by minimal stimulation protocol with CC and low amount of hMG to reduce occurrence of OHSS and multiple pregnancy. Supported by: None.

P-542 TABLE 1. Comparison of GnRH agonist cycles to GnRH antagonist cycles outcome

Pregnancy Delivery Miscarried Ectopic

GnRH agonist (n  1258)

GnRH antagonist (n  626)

Total (n ¼ 1884)

P

353 (28.1%) 276 (21.9%) 63 (17.8%) 14 (4.05)

199 (31.9%) 163 (26.0%) 26 (13.1%) 10 (5.0%)

552 (29.3%) 439 (23.3%) 89 (16.1%) 24 (4.3%)

NS NS NS NS

RESULTS: The mean age for all the women was 32  4.5 years. There was no significant difference in the mean age between the two groups. However, the mean duration of infertility was significantly longer (P¼0.01) and the proportion of primary infertility was significantly greater (P¼0.02) in the GnRH antagonist group. The mean number of follicles R16 mm (4.9  3.0 compared to 4.2  2.6) and the mean peak estradiol (E2) (1480  850 pg/ml

S286

Abstracts

CESSATION OF GNRH ANTAGONIST ADMINISTRATION ON hCG DAY COULD IMPROVE OUTCOMES OF CONTROLLED OVARIAN HYPERSTIMULATION WITH GnRH ANTAGONIST FLEXIBLE MULTIPLE-DOSE PROTOCOLS. H. J. Chang, J. R. Lee, B. C. Jee, J. Choe, C. S. Suh, S. H. Kim. Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam, Korea; Obstetrics and Gynecology, College of Medicine, Seoul National University, Seoul, Korea; Obstetrics and Gynecology, Hamchoon Women’s Clinics, Seoul, Korea. OBJECTIVE: Recent meta-analyses have shown significantly lower pregnancy rates, serum estradiol levels on hCG day, and number of oocytes retrieved in GnRH antagonist (GnRHant) cycles compared with GnRH agonist cycles. Thus possible extrapituitary actions of GnRHant have been thought to affect controlled ovarian hyperstimulation (COH) outcomes and to be one of the causes of lower pregnancy rates. Withdrawal of GnRHant could immediately reverse antagonizing effect, therefore cessation of GnRHant administration on hCG day could remove the possible detrimental

Vol. 88, Suppl 1, September 2007