Showing papers by "A. Van Steirteghem published in 2003"

PGD in 47,XXY Klinefelter’s syndrome patients

Abstract: 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.

Developmental outcome at 2 years of age for children born after ICSI compared with children born after IVF.

Abstract: Background Since the introduction of ICSI in 1991, medical outcome studies on ICSI children have been performed, but few have addressed developmental outcome. Hence, this outcome was assessed by performing a standard developmental test on children born after ICSI as compared with children born after IVF, at the age of 2 years. Methods In a prospective study, the medical and developmental outcome of 439 children born after ICSI (378 singletons, 61 twins) were compared with those of 207 children born after IVF (138 singletons, 69 twins), at the age of 24-28 months. These children were part of a cohort of children followed since birth. Of children reaching the age of 24-28 months between May 1995 and March 2002, 44.3% (2375/5356) were examined by a paediatrician who was unaware of the type of treatment used for each couple. Of all the children born, 12.2% (439/3618) in the ICSI group and 11.9% (207/1738) in the IVF group underwent a formal developmental assessment using the Bayley Scale of Infant Development (mental scale) by a paediatrician blinded to the type of treatment. Results There was no significant difference in maternal educational level, maternal age, gestational age, parity, birthweight, neonatal complication rate or malformation rate at 2 years between ICSI and IVF singletons, or between ICSI and IVF twins. No significant difference was observed in the developmental outcome using the Bayley scale at the age of 24-28 months (raw scores or test age) between ICSI children or IVF children. A multivariate regression analysis for the singleton children indicated that parity, sex (boys had lower scores than girls) and age had a significant influence on the test result, but that the fertility procedure (ICSI versus IVF) did not influence the test result. ICSI children from fathers with low sperm concentration, low sperm motility or poor morphology had a similar developmental outcome to that of children from fathers with normal sperm parameters. There were no significant differences between the initial cohort and the group lost to follow-up, nor between the psychologically tested and the non-tested group for a number of variables such as maternal educational level, birthweight in singletons and neonatal malformation rate. Although only some of the cohort of ICSI children were evaluated, a representative sample of both ICSI and IVF children was compared. Conclusions There is no indication that ICSI children have a lower psychomotor development than IVF children. Paternal risk factors associated with male-factor infertility were found not to play a role in developmental outcome.

Reproductive capacity of sperm obtained after germ cell transplantation in a mouse model

Abstract: BACKGROUND: The testicular stem cell transplantation technique has become an established research model in the mouse. This technique may also become useful for clinical applications. Therefore, it is necessary to investigate whether sperm obtained after testicular stem cell transplantation retain their full functional capacity and whether they are able to produce normally-developing embryos. This study aimed at evaluating the fertilizing and developmental abilities of sperm obtained after stem cell transplantation. METHODS: First, transplanted male mice were mated with females in order to evaluate in-vivo conception. Subsequently, functionality of sperm obtained after testicular germ cell transplantation was investigated by performing both IVF and ICSI. RESULTS: After in-vivo conception we found that in the control group 90% of the mice with a copulating plug became pregnant. In the experimental group only 35% of the mice with a copulating plug became pregnant (P = 0.006). After IVF, fertilization and blastocyst developmental rates were significantly lower in the transplanted group (P < 0.0001). Fertilization and blastocyst developmental rates after ICSI were comparable with control sperm. CONCLUSIONS: Our study showed that in the mouse, sperm obtained after stem cell transplantation are able to fertilize oocytes on the basis of assisted reproduction. It is recommended to further investigate this method in the human, as well as to investigate the post-implantation development of the embryo.

Comparison of the results of human embryo biopsy and outcome of PGD after zona drilling using acid Tyrode medium or a laser

Abstract: BACKGROUND: Zona pellucida opening for blastomere removal can be done by mechanical or chemical means, or by laser. So far, only limited data on the use of laser systems for zona drilling in cases of PGD are available. METHODS: Results of embryo biopsy and outcome of PGD in two periods were compared. In the first period, acid Tyrode medium was used for zona drilling. In the second period, zona drilling was performed by a 1.48 mm infrared laser. RESULTS: In the first period, 59 cycles resulted in 53 biopsy procedures with 356 biopsied embryos. In the second period, these numbers were 69 cycles, 69 biopsy procedures and 402 biopsied embryos. Fewer blastomeres were intact (95.2%) after zona drilling with acid Tyrode than after laser zona drilling (98.3%, P = 0.02). Rates of positive HCG (37.5% versus 35.5%), ongoing pregnancy rates (31.3% versus 25.0%) and ongoing implantation rates (18.9% versus 14.9%) did not differ. CONCLUSIONS: The use of a laser for zona drilling in cases of PGD is an easier procedure and results in more intact blastomeres. Since similar pregnancy rates are obtained, it is advantageous to use a laser for zona drilling. Further follow-up is necessary to prove the safety of this procedure.

Pregnancy outcome and neonatal data of children born after ICSI using testicular sperm in obstructive and non‐obstructive azoospermia

Abstract: BACKGROUND: Registries on outcome of ICSI pregnancies obtained with testicular sperm do not differentiate between obstructive (OA) and non-obstructive azoospermia (NOA). We evaluated the pregnancy outcome and neonatal data on children born after ICSI using testicular sperm of men with histologically proven OA or NOA. METHODS: Pregnancies obtained after ICSI using testicular sperm of men with defined NOA (n = 70) were compared with those of men with OA (n = 204). RESULTS: Multiple birth rates in NOA and OA couples, respectively, were 21 versus 27% (P = NS), overall preterm delivery rates were 38 versus 26% (NS), and prematurity rates were 24 versus 13% for singletons (NS) and 86 versus 54% for twins (relative risk 1.59, 95% confidence interval 1.04-2.42). Median gestational age for singletons was 38.3 versus 39.3 weeks, respectively (P < 0.05). The low birth weight rates were 34 versus 31%, respectively (NS). The early perinatal mortality rate was 66 versus 15 per 1000 births, respectively, (NS). Major congenital malformations were observed in 4 versus 3%, respectively, of the live born babies (NS). Prenatal karyotypes showed 7% de-novo abnormalities in the NOA group versus 1% in the OA group (NS). CONCLUSIONS: Our data do not show differences between NOA and OA pregnancies except for a strong tendency towards a lower gestational age in singletons and a higher percentage of premature twins in the NOA group. Although our data are based on a limited sample, the differences observed call for further analysis. Given the low pregnancy rates after ICSI with NOA, a multicentre study, differentiating NOA and OA patients, would be recommended.

Improving clinical preimplantation genetic diagnosis for cystic fibrosis by duplex PCR using two polymorphic markers or one polymorphic marker in combination with the detection of the ΔF508 mutation

Abstract: Cystic fibrosis (CF) is an autosomal recessive disease characterized by obstruction and chronic infection of the respiratory tract and pancreatic insufficiency. The first preimplantation genetic diagnosis (PGD) for CF was carried out in 1992. At our centre the first cycle was performed in 1993. However, the number of known CF mutations is >1000, so developing mutation-specific PCR protocols for PGD is unfeasible. This is why a number of marker-based duplex PCRs were developed at the single cell level. A duplex PCR of a mutation and one or two microsatellites is not only a diagnostic tool, but it can also be used as a control for allele drop-out and contamination. During PGD, embryos obtained in vitro are analysed for the presence or absence of a particular genetic disease, after which only embryos shown to be free of this disease are returned to the mother. In total, 22 PGD cycles with duplex PCR (IVS8CA/IVS17BTA, DF508/IVS8CA, DF508/IVS17BTA and D7S486/D7S490) were carried out in 16 couples, which resulted in four ongoing pregnancies and one miscarriage.

Preimplantation genetic diagnosis for Charcot-Marie-Tooth disease type 1A.

Abstract: Charcot-Marie-Tooth (CMT) disease is the 'common' name for a range of hereditary peripheral neuropathies. CMT1 is the most common form and is transmitted in an autosomal dominant manner. CMT1A maps to chromosome 17p11.2 and is caused, in the majority of cases, by a 1.5 Mb DNA duplication, that includes the peripheral myelin protein 22 (PMP) gene. This paper reports on preimplantation genetic diagnosis (PGD) for CMT1A in five couples. The CMT1A duplication was detected by fluorescent PCR analysis using polymorphic (CA)n markers localized within the duplication. Single-cell PCR on blastomeres allowed genetic analysis of embryos obtained after ICSI. Only healthy unaffected embryos were transferred to the uterus. PCR experiments with single EBV-transformed lymphoblasts or with research blastomeres allowed the evaluation of amplification efficiencies, as well as contamination and allele drop-out (ADO) rates for each PCR protocol. Three simplex PCR protocols (using one primer pair) and two duplex PCR protocols (using two primer pairs) were developed for CMT1A. Additionally, a protocol using all three primer pairs in triplex was also established. Thirteen clinical ICSI-PGD cycles were performed for five couples (12 simplex PCR cycles and one duplex PCR cycle), resulting in seven embryo transfers. Three singleton pregnancies ensued in two couples and three healthy babies were delivered. This report describes different fluorescent PCR-based tests which allow efficient and accurate single-cell level detection of the CMT1A duplication. On the basis of the presence of the healthy allele of the affected parent-to-be (and/or absence of the affected one), healthy embryos can be selected for transfer. The assays are suitable for PGD for other couples who present with the same CMT1A duplication [depending on their informativity for the (CA)n markers available] as described here.