Can the endometrioma be an obstacle to complete oocyte retrieval in IVF cycles? A retrospective study.

OBJECTIVE: The study aimed to evaluate the utility and safety of ancillary maneuvers during oocyte retrieval for patients with endometrioma that makes ovum pick-up hard due to poor ovarian surgical accessibility. PATIENTS AND METHODS: Cases of 251 women with ovarian endometriomas undergoing in vitro fertilization (IVF) in our infertility unit were retrospectively analyzed to evaluate the clinical IVF cycle outcomes after oocyte retrieval. Controls (n = 251) were age-matched women without endometriomas who underwent an uncomplicated oocyte retrieval. RESULTS: No statistically significant differences were observed between groups except for the number of oocytes retrieved, which was higher in the control group than in the group of women with endometrioma. On the contrary, there were no differences between the experimental groups in the fertilization rate and number of embryos, and neither were there in the pregnancy and live birth rate. Moreover, the surgical complications were infrequent and similar between the two analyzed groups. Accidental or voluntary endometrioma punctures were not accompanied by increases in the risk of a pelvic infection. CONCLUSIONS: In conclusion, patients with endometrioma can undergo high-performance oocyte recovery procedures thanks to safe accessory maneuvers during the ovum pick-up.

Embryo culture at a reduced oxygen concentration of 5%: a mini review.

The optimum oxygen tension for culturing mammalian embryos has been widely debated by the scientific community. While several laboratories have moved to using 5% as the value for oxygen tension, the majority of modern in vitro fertilization (IVF) laboratory programmes still use 20%. Several in vivo studies have shown the oxygen tension measured in the oviduct of mammals fluctuates between 2% and 8% and in cows and primates this values drops to <2% in the uterine milieu. In human IVF, a non-physiological level of 20% oxygen has been used in the past. However, several studies have shown that atmospheric oxygen introduces adverse effects to embryo development, not limited to numerous molecular and cellular physiology events. In addition, low oxygen tension plays a critical role in reducing the high level of detrimental reactive oxygen species within cells, influences embryonic gene expression, helps with embryo metabolism of glucose, and enhances embryo development to the blastocyst stage. Collectively, this improves embryo implantation potential. However, clinical studies have yielded contradictory results. In almost all reports, some level of improvement has been identified in embryo development or implantation, without any observed drawbacks. This review article will examine the recent literature and discusses ongoing efforts to understand the benefits that low oxygen tension can bring to mammal embryo development in vitro.

Comparison of the development of human embryos cultured in either an EmbryoScope or benchtop incubator.

PURPOSE: In this current study, our main goal was to establish that EmbryoScope incubation environment is comparable to standard incubation. METHODS: The development of sibling human zygotes was compared after culture in either a benchtop incubator (SI) or an EmbryoScope time-lapse incubator (ES). Between May 2015 to April 2016, a total of 581 normally fertilized 2PN, pronuclear-stage embryos, from 47 patients were allocated to culture in either a benchtop incubator (SI) or an EmbryoScope incubator (ES). RESULTS: The development of embryos to cleavage (up to day 3) and blastocyst stages (day 5/6) was compared between the two different incubators. The proportion of good quality embryos was higher in the ES group compared to the SI on day 2 (66.8 vs. 50.5%, P = 0.014) and on day 3 (75.1 vs. 56.0%, P = 0.006). Those differences were statistically significant. A higher proportion of embryos developed to good quality blastocysts when cultured in the EmbryoScope compared to the benchtop (49.4 vs. 42.0%, P = 0.24), but this was not significant. Finally, no significant differences were noted with the proportion of blastocysts chosen for cryopreservation on day 5/6 in the two incubators. CONCLUSIONS: The findings support the view that the EmbryoScope incubator supports at least equivalent in vitro development of human embryos compared to other standard incubation methods and may promote improved development during early cleavage stages.

Cumulus gene expression as a predictor of human oocyte fertilisation, embryo development and competence to establish a pregnancy.

The close relationship between cumulus cell function and oocyte developmental competence indicates that analysis of cumulus gene expression is a potential non-invasive method to aid embryo selection and IVF outcome. Cumulus was isolated from 674 oocytes from 75 women undergoing ICSI and gene expression analysed by quantitative RT-PCR. Cumulus expression of cyclooxygenase 2 (PTGS2) was higher with mature oocytes, whereas brain-derived neurotrophic factor (BDNF) was lower when fertilisation was normal. Expression levels of gremlin (GREM1) and BDNF were weak positive and negative predictors of embryo quality respectively. Ranking of GREM1 expression within cohorts of oocytes showed that oocytes associated with the highest GREM1 expression were more likely to be transferred or cryopreserved than discarded (49 vs 33%, P<0.02), although the clinical pregnancy rate was not significantly different. This study demonstrates both the feasibility and difficulties of this method of analysis in the largest such group studied thus far. Novel relationships between BDNF expression and fertilisation were identified, and the potential value of GREM1 expression as a marker of embryo quality supports the further assessment of GREM1 analysis in the context of embryo selection.