Nikolaos P. Polyzos

Prof. Dr. Nikolaos P. Polyzos

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 February 2020 in Human Reproduction Open
Verified
Journal Article
Open access
TSThe ESHRE Guideline Group on Ovarian Stimulation
The ESHRE Guideline Group on Ovarian Stimulation
EBErnesto Bosch
Ernesto Bosch
SBSimone Broer
Simone Broer
GGGeorg Griesinger
Georg Griesinger
MGMichael Grynberg
Michael Grynberg
FBFrank Broekmans
Frank Broekmans
STUDY QUESTION: What is the recommended management of ovarian stimulation, based on the best available evidence in the literature?SUMMARY ANSWER: The guideline development group formulated 84 recommendations answering 18 key questions on ovarian stimulation.WHAT IS KNOWN ALREADY: Ovarian stimulation for IVF/ICSI has been discussed briefly in the National Institute for Health and Care Excellence guideline on fertility problems, and the Royal Australian and New Zealand College of Obstetricians and Gynaecologist has published a statement on ovarian stimulation in assisted reproduction. There are, to our knowledge, no evidence-based guidelines dedicated to the process of ovarian stimulation.STUDY DESIGN, SIZE, DURATION: The guideline was developed according to the structured methodology for development of ESHRE guidelines. After formulation of key questions by a group of experts, literature searches and assessments were performed. Papers published up to 8 November 2018 and written in English were included. The critical outcomes for this guideline were efficacy in terms of cumulative live birth rate per started cycle or live birth rate per started cycle, as well as safety in terms of the rate of occurrence of moderate and/or severe ovarian hyperstimulation syndrome (OHSS).PARTICIPANTS/MATERIALS, SETTING, METHODS: Based on the collected evidence, recommendations were formulated and discussed until consensus was reached within the guideline group. A stakeholder review was organized after finalization of the draft. The final version was approved by the guideline group and the ESHRE Executive Committee.MAIN RESULTS AND THE ROLE OF CHANCE: The guideline provides 84 recommendations: 7 recommendations on pre-stimulation management, 40 recommendations on LH suppression and gonadotrophin stimulation, 11 recommendations on monitoring during ovarian stimulation, 18 recommendations on triggering of final oocyte maturation and luteal support and 8 recommendations on the prevention of OHSS. These include 61 evidence-based recommendations—of which only 21 were formulated as strong recommendations—and 19 good practice points and 4 research-only recommendations. The guideline includes a strong recommendation for the use of either antral follicle count or anti-Müllerian hormone (instead of other ovarian reserve tests) to predict high and poor response to ovarian stimulation. The guideline also includes a strong recommendation for the use of the GnRH antagonist protocol over the GnRH agonist protocols in the general IVF/ICSI population, based on the comparable efficacy and higher safety. For predicted poor responders, GnRH antagonists and GnRH agonists are equally recommended. With regards to hormone pre-treatment and other adjuvant treatments (metformin, growth hormone (GH), testosterone, dehydroepiandrosterone, aspirin and sildenafil), the guideline group concluded that none are recommended for increasing efficacy or safety.LIMITATIONS, REASON FOR CAUTION: Several newer interventions are not well studied yet. For most of these interventions, a recommendation against the intervention or a research-only recommendation was formulated based on insufficient evidence. Future studies may require these recommendations to be revised.WIDER IMPLICATIONS OF THE FINDINGS: The guideline provides clinicians with clear advice on best practice in ovarian stimulation, based on the best evidence available. In addition, a list of research recommendations is provided to promote further studies in ovarian stimulation.STUDY FUNDING/COMPETING INTEREST(S): The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings, with the literature searches and with the dissemination of the guideline. The guideline group members did not receive payment. F.B. reports research grant from Ferring and consulting fees from Merck, Ferring, Gedeon Richter and speaker’s fees from Merck. N.P. reports research grants from Ferring, MSD, Roche Diagnositics, Theramex and Besins Healthcare; consulting fees from MSD, Ferring and IBSA; and speaker’s fees from Ferring, MSD, Merck Serono, IBSA, Theramex, Besins Healthcare, Gedeon Richter and Roche Diagnostics. A.L.M reports research grants from Ferring, MSD, IBSA, Merck Serono, Gedeon Richter and TEVA and consulting fees from Roche, Beckman-Coulter. G.G. reports consulting fees from MSD, Ferring, Merck Serono, IBSA, Finox, Theramex, Gedeon-Richter, Glycotope, Abbott, Vitrolife, Biosilu, ReprodWissen, Obseva and PregLem and speaker’s fees from MSD, Ferring, Merck Serono, IBSA, Finox, TEVA, Gedeon Richter, Glycotope, Abbott, Vitrolife and Biosilu. E.B. reports research grants from Gedeon Richter; consulting and speaker’s fees from MSD, Ferring, Abbot, Gedeon Richter, Merck Serono, Roche Diagnostics and IBSA; and ownership interest from IVI-RMS Valencia. P.H. reports research grants from Gedeon Richter, Merck, IBSA and Ferring and speaker’s fees from MSD, IBSA, Merck and Gedeon Richter. J.U. reports speaker’s fees from IBSA and Ferring. N.M. reports research grants from MSD, Merck and IBSA; consulting fees from MSD, Merck, IBSA and Ferring and speaker’s fees from MSD, Merck, IBSA, Gedeon Richter and Theramex. M.G. reports speaker’s fees from Merck Serono, Ferring, Gedeon Richter and MSD. S.K.S. reports speaker’s fees from Merck, MSD, Ferring and Pharmasure. E.K. reports speaker’s fees from Merck Serono, Angellini Pharma and MSD. M.K. reports speaker’s fees from Ferring. T.T. reports speaker’s fees from Merck, MSD and MLD. The other authors report no conflicts of interest.Disclaimer: This guideline represents the views of ESHRE, which were achieved after careful consideration of the scientific evidence available at the time of preparation. In the absence of scientific evidence on certain aspects, a consensus between the relevant ESHRE stakeholders has been obtained.Adherence to...


25 September 2023 in Human Reproduction
Verified
Journal Article
Open access
PDF file
EGESHRE Add-ons working group
ESHRE Add-ons working group
KLK Lundin
K Lundin
JBJ G Bentzen
J G Bentzen
GBG Bozdag
G Bozdag
TET Ebner
T Ebner
APA Pinborg
A Pinborg
STUDY QUESTION: Which add-ons are safe and effective to be used in ART treatment? SUMMARY ANSWER: Forty-two recommendations were formulated on the use of add-ons in the diagnosis of fertility problems, the IVF laboratory and clinical management of IVF treatment. WHAT IS KNOWN ALREADY: The innovative nature of ART combined with the extremely high motivation of the patients has opened the door to the wide application of what has become known as ‘add-ons’ in reproductive medicine. These supplementary options are available to patients in addition to standard fertility procedures, typically incurring an additional cost. A diverse array of supplementary options is made available, encompassing tests, drugs, equipment, complementary or alternative therapies, laboratory procedures, and surgical interventions. These options share the common aim of stating to enhance pregnancy or live birth rates, mitigate the risk of miscarriage, or expedite the time to achieving pregnancy. STUDY DESIGN, SIZE, DURATION: ESHRE aimed to develop clinically relevant and evidence-based recommendations focusing on the safety and efficacy of add-ons currently used in fertility procedures in order to improve the quality of care for patients with infertility. PARTICIPANTS/MATERIALS, SETTING, METHODS: ESHRE appointed a European multidisciplinary working group consisting of practising clinicians, embryologists, and researchers who have demonstrated leadership and expertise in the care and research of infertility. Patient representatives were included in the working group. To ensure that the guidelines are evidence-based, the literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, recommendations were based on the professional experience and consensus of the working group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 46 independent international reviewers. A total of 272 comments were received and incorporated where relevant. MAIN RESULTS AND THE ROLE OF CHANCE: The multidisciplinary working group formulated 42 recommendations in three sections; diagnosis and diagnostic tests, laboratory tests and interventions, and clinical management. LIMITATIONS, REASONS FOR CAUTION: Of the 42 recommendations, none could be based on high-quality evidence and only four could be based on moderate-quality evidence, implicating that 95% of the recommendations are supported only by low-quality randomized controlled trials, observational data, professional experience, or consensus of the development group. WIDER IMPLICATIONS OF THE FINDINGS: These guidelines offer valuable direction for healthcare professionals who are responsible for the care of patients undergoing ART treatment for infertility. Their purpose is to promote safe and effective ART treatment, enabling patients to make informed decisions based on realistic expectations. The guidelines aim to ensure that patients are fully informed about the various treatment options available to them and the likelihood of any additional treatment or test to improve the chance of achieving a live birth. STUDY FUNDING/COMPETING INTEREST(S): All costs relating to the development process were covered from ESHRE funds. There was no external funding of the development process or manuscript production. K.L. reports speakers fees from Merck and was part of a research study by Vitrolife (unpaid). T.E. reports consulting fees from Gynemed, speakers fees from Gynemed and is part of the scientific advisory board of Hamilton Thorne. N.P.P. reports grants from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare, speakers fees from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare. S.R.H. declares being managing director of Fertility Europe, a not-for-profit organization receiving financial support from ESHRE. I.S. is a scientific advisor for and has stock options from Alife Health, is co-founder of IVFvision LTD (unpaid) and received speakers’ fee from the 2023 ART Young Leader Prestige workshop in China. A.P. reports grants from Gedeon Richter, Ferring Pharmaceuticals and Merck A/S, consulting fees from Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos and Merck A/S, speakers fees from Gedeon Richter, Ferring Pharmaceuticals, Merck A/S, Theramex and Organon, travel fees from Gedeon Richter. The other authors disclosed no conflicts of interest. DISCLAIMER: This Good Practice Recommendations (GPRs) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation. ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or bedeemedinclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results.Theydo not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type. Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.

13 May 2020 in Reproductive Biology and Endocrinology
Verified
Journal Article
Open access
PDF file
OGon behalf of the POSEIDON (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) group
on behalf of the POSEIDON (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) group
CACarlo Alviggi
Carlo Alviggi
Sandro EstevesSandro Esteves
Sandro Esteves
Raoul OrvietoRaoul Orvieto
Raoul Orvieto
ACAlessandro Conforti
Alessandro Conforti
FUFilippo M. Ubaldi
Filippo M. Ubaldi
The prolonged lockdown of health services providing high-complexity fertility treatments –as currently recommended by many reproductive medicine entities– is detrimental for society as a whole, and infertility patients in particular. Globally, approximately 0.3% of all infants born every year are conceived using assisted reproductive technology (ART) treatments. By contrast, the total number of COVID-19 deaths reported so far represents approximately 1.0% of the total deaths expected to occur worldwide over the first three months of the current year. It seems, therefore, that the number of infants expected to be conceived and born –but who will not be so due to the lockdown of infertility services– might be as significant as the total number of deaths attributed to the COVID-19 pandemic. We herein propose remedies that include a prognostic-stratification of more vulnerable infertility cases in order to plan a progressive restart of worldwide fertility treatments. At a time when preventing complications and limiting burdens for national health systems represent relevant issues, our viewpoint might help competent authorities and health care providers to identify patients who should be prioritized for the continuation of fertility care in a safe environment.

29 September 2018 in Human Reproduction
Verified
Journal Article
Open access
PDF file
MDMarta Devesa
Marta Devesa
RTRosa Tur
Rosa Tur
IRIgnacio Rodriguez
Ignacio Rodriguez
BCBuenaventura Coroleu
Buenaventura Coroleu
FMFrancisca Martínez
Francisca Martínez
NPNikolaos P. Polyzos
Nikolaos P. Polyzos
Is there any relationship between the number of oocytes retrieved and cumulative live birth rates (CLBRs) in women of advanced age? CLBRs increase with the number of oocytes retrieved in women of advanced reproductive age up to 41 years old, the added value is minimal in women more than 41 years and futile in women 44 years or older. CLBR is actually the most relevant outcome of IVF from patients’ perspective. There are several studies that have analysed CLBR’s but some of them have included several stimulation cycles, others have not included the frozen embryo transfers (FETs) in their analysis and none has focused on women of advanced reproductive age. We aimed to assess CLBR in women ≥38 years after a single stimulation cycle plus the subsequent frozen embryo transfers. This is a retrospective analysis carried out in a University-affiliated tertiary centre between January 2000 and December 2013. Overall, 4570 infertile women aged ≥38 years who underwent their first cycle in our centre were included. Patients were categorized in four age-groups: 38–39 years (G1 = 1875 cycles), 40–41 years (G2 = 1380 cycles), 42–43 years (G3 = 833 cycles) and ≥44 years (G4 = 482 cycles). CLBR’s were evaluated by adding the pregnancies and live births achieved in the FET’s to the ones obtained in the fresh cycle. In order to find out the actual effect of the number of oocytes retrieved in these patients, a predictive model of CLBR according to age and oocyte yield was built. CLBRs significantly decrease with increasing age among women ≥38 years of age, with the most prominent and clinically relevant decline observed at 42–43 years old, and clear evidence for futility in women aged ≥44 years (25.9% at 38–39 years, 16.4% at 40–41 years, 7% at 42–43 years and 1.2% from 44 years onwards). The higher the number of oocytes retrieved, the higher the CLBR; however, this is more evident up to 41 years old and no clear benefit is observed from 44 years and beyond. Limitations are related to the retrospective nature of the study; however, no significant differences were observed in the treatment protocols used. Other potential limitations could be the fact that embryo cryopreservation was carried out with slow freezing in 80% of cases and that a small proportion of patients still have frozen embryos; nevertheless, we do not expect a relevant impact of these issues as slow freezing showed excellent results that did not differ significantly compared to vitrification and, on the other hand, the extra benefit coming from the FETs was very limited. The number of oocytes retrieved is significantly associated with CLBR also in women of advanced reproductive age. However, the added benefit appears to be restricted mainly in women up to 41 years old. Women over 43 do not experience any benefit in CLBR irrespective of the number of oocytes retrieved, and thus should be discouraged from doing an IVF cycle with their own oocytes; for the other age-groups, recommendations should be given considering the age and the expected ovarian response. None. NA

27 July 2019 in Journal of Assisted Reproduction and Genetics
Verified
Journal Article
Closed access
PDF file
ANAna Raquel Neves
Ana Raquel Neves
MDMarta Devesa
Marta Devesa
FMFrancisca Martínez
Francisca Martínez
SMSandra Garcia Martinez
Sandra Garcia Martinez
IRIgnacio Rodriguez
Ignacio Rodriguez
BCBuenaventura Coroleu
Buenaventura Coroleu