Naslov
A prospective study evaluating the effect of high (21%) and low (5%) oxygen levels on the human embryo development

Autori
Gelo, Nina ; Stanić, Patrik ; Hlavati, Višnja ; Šogoric, S ; PAvičić Baldani, Dinka ; Šprem Goldštajn, Marina ; Radaković, Branko ; Kasum, Miro ; Strelec, Mihajlo ; Šimunić, Velimir ; Vrčić, Hrvoje

Izvornik
Human reproduction. Supplement (1359-5911) 26 (2013), 1; 322-322

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, kongresni sažetak, znanstveni

Ključne riječi
oxygen levels; human embryo development

Sažetak
The purpose of this study was to examine effect of low O2 (5%) levels in order to obtain more embryos with excellent morphology (grade Z1, A, AA) as well as higher clinical pregnancy rates (CPR). Cultivation of embryos in incubators with low oxygen (5%) levels contributes their better development on day 2, enhances the rate of blastocysts and those blastocysts results with higher number of CPR. Oxygen is the major factor in embryo development in vitro along with cultivation medium. Excess of reactive oxygen species (ROS) results with damage known as oxidative stress (OS) which can cause DNA fragmentation, apoptosis, slowing or even stopping of embryo development. Excess of ROS is more common in cultures with high (21%) oxygen levels. Between March 2012 and May 2012, 70 IVF and ICSI stimulated cycles were prospectively randomized for cultivation with high (21%) or low (5%) oxygen level. Until the time of fertilization all oocytes were cultivated with high (21%) oxygen level and after that cultivated according to the prior randomization. Embryo development was monitored every 24 hours (except on day 4) for 3 or 5 days according to the day of transfer. Statistical analysis was performed with StatSoft program and results were compared with chi-square test with Yates correction with df=1. A P value ≤0. 05 was considered statistically significant. Statistically significant difference was observed with embryos on day 2 – 52.2% (47/90) grade A embryos developed with 5% O2 and 37.4% (34/91) with 21% O2 , number of embryos that stopped in development – 5.6% (5/90) with low oxygen and 15.4% (14/91) with high oxygen levels and number of embryos that reached blastocyst stadium – 21.1% (19/90) with 5% O2 versus 6.6% (6/91) with 21% O2. Number of transfers on day 3 showed statistically significant difference for cultivation with high (21%) oxygen levels while number of transfers on day 5 showed statistically significant difference for cultivation with low (5%) oxygen levels – 88% versus 71.2% and 26% versus 8.9%.Number of CPR after transfer of blastocyst was statistically significant after cultivation in incubator with 5% O2 – 46.6% versus 10%.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti

POVEZANOST RADA