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Dive into the research topics where A. Van Steirteghem is active.

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Featured researches published by A. Van Steirteghem.


The Lancet | 1992

Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte

G. Palermo; H. Joris; Paul Devroey; A. Van Steirteghem

Intracytoplasmic sperm injection (ICSI) is a promising assisted-fertilisation technique that may benefit women who have not become pregnant by in-vitro fertilisation (IVF) or subzonal insemination (SUZI) of oocytes. We have used ICSI to treat couples with infertility because of severely impaired sperm characteristics, and in whom IVF and SUZI had failed. Direct injection of a single spermatozoon into the ooplasm was done in 47 metaphase-II oocytes: 38 oocytes remained intact after injection, 31 became fertilised, and 15 embryos were replaced in utero. Four pregnancies occurred after eight treatment cycles--two singleton and one twin pregnancy, and a preclinical abortion. Two healthy boys have been delivered from the singleton pregnancies and a healthy boy and girl from the twin pregnancy.


Human Reproduction | 1995

Pregnancies after testicular sperm extraction and intracytoplasmic sperm injection in non-obstructive azoospermia

Paul Devroey; J. Liu; Z.P. Nagy; Anita Goossens; Herman Tournaye; M. Camus; A. Van Steirteghem; Sherman J. Silber

In this study (May 1 until August 31, 1994) a total of 15 azoospermic patients suffering from testicular failure were treated with a combination of testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). Spermatozoa were available for ICSI in 13 of the patients. Out of 182 metaphase II injected oocytes, two-pronuclear fertilization was observed in 87 (47.80%); 57 embryos (65.51%) were obtained for either transfer or cryopreservation. Three ongoing pregnancies out of 12 replacements (25%) were established, including one singleton, one twin and one triplet gestation. The ongoing implantation rate was 18% (six fetal hearts out of 32 embryos replaced).


Human Reproduction | 2008

Consensus on infertility treatment related to polycystic ovary syndrome

Basil C. Tarlatzis; Bart C.J.M. Fauser; Richard S. Legro; Robert J. Norman; Kathleen M. Hoeger; Renato Pasquali; Stephen Franks; I. E. Messinis; R. F. Casper; Roy Homburg; Rogerio A. Lobo; R. W. Rebar; R. Fleming; Bruce R. Carr; Ph. Bouchard; J. Chang; J. N. Hugues; R. Azziz; Efstratios M. Kolibianakis; G. Griesinger; K. Diedrich; Adam Balen; C. Farquhar; Paul Devroey; P. C. Ho; J. Collins; Dimitrios G. Goulis; R. Eijkemans; Pier Giorgio Crosignani; Alan H. DeCherney

The treatment of infertile women with polycystic ovary syndrome (PCOS) is surrounded by many controversies. This paper describes, on the basis of the currently available evidence, the consensus reached by a group of experts regarding the therapeutic challenges raised in these women. Before any intervention is initiated, preconceptional counselling should be provided emphasizing the importance of life style, especially weight reduction and exercise in overweight women, smoking and alcohol consumption. The recommended first-line treatment for ovulation induction remains the anti-estrogen clomiphene citrate (CC). Recommended second-line intervention, should CC fail to result in pregnancy, is either exogenous gonadotrophins or laparoscopic ovarian surgery (LOS). The use of exogenous gonadotrophins is associated with increased chances for multiple pregnancy and, therefore, intense monitoring of ovarian response is required. LOS alone is usually effective in <50% of women and additional ovulation induction medication is required under those circumstances. Overall, ovulation induction (representing the CC, gonadotrophin paradigm) is reported to be highly effective with a cumulative singleton live birth rate of 72%. Recommended third-line treatment is in vitro fertilization. More patient-tailored approaches should be developed for ovulation induction based on initial screening characteristics of women with PCOS. Such approaches may result in deviation from the above mentioned first-, second- or third-line ovulation strategies in well-defined subsets of patients. Metformin use in PCOS should be restricted to women with glucose intolerance. Based on recent data available in the literature, the routine use of this drug in ovulation induction is not recommended. Insufficient evidence is currently available to recommend the clinical use of aromatase inhibitors for routine ovulation induction. Even singleton pregnancies in PCOS are associated with increased health risk for both the mother and the fetus.


Prenatal Diagnosis | 1998

Preimplantation diagnosis for Huntington's disease (HD): clinical application and analysis of the HD expansion in affected embryos

Karen Sermon; V. Goossens; Sara Seneca; W. Lissens; A. De Vos; M. Vandervorst; A. Van Steirteghem; I. Liebaers

Huntingtons disease (HD) is an autosomal dominant disease characterized by motor disturbance, cognitive loss and psychiatric manifestations, starting between the fourth and the fifth decade, followed by death within 10–20 years of onset of the disease. The disease‐causing mutation is an expansion of a CAG triplet repeat at the 5′ coding end of the Huntington gene. We have developed a single‐cell PCR assay for the HD gene in order to propose preimplantation genetic diagnosis (PGD) for the couples at risk. We present here our first results with our first nine PGD cycles and also discuss the behaviour of the disease‐causing expansion in pre‐implantation embryos. Copyright


Cells Tissues Organs | 2000

Zona Hardening, Zona Drilling and Assisted Hatching: New Achievements in Assisted Reproduction

A. De Vos; A. Van Steirteghem

Prior to fertilization, the zona pellucida surrounding the mammalian oocyte acts as a species-specific sperm barrier and is involved in sperm binding. After fertilization, the zona plays a role in blocking polyspermic fertilization, it protects the integrity of the preimplantation embryo during early embryonic development, and also helps its oviductal transport. Zona hardening occurs naturally after fertilization in order to ensure this threefold function. A combination of lysins produced by the cleaving embryo or the uterus and physical expansion then reduces the zona thickness in preparation for hatching. Zona hardening, although not readily quantifiable, may also be induced by in vitro culture and by in vivo aging. Indeed, prolonged exposure of human oocytes and embryos to artificial culture conditions seems to impair their ability to implant. Implantation rates are also inversely correlated with advanced female age. Recently, failure of the embryonic zona pellucida to rupture following blastocyst expansion has been put forward as a possible contributing factor in implantation failure. In order to help embryos escape from their zonae during blastocyst expansion, different types of assisted hatching have been developed. Zona drilling involves the creation of an opening in the zona with acidified medium, whereas zona slitting is carried out in the same manner as partial zona dissection. In zona thinning, the zona is just made thinner over a certain area without a hole or a slit being created. More recently, laser-assisted hatching has been introduced. In vitro studies with both mouse and human embryos have indicated that an artificial gap in the zona pellucida significantly improves the hatching ability of blastocysts grown in vitro as compared to non-micromanipulated embryos. However, the clinical relevance of assisted hatching within an assisted reproduction program remains controversial and elusive. Very few randomized studies are available. Most reports are of retrospective analyses which report either no differences in implantation and pregnancy rates between assisted hatching and control embryos or better results after assisted hatching. Five randomized controlled studies suggest that assisted hatching - of no benefit to the overall patient population - might be of value in increasing embryo implantation rates only in selected cases. No further evidence exists for an age-related benefit from assisted hatching in patients with advanced maternal age.Prior to fertilization, the zona pellucida surrounding the mammalian oocyte acts as a species-specific sperm barrier and is involved in sperm binding. After fertilization, the zona plays a role in blo


Journal of Assisted Reproduction and Genetics | 1989

An 18-month survey of infertility treatment by in vitro fertilization, gamete and zygote intrafallopian transfer, and replacement of frozen-thawed embryos

Catherine Staessen; Michel Camus; I. Khan; Johan Smitz; L. Van Waesberghe; A. Wisanto; Paul Devroey; A. Van Steirteghem

An 18-month survey of infertility treatment by in vitro fertilization (IVF) and related procedures at the Centre for Reproductive Medicine of the Vrije Universiteit Brussel is described. During this period, 1326 treatment cycles were started in patients with long-standing infertility and 1135 oocyte retrievals were performed in 771 different patients. IVF and embryo transfer (ET) after laparoscopic (N=793) or ultrasonically guided (N=342) ovum pickup, gamete intrafallopian transfer (GIFT;N=284), or zygote intrafallopian transfer (ZIFT;N=15) combined with IVF as well as the replacement of cryopreserved embryos yielded an overall pregnancy rate of 21.8% per started cycle. Echographic and laparoscopic oocyte retrieval gave similar results except for a higher fertilization rate after echographic-guided retrieval. For in vitro fertilization and embryo transfer an overall pregnancy rate of 26% per transfer was obtained. For GIFT and ZIFT the pregnancy rates were, respectively, 27.8 and 46.7% per replacement. For each procedure onethird of the pregnancies aborted. After the replacement of frozen and thawed embryos, during a natural cycle, a significantly lower fetal loss was observed.


Reproductive Biomedicine Online | 2006

NEW BELGIAN EMBRYO TRANSFER POLICY LEADS TO SHARP DECREASE IN MULTIPLE PREGNANCY RATE

L. Van Landuyt; Greta Verheyen; Herman Tournaye; Michel Camus; Paul Devroey; A. Van Steirteghem

Since 1 July 2003, a new transfer policy aiming to reduce multiple pregnancies was brought into law in Belgium. The policy restricts the number of embryos transferred, depending on the patients age and treatment cycle. This study aimed to evaluate the effect of this policy. Two 15-month periods before and after the start of the new law were compared for the following parameters: positive human chorionic gonadotrophin (HCG), clinical pregnancy rate and multiple pregnancy rate according to the age categories defined by the policy: <36, 36-39 and 40-42 years. HCG rates (34.2 and 32.8%) and clinical pregnancy rates (26.2 and 24.0%) per cycle were similar for the two periods. Overall, the multiple pregnancy rate was reduced from 29.1 to 9.5% (all patients) and from 28.9 to 6.2% in women <36 years. Most twins were observed in the third cycle of patients <36 years and in the first three cycles in women of 36-39 years. It can be concluded that a significant decline (P < 0.001) in multiple pregnancies was mainly observed in patients <36 years of age. Clinical pregnancy rates were not compromised by the new law. Elective single embryo transfer should be considered more seriously for women 36-39 years of age.


Reproductive Biomedicine Online | 2003

Clomiphene citrate versus letrozole for ovarian stimulation: A pilot study

H. Mousavi Fatemi; Efstratios M. Kolibianakis; Herman Tournaye; M. Camus; A. Van Steirteghem; Paul Devroey

The purpose of this pilot study was to compare the endocrinological environment of cycles stimulated with clomiphene citrate (CC) or letrozole. Fifteen patients undergoing intrauterine insemination (IUI) received from day 3 to day 7 of the cycle either letrozole 2.5 mg/day (n = 7) or clomiphene citrate 100 mg/day (n = 8). IUI was performed one day after the detection of LH peak. No luteal support was administered. Significantly lower serum oestradiol concentrations were present in the follicular phase on days 9, 13 and 15 of the cycle and in the luteal phase on days 3 and 6 post-IUI in the letrozole group compared with those in the CC group. Progesterone concentrations and oestradiol concentrations were significantly lower in the letrozole group than in the CC group on the day of LH peak. Significantly more follicles developed in patients in the CC group compared with those in the letrozole group. In conclusion, significantly lower oestradiol concentrations and fewer follicles are observed in cycles stimulated with 2.5 mg letrozole compared with cycles stimulated with 100 mg CC from day 3 to day 7 of the cycle.


Prenatal Diagnosis | 1997

Clinical application of preimplantation diagnosis for myotonic dystrophy

Karen Sermon; W. Lissens; H. Joris; Sara Seneca; S. Desmyttere; Paul Devroey; A. Van Steirteghem; I. Liebaers

Myotonic dystrophy (DM) or Steinerts disease is a progressive autosomal dominant disease characterized by increasing muscle weakness, myotonia, cataracts, and endocrine abnormalities such as diabetes and testicular atrophy. The gene for DM was cloned in 1992 and the mutation was shown to be an expanded trinucleotide (CTG) repeat. A polymerase chain reaction (PCR)‐based assay was described soon after that would allow (prenatal) diagnosis of the disease. Based on these PCR assays, we have developed a method for carrying out single‐cell PCR for DM. In preimplantation diagnosis, embryos obtained in vitro are checked for the presence or absence of a disease, after which only embryos shown to be free of the disease under consideration are returned to the mother. A single‐cell assay was developed for preimplantation diagnosis in couples where one of the parents is afflicted with DM. Twenty intracytoplasmic sperm injection (ICSI) cycles were carried out in eight patients and between one and four embryos were replaced in 17 out of 20 cycles. Two of the patients became pregnant and have had prenatal diagnosis which has confirmed that they are unaffected.


Human Reproduction Update | 2010

Europe the continent with the lowest fertility

D. T. Baird; John A. Collins; Johannes L.H. Evers; Henri Leridon; W. Lutz; E.R. te Velde; O. Thevenon; Pier Giorgio Crosignani; Paul Devroey; K. Diedrich; Bart C.J.M. Fauser; Lynn R. Fraser; Joep Geraedts; Luca Gianaroli; Anna Glasier; Arne Sunde; Basil C. Tarlatzis; A. Van Steirteghem; Anna Veiga

INTRODUCTION Although fertility rates are falling in many countries, Europe is the continent with the lowest total fertility rate (TFR). This review assesses trends in fertility rates, explores possible health and social factors and reviews the impact of health and social interventions designed to increase fertility rates. METHODS Searches were done in medical and social science databases for the most recent evidence on relevant subject headings such as TFR, contraception, migration, employment policy and family benefits. Priorities, omissions and disagreements were resolved by discussion. RESULTS The average TFR in Europe is down to 1.5 children per woman and the perceived ideal family size is also declining. This low fertility rate does not seem directly caused by contraception since in Northern and Western Europe the fertility decline started in the second half of the 1960s. Factors impacting on lower fertility include the instability of modern partnerships and value changes. Government support of assisted human reproduction is beneficial for families, but the effect on TFR is extremely small. Government policies that transfer cash to families for pregnancy and child support also have small effects on the TFR. CONCLUSIONS Societal support for families and for couples trying to conceive improves the lives of families but makes no substantial contribution to increased fertility rates.

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Paul Devroey

Vrije Universiteit Brussel

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I. Liebaers

Vrije Universiteit Brussel

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Herman Tournaye

Vrije Universiteit Brussel

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M. Camus

VU University Amsterdam

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Johan Smitz

Vrije Universiteit Brussel

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H. Joris

Vrije Universiteit Brussel

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Karen Sermon

Vrije Universiteit Brussel

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C. Staessen

VU University Amsterdam

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H. Van de Velde

Vrije Universiteit Brussel

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A. Wisanto

VU University Amsterdam

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