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Featured researches published by Ch. De Geyter.


Human Reproduction | 2016

Assisted reproductive technology in Europe, 2011: results generated from European registers by ESHRE

M. Kupka; T. D'Hooghe; Anna Pia Ferraretti; J. de Mouzon; Karin Erb; Jose Antonio Castilla; C. Calhaz-Jorge; Ch. De Geyter; V. Goossens

STUDY QUESTION The 15th European IVF-monitoring (EIM) report presents the results of treatments involving assisted reproductive technology (ART) initiated in Europe during 2011: are there any changes in the trends compared with previous years? SUMMARY ANSWER Despite some fluctuations in the number of countries reporting data, while the overall number of ART cycles has continued to increase year by year, the pregnancy rates in 2011 decreased slightly to those reported in 2010, and the number of transfers with multiple embryos (3+) and the multiple delivery rates declined. WHAT IS KNOWN ALREADY Since 1997, ART data in Europe have been collected and reported in 14 manuscripts, published in Human Reproduction. STUDY DESIGN, SIZE, DURATION Retrospective data collection of European ART data by the EIM Consortium for the European Society of Human Reproduction and Embryology (ESHRE); cycles started between 1 January and 31 December 2011 are collected on a yearly basis. The data are collected by National Registers, when existing, or on a voluntary basis by personal information. PARTICIPANTS/MATERIALS SETTING, METHODS From 33 countries (+2 compared with 2010), 1064 clinics reported 609 973 treatment cycles including: IVF 138 592, ICSI 298 918, frozen embryo replacement (FER) 129 693, egg donation (ED) 30 198, in vitro maturation 511, preimplantation genetic diagnosis/screening 6824 and frozen oocyte replacements 5237. European data on intrauterine insemination (IUI) using husband/partners semen (IUI-H) and donor semen (IUI-D) were reported from 861 IUI laboratories in 24 countries. A total of 174 390 IUI-H and 41 151 IUI-D cycles were included. MAIN RESULTS AND THE ROLE OF CHANCE In 17 countries where all clinics reported to the ART register, a total of 361 972 ART cycles were performed in a population of 285 million inhabitants, corresponding to 1269 cycles per million inhabitants. For all IVF cycles, the clinical pregnancy rates per aspiration and per transfer were stable with 29.1 and 33.2%, respectively, and for ICSI, the corresponding rates also were stable with 27.9 and 31.8%, respectively. In FER cycles, the pregnancy rate per thawing increased to 21.3% if compared with previous years. In ED cycles, the pregnancy rate per fresh transfer decreased to 45.8% (47.4% in 2010) and increased to 33.6% (33.3% in 2010) per thawed transfer. The delivery rate after IUI-H decreased to 8.3 (8.9 in 2010), and to 12.2% (13.8% in 2010) after IUI-D. In IVF and ICSI cycles, 1, 2, 3 and 4+ embryos were transferred in 27.5, 56.7, 14.5 and 1.3% of cycles, respectively. The proportions of singleton, twin and triplet deliveries after IVF and ICSI (added together) were 80.8, 18.6 and 0.6%, respectively, resulting in a total multiple delivery rate of 19.2% compared with 20.6% in 2010, 20.2% in 2009, 21.7% in 2008, 22.3% in 2007 and 20.8% in 2006. In FER cycles, the multiple delivery rate was 13.2% (12.8% twins and 0.4% triplets). Twin and triplet delivery rates associated with IUI cycles were 9.7/0.6% and 7.3/0.3%, following IUI-H and IUI-D treatment, respectively. LIMITATIONS, REASONS FOR CAUTION The method of reporting varies among countries, and registers from a number of countries have been unable to provide some of the relevant data such as initiated cycles and deliveries. As long as data are incomplete and generated through different methods of collection, results should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS The 15th ESHRE report on ART shows a continuing expansion of the number of treatment cycles in Europe, with more than 600 000 cycles reported in 2011. Since 2006, the proportion of IVF to ICSI cycles has reached a plateau after a small decrease in 2009. Pregnancy and delivery rates after IVF remained relatively stable compared with 2010 and 2009. The pregnancy rate per aspiration in ICSI cycles declined for the first time by 0.9%. The multiple delivery rate is lower than ever before. STUDY FUNDING/COMPETING INTERESTS The study had no external funding; all costs are covered by ESHRE. There are no competing interests.


European Journal of Clinical Investigation | 2006

Menstrual cycle symptoms are associated with changes in low‐grade inflammation

J. J. Puder; C. A. Blum; B. Mueller; Ch. De Geyter; L. Dye; U. Keller

Background  A close link between mood, low‐grade inflammation and obesity has been demonstrated even in healthy subjects. We investigated the relationship between changes in physical and psychological symptoms and inflammatory markers during the menstrual cycle both in normal weight and in overweight women.


Molecular Human Reproduction | 2014

Species-specific differences in follicular antral sizes result from diffusion-based limitations on the thickness of the granulosa cell layer

M. Bächler; Denis Menshykau; Ch. De Geyter; Dagmar Iber

The size of mature oocytes is similar across mammalian species, yet the size of ovarian follicles increases with species size, with some ovarian follicles reaching diameters>1000-fold the size of the enclosed oocyte. Here we show that the different follicular sizes can be explained with diffusion-based limitations on the thickness of the hormone-secreting granulosa layer. By analysing published data on human follicular growth and granulosa cell expansion during follicular maturation we find that the 4-fold increase of the antral follicle diameter is entirely driven by an increase in the follicular fluid volume, while the thickness of the surrounding granulosa layer remains constant at ∼45±10 µm. Based on the measured kinetic constants, the model reveals that the observed fall in the gonadotrophin concentration from peripheral blood circulation to the follicular antrum is a result of sequestration in the granulosa. The model further shows that as a result of sequestration, an increased granulosa thickness cannot substantially increase estradiol production but rather deprives the oocyte from gonadotrophins. Larger animals (with a larger blood volume) require more estradiol as produced by the ovaries to down-regulate follicle-stimulating hormone-secretion in the pituitary. Larger follicle diameters result in larger follicle surface areas for constant granulosa layer thickness. The reported increase in the follicular surface area in larger species indeed correlates linearly both with species mass and with the predicted increase in estradiol output. In summary, we propose a structural role for the antrum in that it determines the volume of the granulosa layer and thus the level of estrogen production.


Human Reproduction | 2016

Data collection systems in ART must follow the pace of change in clinical practice

Ch. De Geyter; Christine Wyns; E. Mocanu; J. de Mouzon; C. Calhaz-Jorge

In assisted reproductive technology (ART), quality control necessitates the collection of outcome data and occurring complications. Traditional quality assurance is based on data derived from single ART centres and more recently from national registries, both recording outcome parameters during well-defined observation periods. Nowadays, ART is moving towards much more diverse approaches, with sequential activities including short- or long-term freezing of gametes, gonadal tissues and embryos, and cross-border reproductive care. Hence, long-term cumulative treatment rates and an international approach are becoming a necessity. We suggest the initiation of an easy access European Reproductive Coding System, through which each ART recipient is allocated a unique reproductive care code. This code would identify individuals (and reproductive material) during case to case data reporting to national ART data collecting institutions and to a central European ART monitoring agency. For confidentiality reasons, the identity of the individuals should remain with the local ART provider. This way, cumulative and fully reliable reproductive outcome data can be constructed with follow-up over prolonged time periods.


Human Reproduction | 2018

ART in Europe, 2014: results generated from European registries by ESHREThe European IVF-monitoring Consortium (EIM) for the European Society of Human Reproduction and Embryology (ESHRE)

Ch. De Geyter; C. Calhaz-Jorge; M. S. Kupka; Christine Wyns; E. Mocanu; T. Motrenko; G. Scaravelli; J Smeenk; S Vidakovic; Goossens; Orion Gliozheni; Heinz Strohmer; Obruca; Strohmer Partnerschaft Goldenes Kreuz-Kinderwunschzentrum; Elena Petrovskaya; Oleg Tishkevich; Kris Bogaerts; Devleta Balic; Sanja Sibincic; Irena Antonova; Hrvoje Vrcic; Dejan Ljiljak; Michael Pelekanos; Karel Rezabek; Jitka Markova; Josephine Lemmen; Deniss Sõritsa; Mika Gissler; Aila Tiitinen; Dominique Royere

STUDY QUESTION What are the European trends and developments in ART and IUI in 2014 as compared to previous years? SUMMARY ANSWER The 18th ESHRE report on ART shows a continuing expansion of both treatment numbers in Europe and more variability in treatment modalities resulting in a rising contribution to the birth rates in most participating countries. WHAT IS KNOWN ALREADY Since 1997, ART data generated by national registries have been collected, analysed by the European IVF-monitoring (EIM) Consortium and reported in 17 manuscripts published in Human Reproduction. STUDY DESIGN, SIZE, DURATION Continuous collection of European data by the EIM for ESHRE. The data for treatments performed in 2014 between 1 January and 31 December in 39 European countries were provided by national registries or on a voluntary basis by clinics or professional societies. PARTICIPANTS/MATERIALS, SETTING, METHODS From 39 countries and 1279 institutions offering ART services, a total of 776 556 treatment cycles, involving 146 148 with IVF, 362 285 with ICSI, 192 027 with frozen embryo replacement (FER), 15 894 with PGT, 56 516 with egg donation (ED), 292 with IVM and 3404 with frozen oocyte replacement (FOR) were reported. European data on IUI using husband/partners semen (IUI-H) and donor semen (IUI-D) were reported from 1364 institutions offering IUI in 26 countries and 21 countries, respectively. A total of 120 789 treatments with IUI-H and 49 163 treatments with IUI-D were included. MAIN RESULTS AND THE ROLE OF CHANCE In 14 countries (17 in 2013), where all institutions contributed to their respective national registers, a total of 291 235 treatment cycles were performed in a population of ~208 million inhabitants, corresponding to 1925 cycles per million inhabitants (range: 423-2978 per million inhabitants). After treatment with IVF the clinical pregnancy rates (PR) per aspiration and per transfer were marginally higher in 2014 than in 2013, at 29.9 and 35.8% versus 29.6 and 34.5%, respectively. After treatment with ICSI the PR per aspiration and per transfer were also higher than those achieved in 2013 (28.4 and 35.0% versus 27.8 and 32.9%, respectively). After FER with own embryos the PR continued to rise, from 27.0% in 2013 to 27.6% in 2014. After ED a similar trend was observed with PR reaching 50.3% per fresh transfer (49.8% in 2013) and 48.7% for FOR (46.4% in 2013). The delivery rates (DR) after IUI remained stable at 8.5% after IUI-H (8.6% in 2013) and at 11.6% after IUI-D (11.1% in 2013). In IVF and ICSI together, 1, 2, 3 and ≥4 embryos were transferred in 34.9, 54.5, 9.9 and in 0.7% of all treatments, respectively (corresponding to 31.4%, 56.3, 11.5% and 1% in 2013). This evolution in embryo transfer strategy in both IVF and ICSI resulted in a singleton, twin and triplet DR of 82.5, 17.0 and 0.5%, respectively (compared to 82.0, 17.5 and 0.5%, respectively, in 2013). Treatments with FER in 2014 resulted in a twin and triplet DR of 12.4 and 0.3%, respectively (versus 12.5 and 0.3% in 2013). Twin and triplet DR after IUI were 9.5 and 0.3%, respectively, after IUI-H (in 2013:9.5 and 0.6%) and 7.7 and 0.3% after IUI-D (in 2013: 7.5 and 0.3%). LIMITATION, REASONS FOR CAUTION The method of data collection and reporting varies among European countries. The EIM receives aggregated data from various countries with variable levels of completeness. Registries from a number of countries have failed to provide adequate data about the number of initiated cycles and deliveries. As long as incomplete data are provided, the results should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS The 18th ESHRE report on ART shows a continuing expansion of treatment numbers in Europe. The number of treatments reported, the variability in treatment modalities and the rising contribution to the birth rates in most participating countries point towards the increasing impact of ART on reproduction in Europe. Being the largest data collection on ART, the report gives detailed information about ongoing developments in the field. STUDY FUNDING/COMPETING INTEREST(S) The study has no external funding and all costs are covered by ESHRE. There are no competing interests.


Human Reproduction | 2000

Clustering of male infertility in the families of couples treated with intracytoplasmic sperm injection

Dieter Meschede; B. Lemcke; Hermann M. Behre; Ch. De Geyter; Eberhard Nieschlag; Jürgen Horst


Human Reproduction | 1992

Interdependent influence of follicular fluid oestradiol concentration and motility characteristics of spermatozoa on in-vitro fertilization results

Ch. De Geyter; M. De Geyter; H. P. G. Schneider; Eberhard Nieschlag


Human Reproduction | 1994

Endocrinology: Pulsatile subcutaneous versus bolus intramuscular gonadotrophin administration after pituitary suppression with a long-acting gonadotrophin-releasing hormone analogue: a controlled prospective study

Ch. De Geyter; M. De Geyter; Manuela Simoni; Eduardo Castro; Monika Bals-Pratsch; Eberhard Nieschlag; H. P. G. Schneider


Human Reproduction | 1999

P-259. Characterization of an immortalized human granulosa cell line (COV434) for the study of the development of ovarian follicles in vitro

Ch. De Geyter; Hong Zhang; Marielle Vollmer; M. De Geyter; Peter Miny; Wolfgang Holzgreve


Human Reproduction | 1997

P-057. Computation of sperm motion for the prediction of fertilization in vitro of cumulus-enclosed human oocytes

Ch. De Geyter; M. De Geyter; B. Koppers; Eberhard Nieschlag

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Christine Wyns

Cliniques Universitaires Saint-Luc

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