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E Van Assche

Publications and source records attributed to E Van Assche.

28 records · Page 2Linked to original sources
PubMed1996

Prospective follow-up study of 877 children born after intracytoplasmic sperm injection (ICSI), with ejaculated epididymal and testicular spermatozoa and after replacement of cryopreserved embryos obtained after ICSI.

A prospective follow-up study of 877 children born after ICSI was carried out. The aim of this study was to compile data on karyotypes, congenital malformations, growth parameters and developmental milestones so as to evaluate the safety of this new technique. The follow-up study included agreement to genetic counselling and prenatal diagnosis and was based on a physical examination at the Centre for Medical Genetics (Dutch-speaking Brussels Free University, Brussels, Belgium) at 2 months, 1 year and 2 years, when major and minor malformations and a psychomotor evolution were recorded. Between April 1991 and July 1995, 904 pregnancies obtained after intracytoplasmic sperm injection (ICSI) led to the birth of 877 children (465 singletons, 379 twins and 33 triplets). Prenatal diagnosis determined a total of 486 karyotypes, of which six were abnormal (1.2%) and six (1.2%) were familial structural aberrations, all transmitted from the father. This slight increase in de-novo chromosomal aberrations and the higher frequency of transmitted chromosomal aberrations are probably linked directly to the characteristics of the infertile men treated rather than to the ICSI procedure itself. In all, 23 (2.6%) major malformations were observed in the children born, defined as those causing functional impairment or requiring surgical correction. No particular malformation was disproportionately frequent. Compared with most registers of children born after assisted reproduction and with registers of malformation in the general population, the figure of 2.6% was within the expected range. These observations should be further completed by others and by collaborative efforts. In the meantime, patiens should be counselled about the available data before any treatment: the risk of transmitted chromosomal aberrations, the risk of de-novo, mainly sex chromosomal, aberrations and the risk of transmitting fertility problems to the offspring. Patients should also be reassured that there seems to be no higher incidence of congenital malformations in children born after ICSI.

Congenital Abnormalities↗
PubMed1996

Prospective follow-up study of 423 children born after intracytoplasmic sperm injection.

In order to evaluate the safety of the intracytoplasmic sperm injection (ICSI) procedure, a prospective follow-up study of 423 children born after ICSI was carried out. The aim of this study was to compile data on karyotypes, congenital malformations, growth parameters and developmental milestones. Before starting the infertility treatment, couples were asked to participate in a follow-up study including genetic counselling and prenatal diagnosis. The follow-up study of the child was based on a visit to the paediatrician-geneticist at birth or at 2 months of age, at 1 year and at 2 years of age when a physical examination for major and minor malformations and a psychomotoric evaluation were done. Between April 1991 and September 1994, 320 pregnancies obtained after ICSI led to the birth of 423 children (222 singletons, 186 twins and 15 triplets). Prenatal diagnosis determined a total of 293 karyotypes, one of which was abnormal (0.3%), and four were benign familial structural aberrations, all inherited from the paternal side. A total of 14 (3.3%) major malformations were observed, defined as those causing functional impairment or requiring surgical correlation. Neurological or developmental problems at the age of 2 months were found in 14 children, four of whom were multiples. Compared to most registers of children born after assisted reproduction and to registers of malformations in the general population, the figure of 3.3% major malformations is within the expected range. Before drawing any firm conclusion, further careful evaluations of the available data are necessary.

Adult↗
PubMed1996

Testicular sperm recovery in nine 47,XXY Klinefelter patients.

Klinefelter's syndrome is generally characterized by hypergonadotrophic hypogonadism and azoospermia. The clinical features, however, are variable, and occasionally severe oligozoospermia may be present. Usually in these cases a 46,XY/47,XXY mosaic karyotype is involved. However, focal spermatogenesis and severe oligozoospermia have been reported in 47,XXY individuals too. In the present study we investigated whether testicular spermatozoa can be recovered in 47,XXY patients with a view to intracytoplasmic sperm injection (ICSI). In four out of nine apparently non-mosaic 47,XXY patients, spermatozoa were recovered from the wet preparations of testicular tissue and ICSI was performed in three couples. In one patient in whom spermatozoa were successfully recovered and used for ICSI, no spermatozoa were retrieved at a second trial. Although these results show that in some 47,XXY individuals testicular spermatozoa can be successfully recovered and even used for ICSI, at present this approach should be considered experimental. There may indeed be some concern about the chromosomal normality of the embryos generated through this infertility treatment. Patients with Klinefelter's syndrome should therefore be counselled about the complexity of this treatment, which involves multiple testicular biopsies from hypogonadal testes, ICSI and preimplantation diagnosis by fluorescence-in-situ hybridization.

Adult↗
PubMed1996

Preimplantation diagnosis for X and Y normality in embryos from three Klinefelter patients.

In some 47,XXY Klinefelter patients without evidence of mosaicism, testicular spermatozoa can be successfully recovered and used for intracytoplasmic sperm injection (ICSI). To ensure the replacement of embryos with a normal X and Y chromosome pattern, preimplantation diagnosis can be performed. This paper reports on three 47,XXY Klinefelter patients from whom it was possible to retrieve testicular spermatozoa in order to perform ICSI. From their healthy wives a total of 27 oocyte-cumulus complexes were retrieved from which 22 metaphase-II oocytes were obtained and injected; 19 of these were intact after injection. Two distinct pronuclei were observed in eight oocytes (42.1%) 18 h after injection. On day 3 of development, five embryos (62.5%) had reached at least the 6-cell stage and were of sufficient quality to undergo biopsy and subsequent preimplantation diagnosis for sex chromosome analysis by fluorescent in-situ hybridization. The four embryos diagnosed as normal were transferred to three respective patients, resulting in one biochemical pregnancy. The remaining cells of the fifth embryo were analysed afterwards, revealing a normal X and Y chromosome constitution. So far, in the five embryos diagnosed, a normal sex chromosome pattern has been observed.

Embryo, Mammalian↗
PubMed1994

Assisted fertilization by subzonal insemination and intracytoplasmic sperm injection.

The results of 600 consecutive treatment cycles of subzonal insemination (SUZI) and intracytoplasmic sperm injection (ICSI) are described in couples with failed fertilization after standard IVF or insufficient spermatozoa in the ejaculate for IVF. More oocytes were damaged by ICSI (16.3%) than by SUZI (8.5%) and the normal fertilization rate was substantially higher after ICSI (49.1% v. 16.6%). Subsequent development of two-pronuclear oocytes in vitro was 80% after SUZI and 73.9% after ICSI. Significantly more triple embryo replacements were carried out after ICSI than after SUZI. Embryo transfers were possible in 421 of the 600 cycles. There were 63 pregnancies after ICSI (215 transfers) and 23 after SUZI (156 transfers); 10 additional pregnancies were achieved after 50 transfers of a mixture of SUZI and ICSI embryos. The results of fetal karyotypes and follow-up of the children do not indicate an increase in congenital malformations.

Adult↗
PubMed1994

Prospective follow-up study of 55 children born after subzonal insemination and intracytoplasmic sperm injection.

In 163 couples referred for assisted fertilization, pregnancy was established by subzonal insemination (SUZI), intracytoplasmic sperm injection (ICSI) or a combination of both techniques. These couples agreed to participate in a prospective study that included a prenatal diagnosis and clinical follow-up of the children. No cytogenetic aberrations were observed in 43 children tested. In 23 pregnancies occurring after SUZI, 15 women gave birth to 21 children. After replacement of combined SUZI and ICSI embryos, 10 pregnancies resulted in 8 deliveries with 10 children. Transfer of ICSI embryos led to 130 pregnancies ending in 20 deliveries with 24 children, with many others still ongoing successfully. In total, 55 children have been examined: 29 boys and 26 girls. One child from a singleton pregnancy presented multiple congenital malformations; one twin child presented a quadriparesis. In this observational study on a limited number of children, the incidence of major malformations was not different from the incidence in the general population.

Abnormalities, Multiple↗
PubMed1993

Higher success rate by intracytoplasmic sperm injection than by subzonal insemination. Report of a second series of 300 consecutive treatment cycles.

Subzonal insemination (SUZI) and intracytoplasmic sperm injection (ICSI) were carried out in 300 treatment cycles in couples unable to be helped by conventional in-vitro fertilization treatment. More oocytes were damaged by ICSI (13.5%) than by SUZI (7.1%). The normal fertilization rate was substantially higher after ICSI (51.0%) than after SUZI (14.3%) and was related to the semen characteristics. The cleavage rate was similar for both procedures (77%). After 217 embryo transfers (72.3% of the treatment cycles) 66 pregnancies were established, i.e. pregnancy rates of 22.0% per started cycle and 30.4% per embryo transfer. So far, pregnancy loss has occurred in 27.3% of the pregnancies, nine healthy children have been born after eight deliveries and 41 clinical pregnancies are progressing uneventfully. Chorionic villus sampling or amniocentesis have been performed in 35 pregnancies and 39 normal fetal karyotypes have been obtained after cytogenetic analysis.

Female↗
PubMedDate not supplied

The Brussels' experience of more than 5 years of clinical preimplantation genetic diagnosis.

This paper describes the 5 years' experience of preimplantation genetic diagnosis (PGD) at the Brussels Free University. Our first PGD was carried out in February 1993. Up to October 1998, we carried out 183 PGD cycles on fresh cleavage embryos of 92 couples for 25 different conditions. Patients were treated for autosomal recessive (n = 39), autosomal dominant (n = 65) and X-linked recessive (n = 47) monogenic disorders as well as for autosomal structural aberrations (n = 10), sex chromosome numerical and structural aberrations (n = 21) and a combination of the two latter (n = 1). Specific diagnosis was carried out by polymerase chain reaction (n = 108). Fluorescence in-situ hybridization was used for sexing (n = 64) and structural aberrations (n = 11). We transferred 1.6 +/- 1.1 embryos per cycle, resulting in an implantation rate of 12.0% per replaced embryo. Ongoing pregnancies were achieved in 29 cycles, i.e. 23 singletons, five twins and one dichorionic triplet with an acardius acranius. The ongoing pregnancy rates per cycle, per transfer and per couple were 16.4, 19.9 and 31.5% respectively. While 28 ongoing pregnancies resulted in the births of 34 infants, one pregnancy was terminated after misdiagnosis. The results of 24 PGD were confirmed by prenatal diagnosis or after birth while no information was available in four pregnancies. Our series demonstrates that PGD is a feasible technique by which to avoid the birth of genetically affected children to couples at risk.

Adult↗
PubMedDate not supplied

PGD in 47,XXY Klinefelter's syndrome patients.

The use of ICSI has been a major breakthrough in the treatment of male infertility. Even azoospermic patients with focal spermatogenesis in the testis, may benefit from the ICSI technique in order to father a child. As ICSI use has become more common, centres have introduced infertility treatment for Klinefelter patients. To date, 34 healthy children have been born using ICSI without PGD, and the conception of one 47,XXY fetus has been reported. In view of the possible risk of an increased gonosome number in the spermatozoa of Klinefelter patients, a safer approach--offering these couples ICSI combined with PGD--has been used, and has resulted in the birth of three healthy children. Couples in which the male suffered from Klinefelter's syndrome were first treated in 1995; these patients were offered ICSI + PGD using FISH technology, notably to enumerate the X and Y chromosomes. ICSI + PGD was performed in 32 cycles of 20 couples with spermatozoa originating from a fresh ejaculate (n = 1), testicular biopsy (n = 21) or frozen-thawed testicular biopsy (n = 10). Normal fertilization occurred in 56.0 +/- 22.4% of the successfully injected oocytes. On day 3 of development, 119 embryos from 29 cycles were of sufficient quality to undergo biopsy and subsequent PGD; a positive result was obtained in 113 embryos. Embryos were available for transfer in 26 cycles, with a mean of 1.6 +/- 0.6 embryos per transfer. Eight pregnancies were obtained, and five resulted in a delivery. A total of 113 embryos from couples with Klinefelter's syndrome was compared with 578 embryos from control couples with X-linked disease where PGD was used to determine gender. A significant fall occurred in the rate of normal embryos for couples with Klinefelter's syndrome (54.0%) compared with controls (77.2%). Moreover, a significantly increased risk of abnormalities was observed for sex chromosomes and autosomes; for each autosome separately, this reached significance level for chromosomes 18 and 21 only. Hence, a cautious approach is warranted in advising couples with non-mosaic Klinefelter's syndrome. Moreover, the use of ICSI + PGD or prenatal diagnosis should be carefully considered.

Embryonic and Fetal Development↗