Results: The clinical pregnancy rate significantly increased in a linearfashion from 5 to 9 days of gonadotropin stimulation as determined bylinear regression analysis (P�0.001) at which time clinical pregnancy ratesplateaued. No pregnancies were observed with 16 or 17 days of gonado-tropin stimulation. These results suggest that clinical pregnancy rates im-prove with increased duration of gonadotropin stimulation, at least up to 9days.

In a second retrospective analysis, we compared pregnancy rates withadministration of hCG when the lead follicle diameter was 16 to 17 mm, 18to 19 mm, or greater than 20 mm. The results are presented in graphiccomparison and compared to an unmatched cohort of down-regulationpatients.

Conclusions: GnRH antagonists bind to gonadotrope GnRH receptors andcompete successfully with endogenous agonist GnRH molecules for recep-tor occupancy. Follicles are recruited earlier in antagonist cycles (NorthAmerican Ganrilex Study Group), but it now appears that there is a latedifference in follicular dynamics among stimulation protocols, as well. Theduration of gonadotropin stimulation associated with acceptable pregnancyrates is fairly broad (9 to 15 days). As the size of the lead follicle increasesin GnRH antagonist cycles, a concomitant increase in pregnancy ratesoccurs. Conversely, patients in agonist down-regulation treatment regimensdo not benefit from obtaining larger follicle sizes. Furthermore, it appearsthat increasing lead follicle size is a more accurate correlator of increasingpregnancy rates than increasing duration of gonadotropin stimulation.

Wednesday, October 15, 20032:45 P.M.

O-254

Serum anti mullerian hormone as a novel predictive factor of success inart among women with polycystic ovary syndrome? Andre Hazout,Anne Marie Junca, Alain Le Meur, Flavien Ternaux, Paul Cohen-Barcie.ART Unit Eylau Muette, Paris, France.

Objective: To compare the serum antimullerian hormone (AMH) levels inwomen with polycystic ovary syndrome (PCOS) and those in womenwithout PCOS, and to define AMH as a predictive factor of success in ART.

Design: Retrospective study concerning 413 patients undergoing ARTprocedure (IVF or ICSI).

Materials and Methods: Two hundred thirty-two sonographically and

hormonally diagnosed women with PCOS (LH mean value � 6 �1.8IU/mL and FSH mean value � 7�1.2 IU/mL) were compared to a controlgroup of 181 women without PCOS. On cycle day 3, serum levels of AMH,FSH, estradiol (E2), inhibin B (INHB), and LH were measured within thetwo months before the procedure of ART. We compared between the twopatients groups the age, serum levels of each hormone, number of retrievedoocytes, number of embryos obtained at day two and the rate of ongoingpregnancy .Statistical analysis was computed for each parameter in allpatients groups.

Results: Among the 232 women with PCOS, the AMH serum levels in 79pregnant patients (mean age: 34.9�1.2 yrs) and in 153 non pregnantpatients (mean age: 35.16�1.3 yrs) were respectively 3.09�1.2 and1.96�0.8 ng/mL (P- value �0.00005), INHB serum levels were 75.2�12.2and 74.18�14.2 pg/mL (P- value � 0.01), E2 serum levels were 24.1�14and 25.9�15 pg/mL and the FSH serum levels were 6.28�1.1 and 6.58�1.15 IU/mL (P- value �0.05). The mean age and E2 serum levels werenot statistically different between the pregnant and non pregnant women.The number of retrieved oocytes (7,9�4.2) and embryos (5,8�3.1) washigher in the pregnant group compared to the non pregnant group (respec-tively 6.5�3.5 and 5�2.8). Among the control patients group (58 pregnantand 123 non pregnant patients) the AMH serum levels respectively2.15�1.7 and 0.97�1.3 ng/mL (P- value � 0.005) were less correlated tothe number of retrieved oocytes or embryos or to the number of ongoingpregnancies than in the studied group.

Conclusion: AMH serum levels at day 3 seems to be a good predictivefactor to the outcome of ART in women with PCOS.

Wednesday, October 15, 20033:00 P.M.

O-255

Ejaculatory abstinence less than 3 days results in a higher pregnancyrate (PR) following intrauterine insemination (IUI). Marcus W. Jurema,Andrea D. Damasceno Vieira, Brandon Bankowski, Yulian Zhao, EdwardWallach, Howard Zacur. The Johns Hopkins Medical Institutions, Balti-more, MD; Univ de Brasilia (UdB), Brasilia, Brazil.

Objective: The duration of ejaculatory abstinence is known to affectsperm concentration and motility, while morphology remains relativelyconstant. The effect of the abstinence interval on pregnancy outcome is notwell characterized since most studies do not consider abstinence as anindependent variable. In this study, we examined the influence of theabstinence interval on sperm parameters and pregnancy rates following IUI.

Design: Retrospective analysis.Materials and Methods: 410 couples underwent 929 fresh, non-donor IUI

cycles performed between June 1999 and October 2002. The influence ofthe duration of abstinence on the processed sperm parameters (concentra-tion, motility, and total motile sperm [TMS]) and PR was analyzed byPearson’s correlation. The impact of each of these parameters, includingduration of abstinence, on PR was evaluated by stepwise logistic regression.ANOVA and independent t-tests were used to compare means.

Results: Duration of abstinence correlated positively with sperm concen-tration and TMS, but negatively with motility. PR correlated negatively withduration of abstinence (r � �0.083, p � 0.05). Logistic regression revealedthat only the duration of abstinence had a significant impact on PR. Table1 shows the PR according to the abstinence interval. There were nodifferences in male or female age within or between the groups. Anabstinence interval of � 3 days had the highest mean PR (14%), while aninterval of 4 to 10 days had a lower mean PR (10%), and an abstinenceinterval � 10 days had the lowest mean PR (3%) [Figure 1]. Theseabstinence interval groups were statistically different from each other (p �0.05).

* p � 0.05 compared to � 10 days.

FERTILITY & STERILITY� S97

Figure 1. Mean pregnancy rates of abstinence interval groups in IUIcycles.

Conclusions: In the literature, the optimal duration of abstinence beforeperforming a semen analysis or artificial insemination varies from 2 to 10days. In clinical practice a 3 to 5 day interval is most commonly recom-mended. This study provides evidence that an abstinence interval �3 daysimproves the pregnancy rates following IUI, and that abstinence should bemonitored as an independent factor in future studies evaluating spermparameters and reproductive outcome. The correlation between duration ofabstinence and pregnancy rate was not explained by sperm concentration,motility, or TMS and may be due to factors not accounted for by routinesemen analysis.

Wednesday, October 15, 20034:00 P.M.

O-256

Offspring gender ratios differ between day 3 and day 5 embryo trans-fer. Carolyn McCaffrey, Alan Berkeley, Jamie Grifo, Lisa Kump, Freder-ick Licciardi, Nicole Noyes. New York Univ Sch of Medicine, New York,NY.

Objective: An association between the rate of embryo development invitro and gender has been suggested by observations in domestic animalsthat male embryos develop faster than female siblings. In our IVF program,embryos selected for transfer on Day 3 are chosen on the basis of quality;blastomere number routinely ranges between 5 and 9 cells and embryos withlarger cell numbers are rarely transferred. However, on Day 5 embryoselection is primarily based on developmental stage and the most advancedstage blastocysts are preferentially transferred. This study assesses whetherthese different embryo selection strategies impact on the gender ratioobserved at birth.

Design: Retrospective analysis of live birth outcomes of IVF and donoroocyte (OD) cycles conducted at a large university-based IVF program in2000-2001.

Materials and Methods: At cycle onset, all IVF patients and OD recipi-ents are eligible for a Day 5 embryo transfer (ET); however, depending onoocyte number, fertilization rate and subsequent embryonic development,the transfer may be converted to Day 3. As a general policy, patients with3 or more 6-8 cell embryos (grade 2.5 or better) on Day 3 continue to a Day5 ET, otherwise their best quality embryos are hatched and transferred thatday. On Day 5, the most advanced blastocysts are selected for ET sinceimplantation and pregnancy rates are highest when advanced stage blasto-cysts (Stage 3-5) are transferred. This analysis includes all Day 3 and Day5 ETs which resulted in the live birth of an offspring of known gender. Datawere analyzed by X2 test.

Results: Day 3 ETs resulted in gender ratios of 243:234 and 43:34 for IVFpatients and OD recipients. In contrast, the respective ratios for Day 5 ETs,

278:203 and 113:70, reflected significantly greater tendencies for maleoffspring. Similar ratios were noted when Day 5 ET cycles were separatelyanalyzed as ICSI and non-ICSI cycles. Stage 3-5 blastocysts were trans-ferred in 70% of the Day 5 ETs, but statistically significant relationshipsdid not exist between blastocyst stage and gender.

Conclusion: Our data indicates that, for Day 5 ET, selecting embryosaccording to developmental status only skews the sex ratio of the offspringto favor males. The observation that this pattern persists in ICSI andnon-ICSI cases suggests that in humans, the rate of development throughearly embryogenesis varies between male and female embryos.

Wednesday, October 15, 20034:15 P.M.

O-257

Post-processed semen specimens with deficits in strict morphology maynot require intracytoplasmic sperm injection (ICSI) to achieve goodreproductive outcomes. Natan Bar-Chama, Jason Barritt, Marlena Duke,Kathleen Miller, Richard Scott, Alan Copperman. Reproductive MedicineAssoc of New York, New York, NY; Reproductive Medicine Assoc of NewJersey, New Jersey, NJ.

Objective: To determine if performing ICSI improves clinical outcomesin assisted reproductive technology (ART) cases when a Kruger strictmorphology of only 3 and 4 % normal sperm is present.

Design: 4,603 ART cycles performed from August 1, 1999 to April 1,2003 underwent a retrospective data analysis.

Materials and Methods: Sperm strict morphology was determined usingKruger strict criteria and performed on the post processed semen sampleused for the ART cycles. Fresh semen samples for IVF were placed on athree layer gradient and washed twice prior to morphological assessment.Oocytes of patients with Kruger morphology of �2% were triaged to ICSI.Patients with Kruger morphology of �5% were triaged to conventionalinsemination. Patients with Kruger morphology of 3 or 4% were treatedbased on patient history and at the embryologist’s discretion. 2,490 ARTcycles of conventional IVF with a Kruger of �5% normal forms (group1),1,646 cycles of ICSI with a Kruger of �5% normal forms (group 2), 111cycles of conventional IVF with a Kruger of 3 and 4% normal forms (group3) and 356 cycles of ICSI with a Kruger of 3 and 4 % normal forms (group4) were reviewed. Fertilization rate, % of embryos with �7 cells on daythree, and clinical pregnancy rates (defined as the presence of a gestationalsac on ultrasound examination) was compared across all four groups.Statistical analysis was performed using Chi-square analysis.

Results: Fertilization rates of 59.2% (21,390/36,116), 58.6% (14,699/25,079), 61.2% (883/1,442) and 68.8% (3,217/4,676) were noted for groups1,2,3, and 4 respectively. High quality day 3 embryos were created in 55.2%(11810/21390), 51.3% (7540/14699), 56.4% (498/883) and 54.1% (1740/3217) for groups 1,2,3, and 4 respectively. Clinical pregnancy rates of59.8% (1489/2490), 59.2% (973/1,646), 55.1% (63/111) and 61.7% (221/356) were achieved for groups 1,2,3, and 4 respectively. Fertilization ratewas significantly improved by ICSI vs. conventional IVF when the Krugerscore was 3 and 4% (p � 0.001). Fertilization rate was significantly higherfor conventional IVF vs. ICSI when the Kruger score was �5 (p � 0.001).High quality day 3 embryo production was significantly improved usingconventional IVF vs. ICSI when the Kruger score was �5 (p � 0.001). Highquality day 3 embryo production was not significantly decreased using ICSIvs. conventional IVF when the Kruger score was 3 and 4%. Clinicalpregnancy rates were not significantly different for ICSI vs. conventionalIVF when the Kruger score was �5%. Clinical pregnancy rates were notsignificantly different for conventional IVF with a Kruger of 3 and 4%(group 3) vs. ICSI with a Kruger of 3 and 4% (group 4), conventional IVFwith a Kruger of �5% (group 1) or ICSI with a Kruger of �5% (group 2)(p � 0.05).

Conclusion: Clinical parameters to determine when ICSI is preferred arecomplex and continue to evolve. Not all ART cycles require ICSI to attainadequate pregnancy rates when in the absence of other mitigating factors,

S98 Abstracts Vol. 80, Suppl. 3, September 2003