RESUMO
Background: Amongst various other factors, oxygen (O2) concentration in embryo culture plays an important role in determining pregnancy outcomes in women undergoing in vitro fertilisation. Some studies have reported that lowering O2 levels in embryo culture provides better results. Aims: To explore the effects of low- and ultra-low- O2 concentrations (5% and 2%, respectively) in extended embryo culture on various outcome parameters of pregnancy. Settings and Design: This was a retrospective cross-sectional study. Materials and Methods: In this study 382 participants had their embryos cultured in varying O2 concentrations (5% or 2%), followed by either a fresh embryo transfer (ET) or frozen embryo transfer (FET). Outcomes such as pregnancy rate, implantation rate, abortion rate, twinning rate, and live birth rate were compared between the groups. Statistical Analysis Used: Chi square test was applied to compare the primary and secondary outcomes between different groups. Results: No significant differences were observed in pregnancy rate and implantation rate between 5% and 2% O2 groups, irrespective of their mode of ET. The abortion rate was significantly higher in 5% O2 group than in 2% group during FET (24.71% vs. 11.49%, P = 0.02). While the proportion of good-quality embryos was higher in 5% O2 group, these did not translate to better pregnancy outcomes. Additionally, embryos cultured in 2% O2 concentration had a significantly better implantation rate when they were transferred fresh rather than frozen (71.34% vs. 61.46%, P = 0.04). There were no other differences observed. Conclusion: Only marginal benefits were observed in switching human embryos to ultra-low O2 concentration after the initial days of culture.
RESUMO
Background: It is well established that high-quality semen can lead to an improved fertilisation rate. Ejaculatory abstinence (EA) certainly can influence sperm quality such as volume, count, motility and morphology. However, very few studies have addressed the influence of EA on intracytoplasmic sperm injection (ICSI) outcome and especially in males with severe oligo-asthenoteratozoospermia (OAT) syndrome. Aim: This study was undertaken with the purpose of evaluating the advantage of shorter abstinence period (1-h sequential ejaculation) in males with severe OAT syndrome on total usable embryo rate and thereby emphasising the potential application of consecutive ejaculate. Study Setting and Design: This retrospective cohort study consisted of all the infertile couples undergoing ICSI cycle with the indicated seminal characteristics who had consulted the tertiary care hospital between January 2021 and July 2021. Materials & Methods: All couples in the study had idiopathic male infertility. Retrospectively, two groups were analysed, i.e., Group A with 56 subjects in which first semen sample was used for ICSI cycle and another Group B with 41 subjects in which second semen sample collected within a shorter abstinence period of 1 h was used. Statistical Analysis: The data were descriptively analysed using GraphPad Prism (vs. 9.2). Unpaired t-test and analysis of variance test were used to determine the significance. P < 0.05 was considered statistically significant. Results: The age of female subjects in Group A was 29.9 ± 3.5 years while it was 29.4 ± 3.4 years in Group B. Similarly, the age of male subjects was 32.2 ± 3.6 years and 31.9 ± 4.1 years in Group A and Group B, respectively, with no statistical differences in any gender between the groups (P > 0.05). Apart from initial progressive motility (P = 0.004), none of the parameters such as total volume, total sperm count and morphology were significantly different (P > 0.05) between Group A and samples of Group B. Similarly, parameters such as volume (P = 0.006) and post-wash motility (P < 0.001) were significantly different between Group A and samples of Group B. However, there was no significant difference in sperm count and morphology (P > 0.05). Grade 1 embryos on day 3 were 345 (62.8%) in Group A and 170 (54.3%) in Group B. Overall, the total usable embryos in Group A and Group B were 222 (40.4%) and 148 (47.3%), respectively (P > 0.05). Conclusion: With regard to compromised sperm parameters, our findings do suggest that the second ejaculate is quite relevant to 'in vitro' reproductive treatments and a simple request for a second consecutive ejaculate (shorter abstinence period of 1 h) could provide the same results in terms of fertilisation. We observed the increased chances of usable embryos in the second ejaculate group.