P-594

ISO 5 IVF laboratory to the oocyte retrieval (ISO 6 Cleanroom) and the embryo transfer rooms (ISO 7 Cleanroom). Ovarian stimulation, gametes handling techniques and micromanipulation, embryo culture and transfer protocols were identical in both groups. Main outcome measures were normal fertilization and cleavage rates, percentage of good quality embryos available for transfer on day 3, clinical pregnancy and miscarriage rates. Data were analyzed by Mann Whitney U test or Chi2, as appropriate. RESULTS: Female age, number of oocytes retrieved per cycle and proportion of ICSI cycles involving microinjection of epidydimal or testicular spermatozoa were not statistically different between groups. Main results are show in the table. Values are expressed as mean⫾SD.

cryopreservation was obtained. In all of them, HYPO or MA were seen on testis histology. CONCLUSION: Testicular histology is predictable of the chance of finding spermatozoa by micro-TESE in men with nonobstructive azoospermia. Hypospermatogenesis and SCO had the best and worst prognosis either for SSR and for cryopreservation of exceeding spermatozoa, respectively. Adequate pregnancy rates are achieved by ICSI in such cases, but miscarriage is frequent. Supported by: None

P-595 MODIFIED PROCESSING OF TERATOZOOSPERMIC SPECIMENS WITH A HIGH INCIDENCE OF PINHEAD FORMS FOR ICSI. J. R. Correa-Pe´rez, R. Ferna´ndez-Pelegrina, K. Kaskar, P. M. Zavos. Infertility & IVF Center, Town & Country, MO; Centro de Fertilidad del Caribe, Rı´o Piedras, PR; Andrology Institute of America,, Lexington, KY; Andrology Institute of America, Lexington, KY.

CONCLUSION: Sperm quality may be a determinant factor for embryo development in ICSI cycles in severe male infertility. The control of air pollution in the IVF laboratory and critical adjacent areas may impact on embryo development in such cases, and may increase clinical pregnancy and decrease miscarriage rates. Our observations are consistent with an association between the presence of air contaminants in the IVF laboratory and impairment of embryonic development. Supported by: None P-594 SUCCESSFUL RETRIEVAL OF TESTICULAR SPERMATOZOA BY MICRODISSECTION (MICRO-TESE) IN NONOBSTRUCTIVE AZOOSPERMIA IS RELATED TO TESTICULAR HISTOLOGY. S. C. Esteves, S. Verza Jr., A. Prado Gomes. ANDROFERT-Centro de Refereˆncia em Infertilidade Masculina, Campinas, Brazil. OBJECTIVE: Several studies report higher sperm retrieval rate (SRR) by microdissection testicular sperm extraction (Micro-TESE) than by conventional TESE in nonobstructive azoospermic men. The objective of this study was to analyze SRR by micro-TESE in relation to testicular histology. DESIGN: Retrospective clinical study. MATERIALS AND METHODS: Fourty-two men with nonobstructive azoospermia underwent micro-TESE from October/02 to May/05. Of them, one had a AZFc microdeletion and one a nonmosaic Klinefelter syndrome. Testicular parenchyma (single piece measuring ⬃3X3X3mm) for histological evaluation was obtained prior or during micro-TESE. Testicular biopsies were classified based on the predominant histologic pattern as follows: (a) Sertoli-cell only (SCO), (b) Maturation arrest (MA) and (c) Hypospermatogenesis (HYPO). The mean age and serum FSH values in this series were 35.8 years and 27.3, 25.0 e 21.5 mIU/mL in each group, respectively. Fourteen patients underwent ICSI using testicular spermatozoa or elongated spermatids. RESULTS: Overall, testicular spermatozoa was found in 52.4% (22/42) micro-TESE cases. Hypospermatogenesis, MA and SCO were identified on histology in 7, 5 and 30 patients, respectively. The SRR in relation to testicular histology was 100% (7/7) for HYPO, 75% (3/4) for MA and 32.2% (10/31) for SCO. In another 10 SCO patients, only elongated spermatids have been found (32.2%). Sixteen ICSI cycles were performed, 11 using testicular spermatozoa and 5 with elongated spermatids. Fertilization, cleavage and good quality embryo rates using spermatozoa and spermatids were 54.4% and 42.3%, 97.1% and 93.3%, 52.8% and 27.7%, respectively. Pregnancy and miscarriage rates for ICSI cycles involving testicular spermatozoa were 72.7% (8/11) and 50% (4/8). No pregnancies were obtained in ICSI cycles using elongated spermatids. In 11 out of 22 (50.0%) successful sperm retrieval by micro-TESE, exceeding and adequate material for

S354

Abstracts

OBJECTIVE: Although it is argued that sperm morphology does not influence the fertilization outcome in ICSI, embryo development and implantation may be compromised. Processing methods are available to isolate selected sperm populations based on motility and morpholy. However, in cases of severe teratozoospermia, modifications are required to isolate morphologically normal sperm for ICSI. In this report, we describe a modified processing method to obtain sperm for ICSI in a subject with consistently ⬍1% normal morphology characterized by a high incidence of pinhead spermatozoa. DESIGN: Prospective clinical study. MATERIALS AND METHODS: A series of semen analyses on a subject revealed a high incidence (⬎ 78% total count) of pinhead spermatozoa. In order to identify possible modifications that will maximize the recovery of sperm without pinhead defects, the semen sample was divided into two aliquots and processed using either (1) double layer mini-density gradient centrifugation (DGC) with centrifugation at 100-300 g for 10min, and (2) swim-up for 60min (SU). The recovered sperm populations from these two methods (DGC-Proc and SU-Proc), as well as the left over raw samples (DGC-Raw and SU-Raw) were individually washed twice at 100 g for 2.5 min and assessed. On the day of oocyte retrieval, a semen specimen was collected and processed according to the methods tested. A total of 12 MII oocytes were retrieved of which 6 were injected via ICSI with sperm from the DGC-Proc sample and the remaining 6 oocyte were injected with sperm from the SU-Raw sample. RESULTS: The characteristics of the semen specimens processed via mini-DGC and SU are described in the table below. The semen specimen (Control-Raw) was totally teratozoospermic with 98% of abnormalities corresponding to pinhead spermatozoa and the remaining 2% corresponded to other head abnormalities. Pinhead spermatozoa showed the highest forward progression in comparison to the rest of the sperm population. Morphological abnormalities other than pinhead sperm consisted of variations in the size of the sperm head. Three embryos derived from the SU-Raw specimens were transferred on day 3 and resulting in an ongoing pregnancy.

CONCLUSION: Both the DGC-Proc and SU-Raw methods reduced the number of pinheads after preparation. In the swim-up method, the pinhead spermatozoa were able to reach the upper layer first due to their forward progression, leaving a lesser proportion of sperm without pinhead defects in the bottom layer, which is usually discarded in conventional swim-up. Furthermore, the SU-Raw sample showed a higher fertilization rate and better embryo quality when compared to the DGC method. Although sperm with normal morphology were not available, selection of sperm for ICSI was relatively simple since the ratio of sperm without pinhead defects increased in those specimens. This report demonstrates a novel approach for

Vol. 86, Suppl 2, September 2006