Once again the biggest event in the field of assisted reproduction, ESHRE, has taken place. More than 12 000 delegates gathered in bustling Barcelona for updates on the latest science and of course to meet with old and new friends. As usual the Vitrolife team has put together some reflections and updates on what is going on in our community. We also provide a new chance to watch our symposium.
Blastomere movement an indicator for clinical pregnancy rates
Ohata et al. (O-113) described three different types of blastomere movements occurring after the first cytokinesis and showed a difference in incidence, developmental capability and embryo quality between the three categories. Through time-lapse analysis their data revealed an association of the duration of blastomere movements with the resulting clinical pregnancy rates.
New data support direct cleavage is associated with decreased clinical outcome
The direct (or rapid) cleavage of one blastomere into more daughter cells in cleavage stage embryos is a phenomenon that has been investigated heavily in the last years. The phenomenon is only visible through time-lapse monitoring and has been reported to be associated with significantly decreased blastocyst formation and clinical outcome rates, more severely so when the direct cleavage happens early or multiple times during the cleavage stage [1, 2]. Data from Montgomery et al. (O-114) further confirms these observations with an incidence rate of direct cleavage of 11% distributed evenly on developmental stages of occurrence and also found that older patients were more affected of this irregular developmental phenomenon. The molecular-level mechanisms underlying direct cleavage of blastomeres was investigated by Zaninovic et al (O-005) who found that the multi-polar spindles causing the irregular chromosomal division may form as a result of disrupted PLK4 gene regulation.
Embryos can self-correct through partial compaction
Lagalla et al. (O-116) further investigates the ability of embryos with abnormal development to possibly self-correct through partial compaction. Their data showed that with an incidence rate of 64%, partial compaction is not uncommon, and their observations revealed that partial compaction can happen through either exclusion or extrusion of cells. Their data further showed that the latter is often associated with lysis of the extruded cells.
The exclusion of cells before compaction was shown to be more predominant in younger women and data indicated that the embryos from young patients that exclude cells before compaction result in the lowest aneuploidy rate, which further supports the hypothesis of partial compaction as an embryo self-repair mechanism, at least when it happens through exclusion of cells.
Time-lapse videos a positive patient communication tool
Hickman (O-228) pointed out that working efficiently with time-lapse in a clinical setting is most effectively done with a defined protocol for the assessment and evaluation processes. Efficient assessment comes from standardising embryo scoring within the laboratory and efficient evaluation is best achieved through working with time-lapse-based models which can be either universal or clinic-specific.
The patient experiences of having access to time-lapse videos of their embryos have been reported to be both positive and desirable . Through analysis of time-lapse user survey results Hickman found that the communication towards the patient differed widely across clinics with respect to both level of access and time of access.
Spindle morphology possible indicator for embryo ploidy
Non-invasive genetic testing methods are of interest and Tilia et al (O-029) investigated if spindle morphology can be predictive for embryo ploidy. They found that oocytes with normal meiotic spindle morphology are associated with a significantly higher rate of blastocyst euploidy.
New insight on the effect of oxygen deprivation
Seidler et al. at Boston IVF (O-030) continues the work on using autofluoresence to investigate embryo metabolism. They presented new and interesting work showing effects of oxygen deprivation on embryo development. They showed that depending on developmental stage, mouse embryos displayed distinct metabolic responses to oxygen deprivation.
Health of children born after ART – still a hot topic
Health of children born after ART was discussed in different sessions during the congress. Marconi et al (O-067), using the UK data showed that birth weight was not different when embryos were transferred day 3 or day 5. Previous findings showing negative effects on singletons born following transfer of multiple embryos was confirmed using the same large UK database (Kamath et al. O-070). A large Australian study by Fernandez et al (O-069) indicated that children born after cryopreservation may have less risk of urogenital defects.
During the first keynote session, the findings on semen quality of young ICSI adults were presented (O-001). The results from a small group indicated a lower semen quantity and quality in young adults born after ICSI for male infertility in their fathers. Results can however not be generalised to all ICSI offspring because the indications for ICSI have nowadays been extended and ICSI is also being performed with non-ejaculated sperm and reported differences may thus either decrease or increase.
WHO and infertility
The position of WHO regarding infertility was discussed during a session with invited WHO representatives. WHO endorses that infertility has to be addressed and work is ongoing to improve the views on the need for fertility treatment globally. Willem Ombelet presented the latest results on his work to develop a simplified IVF procedure. While results are promising, there are challenges to make this a more generalised procedure
New protocol for IVM show promising results
Sanchez et al (O-133) presented results from an optimised IVM protocol, with focus on patients with PCS/PCOS. The techniques involves an additional step using a peptide during a pre-maturation phase. Results are promising and seem to increase the efficiency of IVM.
Degree of blastocyst collapse correlated to outcome
A multicentre study looking at blastocyst collapse patterns ( O-136 presented by R Sciorio) showed that occurrence and degree of blastocyst collapse was strongly correlated with implantation and ongoing pregnancy rate.
Errors in IVF – do they happen?
A whole session was dedicated to the question “errors in IVF – do they occur and how many” (O-150). The session included a talk on a clinicians views and one on laboratory aspects presented by M.j. De Los Santos. For the latter, a recent publication from L Rienzi was used as the basis for the talk .
Big data in IVF support patient treatment
Analysing large datasets to predict outcomes is not new, but now the field of IVF is searching for algorithms that help patients, for example, understand their chance of success. Balachandren et al (O-194) presented the possibility of predicting the chance of live birth after a single cycle and transfer of all the resulting embryos. The analysis showed that women with a live birth had a lower age and FSH level and higher AMH and antral follicle count. Validation on a subsequent small set of patients indicated that the model was able to correctly predict 96% of couples who had a live birth within their cycle.
Correa et al (O-195) demonstrated that patient parameters and their potential stimulation protocol can help determine, with high reliability, the number of cumulus oocyte complexes and MII oocytes retrieved from a patient’s first IVF cycle.
Sfontouris et al (O-197) compared different live birth prediction models using a large U.K database. As mentioned by the presenter one challenge is that these large databases often lack many patient parameters. It is also important not to forget the potential impact of changes within the stimulation protocol or laboratory conditions.
Epigenetic changes and what can cause them
In his talk on epigenetic changes by stimulation and culture (O-273) Arne Sunde was careful to not isolate specific products or aspects of an IVF treatment as a possible cause for epigenetic changes. Although culture media can have an effect, the impact of other aspects such as oxygen and stimulation have to be considered. He also talked about the combined effects from different parameters and that very little is known about possible long term effects.
The importance of a correct temperature during embryo culture and handling
Ronny Janssens presented work on temperature measurements (O-272). Although the embryo is highly adaptable, temperature can impact gamete and embryo function and meiotic spindle stability. He discussed the complexity of performing temperature measurements and included recent studies on effects of temperature during culture on embryo development and pregnancy.
- Rubio, I., et al., Limited implantation success of direct-cleaved human zygotes: a time-lapse study. Fertil Steril, 2012. 98(6): p. 1458-63.
- Zhan, Q., et al., Direct Unequal Cleavages: Embryo Developmental Competence, Genetic Constitution and Clinical Outcome. PLoS One, 2016. 11(12): p. e0166398.
- A. Bladh Blomquist, I.L.S., R. Samir, A. B. Engström, S. Nilsson, A. K. Lindh, G. Westlander, S. Larsson, T. Hardarson, J. Hreinsson, Patients experience of viewing time-lapse sequences, a prospective survey study. Hum Reprod, 2015. 30(suppl 1): p. i443.
- Rienzi L, et at., Comprehensive protocol of traceability during IVF: the result of a multicentre failure mode and effect analysis. Hum Reprod. 2017 Aug 1;32(8):1612-1620.
Watch our Scientific Symposium "How to optimise the efficiency and outcomes of your IVF procedures"
This year we had the pleasure of listening to Dr. Kan from Australia talking about his experience using the Sense needle to optimise the oocyte retrieval procedure both for him and his patients. Prof. Gardner gave insights into protecting the embryo to ensure maximum developmental potential, by using antioxidants in the culture media and using a time-lapse system during culture. Dr. Katz-Jaffe deepened our knowledge about mosaicism and also provided advice on how to reduce it by paying attention to the laboratory procedures.
If you missed the symposium or simply want to see it again, just click below.
Topics: IVF community insights