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Featured researches published by Yvon Englert.


Oncologist | 2007

Fertility Preservation: Successful Transplantation of Cryopreserved Ovarian Tissue in a Young Patient Previously Treated for Hodgkin's Disease

Isabelle Demeestere; Philippe Simon; Serena Emiliani; Anne Delbaere; Yvon Englert

Cryopreservation of ovarian tissue is now offered as an experimental procedure to preserve the fertility of young patients with a high risk for premature ovarian failure resulting from cancer therapy. This is the only available option to preserve the fertility of prepubertal patients treated with gonadotoxic chemotherapy. At present, thousands of patients all over the world have undergone this procedure with the hope of later restoring their fertility. Although the efficiency of the transplantation of cryopreserved ovarian tissue to restore ovarian function has been established, reports of pregnancy are still very scarce. Here, we describe the second published full-term spontaneous pregnancy after an orthotopic and heterotopic transplantation of cryopreserved ovarian tissue in a 31-year-old woman previously treated by conditioning therapy for bone marrow transplantation for Hodgkins disease. This birth gives compelling evidence for the graft origin of the gamete and confirms the efficacy of ovarian tissue transplantation in restoring human natural fertility after oncological treatment. This case report stresses the importance of proposing the ovarian tissue cryopreservation procedure to all young patients who require potentially sterilizing treatment, with all alternative options to preserve fertility being duly taken into consideration.


AIDS | 2007

Safety and efficacy of sperm washing in HIV-1-serodiscordant couples where the male is infected: results from the European CREAThE network.

Lital Hollander; Mathieu Coudert; Carole Gilling-Smith; Alexandra Vucetich; Juliette Guibert; Pietro Vernazza; Jeanine Ohl; Michael Weigel; Yvon Englert; Augusto E. Semprini

Objective:To examine the safety and effectiveness of assisted reproduction using sperm washing for HIV-1-serodiscordant couples wishing to procreate where the male partner is infected. Design and methods:A retrospective multicentre study at eight centres adhering on the European network CREAThE and involving 1036 serodiscordant couples wishing to procreate. Sperm washing was used to obtain motile spermatozoa for 3390 assisted reproduction cycles (2840 intrauterine inseminations, 107 in-vitro fertilizations, 394 intra-cytoplasmic sperm injections and 49 frozen embryo transfers). An HIV test was performed in female partners at least 6 months after assisted reproduction attempt. The outcome measures recorded were number of assisted reproduction cycles, pregnancy outcome and HIV test on women post-treatment. Results:A total of 580 pregnancies were obtained from 3315 cycles. Pregnancy outcome was unknown in 47 cases. The 533 pregnancies resulted in 410 deliveries and 463 live births. The result of female HIV testing after assisted reproduction was known in 967 out of 1036 woman (7.1% lost to follow-up). All tests recorded were negative. The calculated probability of contamination was equal to zero (95% confidence interval, 0–0.09%). Conclusion:This first multicentre retrospective study of assisted reproduction following sperm washing demonstrates the method to be effective and to significantly reduce HIV-1 transmission risk to the uninfected female partner. These results support the view that assisted reproduction with sperm washing could not be denied to serodiscordant couples in developed countries and, where possible, could perhaps be integrated into a global public health initiative against HIV in developing countries.


Human Reproduction Update | 2009

Orthotopic and heterotopic ovarian tissue transplantation

Isabelle Demeestere; Philippe Simon; Serena Emiliani; Anne Delbaere; Yvon Englert

BACKGROUND Transplantation of ovarian tissue is, at present, the only clinical option available to restore fertility using cryopreserved ovarian tissue. More than 30 transplantations of cryopreserved tissue have been reported, and six babies have been born, worldwide, following this procedure. Despite these encouraging results, it is essential to optimize the procedure by improving the follicular survival, confirming safety and developing alternatives. Here, we review the different factors affecting follicular survival and growth after grafting. METHODS Relevant studies were identified by searching Pubmed up to January 2009 with English language limitation. The following key words were used: (ovarian tissue or whole ovary) AND (transplantation) AND (cryopreservation or pregnancy). Using the literature and personal experience, we examined relevant data on the different exogenous and clinical factors affecting follicular development after grafting. RESULTS Clinical factors such as the patients age and the transplantation sites influenced the lifespan of the graft. A heterotopic transplantation site is not optimal but offers some advantages and it may also promote the hormonal environment after a combined heterotopic and orthotopic transplantation. Exogenous factors such as antioxidants, growth factors or hormones were tested to improve follicular survival; however, their efficiency regarding further follicular development and fertility potential remains to be established. CONCLUSION Additional evidence is required to define optimal conditions for ovarian tissue transplantation. Alternatives such as whole ovary or isolated follicles transplantations require further investigation but are likely to be successful in humans in the future.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1998

Short-term medical complications of 1500 oocyte retrievals for in vitro fertilization and embryo transfer

Isabelle Govaerts; Fabienne Devreker; Anne Delbaere; Philippe Revelard; Yvon Englert

OBJECTIVE To evaluate the different short-term complications after in vitro fertilization and embryo transfer. DESIGN a retrospective study on 7 years in the fertility clinic of an university hospital. MATERIALS AND METHODS Short-term medical complications were analysed after 1500 transvaginal ultrasonographically guided oocyte retrievals. RESULTS Ovarian hyperstimulation syndrome (1.8%), pelvic infections (0.4%), intraperitoneal bleeding (0.2%) and adnexal torsions (0.13%) were observed. One case of adnexal torsion occurred during pregnancy (0.18%). Two unusual case of bowel endometriosis were encountered (0.13%). CONCLUSIONS Short-term medical complications after in vitro fertilization and embryo transfer are rare (2.8%). This contrast with the high rate of multifetal pregnancies which increases maternal and perinatal morbidity and mortality and must be considered as the major complication of in vitro fertilization treatment.


Biology of Reproduction | 2004

Effect of Insulin-Like Growth Factor-I During Preantral Follicular Culture on Steroidogenesis, In Vitro Oocyte Maturation, and Embryo Development in Mice

Isabelle Demeestere; C. Gervy; Julie Centner; Fabienne Devreker; Yvon Englert; Anne Delbaere

Abstract Insulin-like growth factor-I (IGF-I) is involved in the regulation of ovarian follicular development and has been shown to potentiate the FSH responsiveness of granulosa cells from preantral follicles. The aim of the present study was to investigate the effect of IGF-I during preantral follicular culture on steroidogenesis, subsequent oocyte maturation, fertilization, and embryo development in mice. Preantral follicles were isolated mechanically and cultured for 12 days in a simplified culture medium supplemented with 1% fetal calf serum, recombinant human FSH, transferrin, and selenium. In these conditions, follicles were able to grow and produce oocytes that could be matured and fertilized. The first experiment analyzed the effect of different concentrations of IGF-I (0, 10, 50, or 100 ng/ml) added to the culture medium on the follicular survival, steroidogenesis, and the oocyte maturation process. The presence of IGF-I during follicular growth increased the secretion of estradiol but had no effect on the subsequent oocyte survival and maturation rates. In the second experiment, IGF-I (0 or 50 ng/ml) was added to the culture medium during follicular growth, oocyte maturation, or both, and subsequent oocyte fertilization and embryo development rates were evaluated. Oocyte fertilization rates were comparable in the presence or absence of IGF-I. However, the blastocyst development rate was enhanced after follicular culture in the presence of IGF-I. Moreover, the total cell number of the blastocysts observed after differential labeling staining was also higher when follicles were cultured or matured in the presence of IGF-I.


Journal of Clinical Oncology | 2013

Gonadotropin-Releasing Hormone Agonist for the Prevention of Chemotherapy-Induced Ovarian Failure in Patients With Lymphoma: 1-Year Follow-Up of a Prospective Randomized Trial

Isabelle Demeestere; Pauline Brice; Fedro Peccatori; Alain Kentos; Isabelle Gaillard; Pierre Zachée; Rene-Olivier Casasnovas; Eric Van Den Neste; Julie Dechene; Vivianne De Maertelaer; Dominique Bron; Yvon Englert

PURPOSE To assess the efficacy of gonadotropin-releasing hormone agonist (GnRHa) in preventing chemotherapy-induced ovarian failure in patients treated for Hodgkin or non-Hodgkin lymphoma within the setting of a multicenter, randomized, prospective trial. PATIENTS AND METHODS Patients age 18 to 45 years were randomly assigned to receive either the GnRHa triptorelin plus norethisterone (GnRHa group) or norethisterone alone (control group) concomitantly with alkylating agents containing chemotherapy. The primary end point was the premature ovarian failure (POF) rate (follicle-stimulating hormone [FSH] ≥ 40 IU/L) after 1 year of follow-up. RESULTS Eighty-four of 129 randomly assigned patients completed the 1-year follow-up. The mean FSH values were higher in the control group than in the GnRHa group during chemotherapy; however, this difference was no longer observed after 6 months of follow-up. After 1 year, 20% and 19% of patients in the GnRHa and control groups, respectively, exhibited POF (P = 1.00). More than half of patients in each group completely restored their ovarian function (FSH < 10 IU/L), but the anti-Müllerian hormone values were higher in the GnRHa group than in the control group (1.4 ± 0.35 v 0.5 ± 0.15 ng/mL, respectively; P = .040). The occurrence of adverse events was similar in both groups with the exception of metrorrhagia, which was more frequently observed in the control group than the GnRHa group (38.4% v 15.6%, respectively; P = .024). CONCLUSION Approximately 20% of patients in both groups exhibited POF after 1 year of follow-up. Triptorelin was not associated with a significant decreased risk of POF in young patients treated for lymphoma but may provide protection of the ovarian reserve.


Journal of Assisted Reproduction and Genetics | 1986

Clinical Study on Embryo Transfer After Human in Vitro Fertilization

Yvon Englert; Françoise Puissant; Michel Camus; J. Van Hoeck; Fernand Leroy

One hundred forty-six embryo transfers were carried out in the In Vitro Fertilization (IVF) Clinic at St. Pierre Hospital, Brussels, between November 1983 and February 1985. In each of these cases a series of characteristics of the replacement procedure was systematically rates indicated that (i) no significant differences appeared among three different operators, (ii) the absence or occurrence of cervical bleeding and subjective evaluation of the procedure were related to the chances of establishing a pregnancy, and (iii) the duration of replacement had no influence on the outcome of trials. A prospeative randomized study of 100 replacements showed that (i) no better pregnancy rate was obtained by placing patients in the knee-to-chest rather than the dorsal position and (ii) the addition of a rigid external sleeve to the catheter did not provide any advantage. A simplified method of replacement is thus advocated.


Human Reproduction | 2014

Safety and usefulness of cryopreservation of ovarian tissue to preserve fertility: a 12-year retrospective analysis

Romain Imbert; Federica Moffa; Sophie Tsepelidis; Philippe Simon; Anne Delbaere; Fabienne Devreker; Julie Dechene; Alina Ferster; Isabelle Veys; Maxime Fastrez; Yvon Englert; Isabelle Demeestere

STUDY QUESTION Do the benefits of ovarian tissue cryopreservation outweigh the risks for patients seeking to preserve fertility before gonadotoxic treatment in various indications? SUMMARY ANSWER In >90% of the patients undergoing cryopreservation of ovarian tissue, oncological treatment was associated with a reduced ovarian reserve and in 30% of patients, premature ovarian failure (POF) occurred within 5 years. WHAT IS KNOWN ALREADY Ovarian tissue cryopreservation is an effective fertility preservation option, especially for pre-pubertal patients and patients who have a short time between diagnosis of a disease and gonadotoxic treatment. STUDY DESIGN, SETTING, DURATION This study retrospectively analysed ovarian function and fertility recovery rates, as well as ovarian tissue characteristics, of patients who underwent ovarian tissue cryopreservation at Erasme Hospital between 1999 and 2011. PARTICIPANTS/MATERIALS, SETTINGS, METHODS A total of 225 patients referred from 15 Belgian oncological units underwent cryopreservation of ovarian tissue before gonadotoxic therapy for malignant or benign diseases. There were 28 patients (12.4%) who died during follow-up due to recurrence of disease. One severe adverse event occurred during anaesthesia for ovarian tissue collection, leading to the death of the patient. Ovarian function and fertility outcomes were available for 114 patients including 13 girls who were pre-pubertal at the time of the procedure. Eight patients had undergone ovarian tissue transplantation in order to restore their fertility after remission of the disease. MAIN RESULTS AND THE ROLE OF CHANCE Breast cancer and haematological disease were the most frequent indications for ovarian tissue cryopreservation. Overall, 90% of post-pubertal patients were diagnosed with poor ovarian reserve (AMH < 0.5 ng/ml) after a mean of 50 months of follow-up (11-125 months), including 30% with POF (FSH > 40 IU/ml). Breast cancer patients had a lower rate of POF than did post-pubertal patients with haematological diseases (11 versus 34.5%, respectively), despite the older age (mean 31 versus 23.5 years old, respectively) of the breast cancer patients. Ovarian function returned in 71 post-pubertal patients without the need for grafts of cryopreserved tissue. Spontaneous pregnancies were reported for 33 of them, leading to 34 live births. Among the 13 pre-pubertal patients who reached pubertal age during the follow-up, 10 had POF. Eight patients received cryopreserved ovarian grafts to reverse POF and three of them have already become pregnant. LIMITATIONS, REASONS FOR CAUTION This study is a retrospective analysis. The cohort was not compared with a control group of patients who did not undergo the procedure. WIDER IMPLICATIONS OF THE FINDINGS After careful evaluation of the surgical risks, ovarian tissue cryopreservation can be proposed as an efficient option to preserve the fertility of children and young adults facing gonadotoxic therapies. However, alternative procedures such as oocyte or embryo cryopreservation should be considered as first options especially for older patients or if there is high risk of neoplastic cells within the ovaries. STUDY FUNDING/COMPETING INTEREST This study was supported by the Télévie, FNRS-FRSM and Fondation Belge contre le cancer. There are no competing interests to report.


Reproductive Biology and Endocrinology | 2011

Vitrification of in vitro matured oocytes collected from antral follicles at the time of ovarian tissue cryopreservation

Giovanna Fasano; Federica Moffa; Julie Dechene; Yvon Englert; Isabelle Demeestere

BackgroundIn the past few years, cryopreservation of ovarian tissue has become an established procedure proposed in many centers around the world and transplantation has successfully resulted in full-term pregnancies and deliveries in human. This prospective study aims to evaluate the feasibility of vitrifying in vitro matured oocytes (IVM) isolated at the time of ovarian tissue cryopreservation to improve the efficiency of fertility preservation programs.MethodsOocyte-cumulus complexes were retrieved from freshly collected ovarian cortex by aspirating antral follicular fluid, and were matured in vitro for 24-48 h prior to vitrification. Oocytes were matured in an IVM commercial medium (Copper Surgical, USA) supplemented with 75 mIU/ml FSH and 75 mIU/ml LH and vitrified using a commercial vitrification kit (Irvine Scientific, California) in high security vitrification straws (CryoBioSystem, France). Oocyte collection and IVM rates were evaluated according to the age, the cycle period and the amount of tissue collected.ResultsImmature oocyte retrieval from ovarian tissue was carried out in 57 patients between 8 and 35 years of age, undergoing ovarian tissue cryopreservation. A total of 266 oocytes were isolated, 28 of them were degenerated, 200 were at germinal vesicle stage (GV), 35 were in metaphase I (MI) and 3 displayed a visible polar body (MII). The number of oocytes collected was positively correlated with the amount of tissue cryopreserved (p < 0.001) and negatively correlated with the age of the patients (p = 0.005). Oocytes were obtained regardless of menstrual cycle period or contraception. A total maturation rate of 31% was achieved, leading to the vitrification of at least one mature oocyte for half of the cohort.ConclusionsThe study showed that a significant number of immature oocytes can be collected from excised ovarian tissue whatever the menstrual cycle phases and the age of the patients, even for prepubertal girls.


Human Reproduction | 2010

Birth of a second healthy girl more than 3 years after cryopreserved ovarian graft

Isabelle Demeestere; Philippe Simon; Federica Moffa; Anne Delbaere; Yvon Englert

Passos EP. Prolactin and growth hormone secretion alter thyrotrophin-releasing hormona infusion and dopaminergic (DA2) blockade in infertile patients with minimal/mild endometriosis. Hum Reprod 2002;17:960–965. Gomez R, Gonzalez-Izquierdo M, Zimmermann RC, Novella-Maestre E, Alonso-Muriel I, Sanchez-Criado J, Remohi J, Simon C, Pellicer A. Low dose dopamine agonist administration blocks VEGF mediated vascular permeability without altering VEGFR-2 dependent luteal angiogenesis in a rat ovarian hyperstimulation model. Endocrinology 2006;147:5400–5411. GregoriouG,Bakas P,VitoratosN, PapadiasK,GoumasK,ChryssicopoulosA, Creatsas G. Evaluation of serum prolactin levels in patients with endometriosis and infertility. Gynecol Obstet Invest 1999;48:48–51. Laschke MW, Menger MD. In vitro and in vivo approaches to study angiogenesis in the pathophysiology and therapy of endometriosis. Hum Reprod Update 2007;13:331–342. Maas JW, Groothuis PG, Dunselman GA, d Goeij AF, Struijker-Boudier HA, Evers JL. Endometrial angiogenesis throughout the humanmenstrual cycle. Hum Reprod 2001;16:1557–1561. Nisolle M, Casanas-Roux F, Anaf V, Mine JM, Donnez J. Morphometric study of the stromal vascularization in peritoneal endometriosis. Fertil Steril 1993;59:681–684. Novella-Maestre E, Carda C, Noguera I, Ruiz-Sauri A, Garcia-Velasco JA, Simon C, Pellicer A. Dopamine agonist administration causes a reduction in endometrial implants through modulation of angiogenesis in experimentally induced endometriosis. Hum Reprod 2009; 24:1025–1035. Ricci E, Parazzini F,MottaT, FerrariCI,ColaoA,ClavennaA,Rocchi F,Gangi E, Paracchi S, Gasperi M et al. Pregnancy outcome after cabergoline treatment in early weeks of gestation. Reprod Toxicol 2002;16:791–793. Robert E, Musatti L, Piscitelli G, Ferrari CI. Pregnancy outcome after treatment with the ergot derivative, cabergoline. Reprod Toxicol 1996; 10:333–337. Vercellini P, Crosignani PP, Somigliana E, Berlanda N, Barbara G, Fedele L. Medical treatment for rectovaginal endometriosis: what is the evidence? Hum Reprod 2009;24:2504–2514.

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Anne Delbaere

Université libre de Bruxelles

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Serena Emiliani

Free University of Brussels

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Fabienne Devreker

Université libre de Bruxelles

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Isabelle Demeestere

Université libre de Bruxelles

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Jamila Biramane

Free University of Brussels

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Corinne Liesnard

Université libre de Bruxelles

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Isabelle Place

Université libre de Bruxelles

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Anne-Sophie Vannin

Université libre de Bruxelles

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