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Dive into the research topics where Bernard Lejeune is active.

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Featured researches published by Bernard Lejeune.


Archive | 2012

Intracytoplasmic Morphologically Selected Sperm Injection

Pierre Vanderzwalmen; Magnus Bach; Batsuren Baramsai; Anton Neyer; Delf Schwerda; Astrid Stecher; Barbara Wirleitner; Martin Zintz; Bernard Lejeune; Sabine Vanderzwalmen; Nino Guy Cassuto; Mathias H. Zech; Nicolas H. Zech

Intracytoplasmic morphologically selected sperm injection (IMSI) is now a reality in ART practice but still with a lot of questions regarding (1) the terminology of vacuoles, their classification, their location on the sperm head, and their origin and meaning; (2) the application of IMSI instead of in vitro fertilization in cases of unexplained infertility; (3) the age of the woman; and (4) the technical aspects. We have to be aware that this technique is demanding and has to be performed in the best working conditions so as not to impair the oocyte quality. The introduction of IMSI has the advantage that embryologists realize that more attention has to be paid during sperm selection even in case of classical intracytoplasmic sperm injection (ICSI). The application of IMSI leads to more and better quality blastocysts and, as consequence, it increases the chances of selecting the proper embryo for transfer with high implantation potential. Even though there is no real proof in the human species on the abnormal outcome generated by spermatozoa carrying vacuoles, a higher and better-resolution technique has to be added as an additional tool for ICSI knowing the possible consequence of sperm DNA damage for offsprings.


Archive | 2011

Cryopréservation d’ovocytes et d’embryons par congélation ou vitrification dans le cadre de l’assistance médicale à la procréation

Pierre Vanderzwalmen; Fabien Ectors; Y Papras; Matthias Zech; D. Jareno; Bernard Lejeune; Sandrine Vanderzwalmen; Barbara Wirleitner; Nicolas H. Zech; Luc Grobet

La cryopreservation est un procede permettant de garder les fonctions cellulaires ou tissulaires intactes en reduisant la temperature en dessous de celle a laquelle se deroulent normalement les reactions biochimiques.


Non-Invasive Sperm Selection for In Vitro Fertilization | 2015

Sperm Vacuoles: Origin and Implications

Pierre Vanderzwalmen; Nicolas H. Zech; Bernard Lejeune; Anton Neyer; S. Perrier d’Hauterive; Françoise Puissant; Astrid Stecher; Sabine Vanderzwalmen; Barbara Wirleitner; Olivier Gaspard

Not before the introduction of the Nomarski differential interference contrast optics (DIC), we became aware of the presence of so-called vacuoles on the surface of the sperm head. Before the implementation of motile-sperm organelle-morphology examination (MSOME), no manuscript at all mentioned that spermatozoa free of vacuole-like structures should be selected for injection.


Andrologie | 2008

Anonymat et compensation financière du don de gamètes et d’embryons en Belgique

Bernard Lejeune

ResumeUne législation, relative à la pratique de la procréation médicalement assistée (PMA) et à la destination des gamètes et des embryons surnuméraires, a été adoptée en 2007 et est entrée en vigueur fin juillet 2007 en Belgique.Elle ne change que peu de choses à la pratique courante sauf qu’elle limite drastiquement le nombre de bébés que l’on peut engendrer par donneur de gamètes. En Belgique, le don de sperme est en principe anonyme mais ne l’est pas obligatoirement: dans le cas où donneur et receveuse se présentent ensemble, font la demande d’un don direct et signent l’autorisation de procéder de la sorte, la procédure est recevable.Le don de sperme estgratuit mais il est autorisé d’accorder un dédommagement raisonnable au donneur pour les frais engagés et la perte de revenu éventuelle. Le don d’ovocytes est en principe anonyme et gratuit également mais il n’est pas interdit de procéder à un don dirigé (non anonyme) si l’ensemble des parties en signent l’autorisation. Dans ce cas, donneuse et receveuse se présentent ensemble.Il est également autorisé d’accorder undédommagement à la donneuse mais il n’y a pas d’accord jusqu’à présent sur le montant acceptable. En tenant compte des nécessités du traitement, il serait juste de prévoir une incapacité de travail de 10 à 15 jours, donc une perte de revenu équivalente que l’on devrait compenser par un dédommagement de 500 à 1000 euros, des déplacements, voire un séjour au voisinage du Centre de PMA pendant cette période pouvant également se chiffrer à 500 euros à 1000 euros. Le dédommagement justifié se monterait donc à 1000, voire 2000 euros. Ce montant semblait excessif jusqu’à présent mais les sensibilités pourraient changer. Il n’en reste pas moins vrai que les donneuses volontaires spontanées pour un don gracieux et anonyme sont rares.Certains centres procèdent à une permutation des donneuses pour assurer l’anonymat. Le don d’embryons est anonyme. Les embryons ne peuvent être commercialisés mais le Centre de PMA doit assurer la sécurité sanitaire de ces embryons et leur gestion au bout des 5 années légales de conservation. Ce qui a aussi un coût.AbstractBelgian law concerning medically assisted procreation (MAP) and use of gametes and supernumerary embryos was adopted in 2007 and entered into force at the end of July 2007. It has only a limited impact on routine clinical practice, but dramatically limits the number of pregnancies that can be achieved by gamete donation.In Belgium, sperm donation is theoretically anonymous, but anonymity is not mandatory: when the donor and recipient attend the clinic together, request direct donation and sign an agreement, this procedure is acceptable. Sperm donation is free but it is permitted to provide reasonable compensation to the donor for any expenses and loss of income.Ooocyte donation is also free and theoretically anonymous, but directed (non-anonymous) donation is not prohibited when all parties sign an agreement. In this case, the donor and recipient attend the clinic together.It is also permitted to provide compensation to the donor, but no agreement has been reached concerning the acceptable amount. By taking into account the need for treatment, it would be reasonable to provide for 10 to 15 days off work and therefore an equivalent loss of income that could be compensated by 500 to 1000 euros, travel expenses, or even accommodation close to the MAP clinic during this period, which could also represent 500 to 1000 euros. Justified compensation would therefore represent 1000 or even 2000 euros. This amount appeared to be excessive up until now, but opinions tend to change. It is nevertheless true that spontaneous volunteer donors for free and anonymous oocyte donation are rare.Some centres perform donor randomisation to ensure anonymity.Embryo donation is anonymous. Embryos cannot be sold, but the MAP clinic must ensure the health security of these embryos and their management after the 5-year legal storage period, which also has a certain cost.


Human Reproduction | 1997

Intracytoplasmic injection of spermatids retrieved from testicular tissue: influence of testicular pathology, type of selected spermatids and oocyte activation.

Pierre Vanderzwalmen; H. Zech; A Birkenfeld; M Yemini; G. Bertin; Bernard Lejeune; M. Nijs; L. Segal; A. Stecher; B. Vandamme; E. van Roosendaal; R. Schoysman


Human Reproduction | 1996

Fertilizing ability of immotile spermatozoa after intracytoplasmic sperm injection

M. Nijs; Pierre Vanderzwalmen; B. Vandamme; G. Segal-Bertin; Bernard Lejeune; L. Segal; E. van Roosendaal; R. Schoysman


Human Reproduction | 1998

The problems of spermatid microinjection in the human: the need for an accurate morphological approach and selective methods for viable and normal cells.

Pierre Vanderzwalmen; M. Nijs; R. Schoysman; G. Bertin; Bernard Lejeune; B. Vandamme; S Kahraman; H. Zech


Andrologie | 1996

La procréation médicalement assistée avec spermatozoïdes immatures: Impératifs cliniques et techniques chirurgicales

R. Schoysman; Bernard Lejeune; E. Van Roosendaal; L. Segal; Pierre Vanderzwalmen; M. Nijs; B. Vandamme; G. Bertin


Archive | 2014

Morphological Selection of Gametes and Embryos: Sperm

Pierre Vanderzwalmen; Magnus Bach; Olivier Gaspard; Bernard Lejeune; Anton Neyer; Françoise Puissant; Maximilian Schuff; Astrid Stecher; Sabine Vanderzwalmen; Barbara Wirleitner; Nicolas H. Zech


Human Reproduction | 1997

O-008. Reduced implantation rate after the transfer of frozen-thawed embryos obtained by ICSI

Bernard Lejeune; Pierre Vanderzwalmen; B. Vandamme; M. Nijs; G. Berlin; L. Segal; E. Vanroosendaal; R. Schoysman

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R. Schoysman

Free University of Brussels

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