Comparison between international standard organization (ISO) type 5 and type 6 cleanrooms combined with volatile organic compounds filtration system for micromanipulation and embryo culture in severe male factor infertity.

[P-593] COMPARISON BETWEEN INTERNATIONAL STANDARD ORGANIZATION (ISO) TYPE 5 AND TYPE 6 CLEANROOMS COMBINED WITH VOLATILE ORGANIC COMPOUNDS FILTRATION SYSTEM FOR MICROMANIPULATION AND EMBRYO CULTURE IN SEVERE MALE FACTOR INFERTILITY.

S. C. Esteves, S. Verza Junior, A. P. Gomes. ANDROFERT – Centro de Referência em Infertilidade Masculina, Campinas, Brazil

Objective: It has been shown that airborne concentrations of toxics volatile organic compounds (VOC), chemical contaminants and particles may impair embryo development and pregnancy rates. Filtration units can clean the air of the in vitro fertilization (IVF) laboratory and decrease contamination with different efficiency levels. Cleanrooms are contaminated-free environments useful for certain critical applications in bioengineering, pharmaceutical and computer industries. The aim of this study was to evaluate the impact of high standard measures for air quality control inside the IVF laboratory and adjacent areas on fertilization, cleavage, embryo development, pregnancy and miscarriage rates in ICSI cycles for severe male factor infertility.

Design: Retrospective cohort study.

Material and methods: This study included 399 consecutive ICSI cycles to treat severe male infertility from April 2000 to December 2003. Cycles were divided in two groups according to the air filtration system efficiency in the IVF lab: group 1 (ISO 6 IVF laboratory; n=187) and group 2 (ISO 5 IVF lab; n=212). ISO 6 laboratory was equipped with a positive pressure high efficiency particles air filtration (HEPA) system and a free-standing unit to filter and remove VOC. ISO 5 laboratory was built with proper engineering and material selection, and with a dedicated air handling system equipped with HEPA and carbon-impregnated filters located in a separate room to filter and remove particles and VOC from the ART laboratory and adjacent areas such as oocyte retrieval and embryo transfer rooms. A positive pressure differential was maintained from the 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.

Comparison of laboratory parameters in two different Cleanrooms for ICSI in male infertility
ISO 6 IVF lab n=187 ISO 5 IVF lab n=212 p value
Sperm source: ejaculated; epidydimal and testis (%) 84.0; 6.0; 10.0 88.0; 4.0; 8.0 NS
Fertilization rate 2PN (%) 70.0 ± 25.4 69.7 ± 22.4 NS
Cleavage rate (%) 84.8 ± 28.2 94.1 ± 15.9 <0.001
Good quality embryo on day 3 (%) 34.3 ± 28.7 49.4 ± 31.5 <0.001
Embryo transfer (n) 3.5 ± 1.8 3.4 ± 1.3 NS
Clinical pregnancy rate (%) 36.9 47.1 0.03
Miscarriage (%) 25.0 14.0 0.01
NS = not significant

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.