IMPROVING IVF SUCCESS: ADVANCED TECHNIQUES FOR EMBRYO SELECTION
Counseling couples on their chances to conceive is complex and difficult. Many single parameters (e.g. age, hormone profiles, sperm parameters, and oocyte quality with individual stimulation protocols, the “expected gametes performance” EGP-Index, possibility for cryopreservation of surplus embryos) are taken into account to evaluate individual take-home baby rates or cumulative pregnancy rates.
Important impacts can also be anticipated from previous attempts. Based on the number of developing follicles and the number of retrieved oocytes, patients are grouped into different types of responders as follows: “normal responder” if the expected number of oocytes for a specific age group is reached, or “low responder” or “high responder” if the number of oocytes is below or above this threshold, respectively. However, because this terminology only reflects ovarian reserves and response to hormonal stimulation, it is questionable as to whether it is tangible enough to provide the patient with meaningful predictions.
Furthermore, there are many other parameters that can be included for analysis, such as an increasing number of additional hormonal and immunological values, antral follicle count, detailed morphological analysis of the oocytes, 2PN scoring, sperm fine morphological conspicuities detected by motile sperm organelle morphology examination (MSOME), and DNA-integrity of the sperm nucleus. Morphokinetic analysis provides insights into fertilization patterns and developmental kinetics. In the future, techniques at the molecular level, such as proteomics, metabolomics, genomics or transcriptomics, will be introduced as routine aspects in development evaluations. Uterine and endometrial factors, important for implantation and further potential for embryo development, have to be taken into account as well and are evaluated by ultrasound or with hysteroscopy. If pathologies such as submucous myomas, polyps, adhesions, adenomyosis are suspected or diagnosed, they should be treated accordingly before starting IVF. In the end, we have a large pool of information that has to be combined to create a complete picture on individual success rates.
With more than 30 years of experience in ART and 15 years of experience in blastocyst culture, having performed over 30.000 IVF cycles with blastocyst transfer, and experience in implementing new technologies, such as intracytoplasmic morphological selected sperm injection (IMSI), aseptic vitrification, accumulation-cycles to mention just a few, we think it is now time to change our way of thinking and counseling patients. During the first five days, embryos develop as a result of a harmonic interplay between maternal and early as well as late paternal factors. One crucial step is onset of the embryonic genome on day two to day three. New techniques and sophisticated applied methods for optimizing the number of developing embryos to the blastocyst stage, such as oocyte activation, IMSI, application of different culture media, microfluidics, and innovative, well adapted incubators, are all reflected in these parameters. The “product” of this interplay is the blastocyst, which dissolves the entanglement of individual maternal and paternal parameters.
In ART, the primary goal is to achieve a viable and ongoing pregnancy as rapidly and safely for the patient as possible. The current question should be ‘How many live births are obtained from one stimulation cycle’ rather than ‘How many IVF cycles are necessary for a patient to give birth to one baby’. The vision is a “normal” response in terms of hyperstimulation after follicular superovulation, preventing women from experiencing symptoms of severe hyperstimulation syndrome, with a target take-home baby rate of 100%.