“It is time to explore new avenues in fertility treatment and to establish a new standard: the EGP (Expected Gametes Performance)“, explains Nicolas Zech, Medical Director of the IVF Centers Prof. Zech in Bregenz. This is intended to allow the optimal creation of the couples’ individual profiles in order then to make accurate predictions regarding pregnancy rate and birthrate.
As founders of the EGP, the IVF Centers Prof. Zech have recently published an article on this issue in the Journal of Assisted Reproduction and Genetics, an internationally leading professional journal in the field of assisted reproductive medicine. At forthcoming conferences and future meetings, the optimum EGP parameters are to be discussed and, subsequently, to be defined together with interested experts and other IVF centers.
The individual counseling and treatment of couples seeking medical assistance to have a child with respect to their chances of giving birth to a healthy child is very complex, but is indeed crucial for the success of the treatment. Many factors such as age, hormonal profile, sperm quality and quality of the oocytes together with the stimulation protocol are taken into account in order to evaluate the individual pregnancy- and birthrate (“baby take home rate” / BTHR).
In order to estimate the couples’ chances to conceive, the currently valid standard is to group the women in so-called “responder”-groups (Low / Poor, Normal, High). Typically, these responder groups reflect the expected number of oocytes to be obtained for a specific age group after hormonal stimulation and egg retrieval (follicular puncture). However, a precise and uniform definition of the “responder”- groups and a holistic view of the different components that may have an impact on a fertility treatment are still missing. Sperm quality, fertilization rate as well as embryo developmental potential are NOT taken into consideration here. This leads to the following questions:
o Is it really sufficient to determine the number of oocytes in order to provide the patients with meaningful predictions in terms of success?
o Isn’t it time for a more holistic view by combining female AND male factors and considering them as a whole? The team of the IVF Centers Prof. Zech believes this to be a very positive attempt. YES, it is high time!
New standard taking into account blastocyst outcome
The aim is to introduce a new standard that is based on the number of blastocysts formed: the EGP (Expected Gametes Performance)“,(expected developmental potential of female and male gametes). To this end, the couples’ profiles were divided into different classifications: “below EGP”, “EGP” and “above EGP”. This includes, among others, the age of the patients, the specific stimulation protocol, the precise analysis of sperm quality (IMSI – Intracytoplasmic Morphological Selected sperm Injection), the fertilization rate as well as a specific protocol for blastocyst culture. In addition, the high quality standards in the laboratories of the IVF Centers Prof. Zech as well as the aseptic vitrification technique(optimum freezing) were used as relevant assessment parameters in the new standard EGP.
The aim is to provide orientation and a new approach of quality benchmarking allowing for improved prognosis. Moreover, the implementation of the EGP enables an objective evaluation of IVF clinics and their laboratories.
Blastocyst culture is of primordial importance
The first five days of embryonic development up to the blastocyst stage demonstrate quite clearly the interaction between maternal and paternal factors. Since the onset of the embryonic genome- and hence the influence of paternal factors – does only take place between the 2nd and the 3rd day of embryonic development, the EGP standard defines blastocyst outcome as a common denominator. It is quite common in fertility treatment that women being classified as “Low / Poor Responder” (1 – 8 oocytes retrieved) nonetheless achieve a good blastocyst outcome.
The focus is not on the number of oocytes retrieved, but the relevant factor for an individual prognosis is the blastocyst outcome. The following case studies from the IVF Centers Prof. Zech back up these considerations by giving details:
A 33-year-old female with a 42-year-old male partner, mild oligozoospermia, and secondary idiopathic sterility after biochemical pregnancy.
Cycle outcome: 7 oocytes obtained at pick-up; 6 mature oocytes; all 6 were fertilized (FR 100%); 5 good quality blastocysts on day 5; transfer of 2 blastocysts (Bl 5BA, Bl 4AB) and birth of one boy; and cryopreservation of 3 blastocysts.
Semen analysis: 2.6 ml; 11 Mio/ml; progressive motility: 57%; and IMSI report: 8% Class I, 51% Class II, and 41% Class III sperm.
A 35-year-old female with a 38-year-old male partner, normozoospermia, and primary sterility by obstruction of the fallopian tubes.
Cycle outcome: 11 oocytes obtained at pick-up; 10 mature oocytes; all fertilized (FR 100%); 1 blastocyst (fBl c); transfer of 1 blastocyst; no pregnancy in this cycle.
Semen analysis: 3.5 ml; 18.4 Mio/ml; progressive motility: 55%; and IMSI report: 0% Class I, 25% Class II, and 75% Class III sperm.
A 34-year-old female with a 37-year-old male partner, paraplegic, oligoasthenozoospermia, and primary sterility.
Cycle outcome: 16 oocytes obtained at pick-up; 13 mature oocytes; 12 fertilized (FR 92.3%); 5 blastocysts (4 good quality and 1 very low quality); transfer of 1 blastocyst (Bl 2AB) and birth of one healthy girl; and cryopreservation of 3 blastocysts.
Semen analysis: 1 ml; 2.5 Mio/ml; progressive motility: 5%; and IMSI report: 0% Class I, 11% Class II, and 89% Class III sperm.
Figure: Classification of cases A, B, and C into prognosis groups based on number of oocytes (poor responder: 1-8 oocytes, normal responder: 9-12 oocytes, or high responder: >12 oocytes), fertilization rate FR (%) classified as normal between 80-100%, or blastocyst outcome on day 5 (below EGP: 1-3 blastocysts, EGP: 4-5 blastocysts, or above EGP: >5 blastocysts).
AMH level (Anti-Mullerian hormone) used for prognosis
Public health insurance companies often request the AMH level to be determined Anti-Mullerian-Hormone can be detected in the woman’s blood). Based on this hormonal value, they intend to predict the expected number of oocytes and the chances of pregnancy.
Nicolas Zech says: “In our opinion, this is an inaccurate and unsatisfactory method and a poor prognosis parameter for the EGP. The focus today is no longer on the number of IVF cycles a woman may have to undergo to finally have a child, but is more an issue of how many children could result from just one cycle of ovarian stimulation!“