Search PubMed⌕ Search

Biomedical subjects

J Selva

Publications and source records attributed to J Selva.

At least 19 recordsLinked to original sources
PubMed1998

Chromosome 21 detection in human oocyte fluorescence in situ hybridization: possible effect of maternal age.

PURPOSE: The purpose of this study was to evaluate, among 100 uncleaved oocytes, the incidence of numerical and structural chromosome 21 and X abnormalities and to analyze the influence of various factors, such as in vitro (IVF) indications, follicle stimulation protocols, and women's age. METHODS: We investigated 150 uncleaved oocytes from 128 patients after an IVF attempt. After cytogenetic analysis (Giemsa) 100 oocytes (66%) were selected for fluorescence in situ hybridization (FISH). Fluorescent probes for human chromosomes X and 21 were used simultaneously according to standard procedures for their hybridization and detection. RESULTS AND CONCLUSIONS: We analyzed by the FISH protocol 100 metaphase II oocytes with 22 to 25 chromosomes. Our results demonstrate a high rate of disomy for chromosome 21 in human oocytes. Among them, eight were disomic (8%) and three were nullosomic (3%) for chromosome 21. Only one disomy of chromosome X was noted. The various indications of IVF and the different folliculogenesis stimulating protocols did not seem to influence the results but suggested a correlation between the maternal age and the aneuploidy rate of chromosome 21.

Adult↗
PubMed1997

Pregnancy outcome after artificial insemination or IVF with frozen semen donor: a collaborative study of the French CECOS Federation on 21,597 pregnancies.

OBJECTIVE: To assess pregnancies and conceptus after artificial insemination (AID) or IVF with frozen semen donor (IVF-D) on sufficiently large study population in order to distinguished minor variations. STUDY DESIGN: From 1987 to 1994, all pregnancies obtained after AID or IVF-D were registered prospectively in the French CECOS Federation data base. Different factors were recorded for this study: first menarche age of the recipient women, cycle length, insemination date in the conception cycle, maternal age at delivery, hormonal treatments, donor age, sperm conservation length and follow up of the pregnancy: miscarriage, tubal pregnancy, time at delivery, sex of the foetus, weight, malformation. RESULTS: 21,597 pregnancies obtained after AID and 3381 after IVF-D were registered. 2% were lost to follow up. Foetal loss rate is 18% after AID and 21.5% after IVF-D (p < 0.001). The tubal pregnancy rate is 0.9% after AID and 1.7% after IVF-D (p < 0.0001). 18,128 children were born after AID and 3313 after IVF-D. After AID, the twin pregnancy rate is 6.9% and the multiple pregnancy (> or = 3 foetus) rate is 0.7%. After IVF-D, these rates are 24.8% and 4.2% respectively (p < 0.0001). After AID the mean weight at delivery, sex ratio, premature rate, intra uterine growth retardation rate are not different from national rates published in 1995. The foetus malformation rate (including medical abortions) is 1.9% after AID and 2.7% after IVF-D (p < 0.009). After AID the trisomy 21 rate increases with the mother age but also with the donors age if the maternal age is equal. The birth defects rate is not different from those registered in Paris, Strasbourg and Marseille. The birth defects rate observed after IVF-D is not different from the rate observed after IVF with husband semen. (2.74% versus 2.99%; p = 0.16). CONCLUSION: After AID the miscarriage and tubal pregnancy rate, the children's weight, the premature rate is not different from that of the general French population. Sex ratio is normal as is the global malformation rate. The multiple pregnancy rate (x 7 for twin and by 10 for multiple pregnancies more than 3 foetus) is high, showing the influence of ovulation induction treatment. The birth chromosomal abnormalities rate is normal and correlated not only to the mother's age but also to the donor's age. This result without clear biological explanation will require further verification in a greater population. Practically speaking, these observations encourages lowering the age limit for semen donors less than 45 years. IVF-D practice instead of AID doubles the tubal pregnancy rate (0.9% versus 1.7% and increases the twin pregnancy rate by 2.5% and the multiple pregnancy (> or = 3 fetus) rate by 3. It is necessary to promote good practice for AID for which the pregnancy rate is very different from one centre to another within the centres with AID low results a too high rate of IVF-D. Finally we can say that pregnancies from IVF-D or IVF with husband semen are not significantly different. In other words pregnancy outcome is not changed after sperm cryopreservation.

Adult↗
PubMed1997

Incidence of AZF (azoospermia factor) deletions and familial forms of infertility among patients requiring intracytoplasmic spermatozoa injection (ICSI).

PURPOSE: The aim of our study was to determine the incidence of AZF deletions and familial forms of infertility suggesting autosomal mutations among patients requiring intracytoplasmic sperm injection with ejaculated sperm. METHODS: Cases with obstructive pathologies were excluded; 81 patients were classified according to the numeration of spermatozoa. The distribution was as follows: 10 cases with normal numeration (greater than 20 million/ml) (group 1), 10 cases with between 10 and 20 million/ml (group 2), 6 cases with between 5 and 10 million/ml (group 3), 15 cases with between 1 and 5 million/ml (group 4), 29 cases with less than 1 million/ml (group 5), and 11 azoospermic patients (group 6). The infertility of 11 of the 81 patients might be explained by testicular ectopy. RESULTS: We found two deletions limited to the AZFc region among our 81 infertile patients--one deletion in group 5 and one deletion in group 4 (both groups of oligozoospermic patients)--and no deletion in the groups with normal or subnormal numerations. We found six familial forms of infertility. We did not find any AZF deletion, neither in these 6 patients nor in the 11 with testicular ectopy. The identification of these families of infertile men will allow research of autosomal genes involved in male infertilities. CONCLUSIONS: It is important to test deletions of the AZFc region for oligozoospermic patients, and familial forms of infertility do not seem to concern the same individuals.

Chromosome Deletion↗
PubMed1997

Cryopreserved immature mouse oocytes: a chromosomal and spindle study.

PURPOSE: Cryopreservation of human oocytes might provide an alternative approach to freezing supernumerary embryos obtained during IVF. This process, performed on immature denuded prophase 1 mouse oocytes, was investigated. METHODS: We first investigated the capacity of frozen, immature, murine oocytes to continue in vitro maturation after thawing. We then evaluated the risk to offspring from chromosomal damage by cytogenetical and cytological (spindle) analysis. Finally, we attempted to determine the reasons for and the stage of maturation failure. RESULTS: A total of 700 immature oocytes was frozen, 629 (90%) were recovered intact after thawing, and 53% extruded the first polar body, versus 74% for the control group. Freezing was not accompanied by an increase in aneuploidy in maturing oocytes (18 and 15% for thawed and control oocytes, respectively). Consequently, the first meiotic division occurred normally, without an increase in nondisjunction. Spindle analysis demonstrated only a few abnormalities (15 and 2% for thawed and control oocytes, respectively) incompatible with further development. Oocytes arrested during in vitro maturation were mainly at the metaphase I stage (64 and 76% for thawed and control oocytes, respectively). Whereas 17% of thawed oocytes were blocked before the formation of the first meiotic spindle, this never occurred in the control group. CONCLUSIONS: Immature murine oocytes can withstand cryo-preservation, which is encouraging for future human application of this technique.

Animals↗
PubMed1996

[Intracytoplasmic injection of spermatozoa].

Management of male infertility has been totally changed with the development of intracytoplasmic sperm injection (ICSI). This technique, used for in vitro fertilization, consists in injecting a single spermatozoa into the ovum. Intracytoplasmic sperm injection can be proposed in case of severe male sterility (oligoasthenospermia) or after repeated failure of in vitro fertilization. Satisfactory rates of fecondation and pregnancy have been obtained. Results have also been obtained with sperm taken from the epididymis or testis. The risks involved concern the transmission of poorly understood genetic defects leading to the infertility. The rates of reported malformations and chromosome anomalies are quite low. Intracytoplasmic sperm injection can be useful in managing most cases of male infertility which to date have had to rely on donor sperm. Long-term results have not yet been obtained.

Female↗
PubMed1996

Premature progesterone elevation does not alter oocyte quality in in vitro fertilization.

OBJECTIVE: To clarify whether premature P elevation during controlled ovarian hyperstimulation (COH) for IVF-ET affects adversely oocyte-embryo quality. DESIGN: Controlled clinical study. PATIENTS: We studied 102 fertile donors undergoing 106 oocyte retrievals and 117 recipients undergoing 162 ET. INTERVENTIONS: Donors underwent COH with a time-release GnRH agonist and hMG. All recipients had inactive or absent ovaries and were primed with E2 and P. MAIN OUTCOME MEASURES: Measurement of LH, P and E2; characteristics of COH; cleavage, pregnancy, and implantation rates. RESULTS: According to donors' plasma P levels on the day of hCG, two groups were defined: P < or = 0.9 ng/mL (conversion factor to SI unit, 3.18), group A, and P > 0.9 ng/mL, group B. Similar results of cleavage (65% and 72%), clinical (30% and 29%), and ongoing pregnancy (20% and 18%), and implantation (14% and 15%) rates were observed in both groups, respectively. CONCLUSIONS: The lack of difference in cleavage, pregnancy, and implantation rates between both groups suggests that preovulation increase in P production does not alter oocyte-embryo quality. Hence, the reported adverse effects on IVF outcome of pre-hCG elevation of P is likely to reflect an impaired endometrial receptivity in the high P group.

Adult↗
PubMed1996

Incidence of birth defects after artificial insemination with frozen donor spermatozoa: a collaborative study of the French CECOS Federation on 11,535 pregnancies.

Artificial insemination using cryogenically preserved spermatozoa has been widely used in human reproduction for several decades. No evaluation of the resulting pregnancies and conceptions has been undertaken in sufficiently large study populations for minor variations to be distinguished. This study involves 11,535 pregnancies conceived by artificial insemination using donor spermatozoa and followed from the time that pregnancy was diagnosed. The pregnancies followed a normal course with, in particular, no excessive fetal losses. While the global incidence of birth defects was similar to that of natural conception, our observations raise doubts concerning trisomy 21. The frequency of trisomy 12 was somewhat elevated when compared with French malformation registries. A recruitment bias could, in part, explain this discrepancy, but donor age cannot be excluded as an influencing factor.

Adult↗
PubMed1995

Effects of cooling and equilibration in DMSO, and cryopreservation of mouse oocytes, on the rates of in vitro fertilization, development, and chromosomal abnormalities.

In a previous study, we have shown that the cryopreservation of mouse oocytes caused increases in the rates of degeneration and of digynic polyploid embryos, while the fertility of frozen-thawed oocytes was decreased. In this study, we have attempted to determine the different stages in the complete freezing-thawing process which are deleterious for the oocytes and the subsequent zygotes. IVF assays showed that DMSO decreased the fertility of oocytes, whereas cooling to 0 degrees C had no effect. DMSO, used at 0 degrees C, was less deleterious for oocytes. Thus, the prefreezing manipulations seem to be important for the quality and fertility of oocytes. However, neither DMSO nor cooling increased the incidence of chromosomal abnormalities in embryos obtained from inseminated exposed oocytes. Therefore, the increased frequency of polyploidy observed in embryos after the cryopreservation of mouse oocytes must correspond to disruption occurring during the freezing-thawing process.

Aneuploidy↗
PubMed1995

Chromosome 18 analysis by fluorescence in situ hybridization (FISH) in human blastomeres of abnormal embryos after in vitro fertilization (IVF) attempt.

We performed fluorescence in situ hybridization (FISH) with a chromosome 18-specific probe on human abnormal cleaved embryos, fertilized either by two spermatozoa and exhibiting three pronuclei (3 PN) or normally fertilized and exhibiting two pronuclei (2 PN) with subsequent severe fragmentation and/or blocking. The aim of the study was to evaluate the incidence of chromosome 18 anomalies among these embryos in order to evaluate the FISH efficiency on such material and to obtain more precise and complete data than those obtained with classical cytogenetic analysis. For the 3 PN cleaved embryos, FISH confirmed the frequent regulation towards diploidy (25 per cent) and the high frequency of mosaics (53 per cent). For the 2 PN blocked or damaged embryos, FISH permitted chromosome evaluation, which was otherwise impossible with classical cytogenetic techniques: we also found a high mosaic frequency (45 per cent) with these embryos. If this frequency were the same for normally developing embryos, it would be a major obstacle to the reliability of either chromosomal or genetic preimplantation diagnosis.

Blastomeres↗
PubMed1995

Cytogenetic analysis of uncleaved oocytes after intracytoplasmic sperm injection.

PURPOSE: This work analyzes the causes of cleavage failure after intracytoplasmic sperm injection (ICSI) and the effect of the procedure on the chromosomes of the oocytes. METHODS: Ninety-seven uncleaved oocytes from 39 patients with severe male infertility or repeated IVF failure were fixed; 79 were analyzable. We checked the decondensation stage of spermatozoa nucleus and the chromosomal abnormalities of the oocytes. RESULTS: Among the fixed oocytes, the spermatozoa nucleus was present in 97% of the cases, and it was undecondensed in 89% of the cases, showing no evolution at all. A low rate (2.6%) of premature chromosome condensation (PCC) of the spermatozoa and a low rate (2.5%) of female diploïdy were observed. Among the oocytes that could be karyotyped, we observed a high rate (45%) of chromosome breakage. CONCLUSION: ICSI fertilization failure was due mostly to the complete lack of evolution of the spermatozoa nucleus. Oocyte selection before ICSI seemed to lower the PCC rate. The high rate of oocyte chromosomal breakage rate has to be confirmed.

Chromosome Aberrations↗
PubMed1995

Scheduled administration of a gonadotrophin-releasing hormone antagonist (Cetrorelix) on day 8 of in-vitro fertilization cycles: a pilot study.

To assess in a pilot study the ability of a single injection of a GnRH antagonist (Cetrorelix) to prevent premature luteinizing hormone (LH) surges in an in-vitro fertilization (IVF) embryo transfer programme when administered on a fixed day in the late follicular phase, ovarian stimulation was carried out in 11 women with two ampoules of human menopausal gonadotrophin per day beginning on day 2 of the menstrual cycle. A 3 mg dose of Cetrorelix was administered on day 8 of the stimulation cycle. A second injection was administered 72 h later if ovulation was not triggered in the meantime. We did not observe a premature LH surge in any of the cycles studied. The injection of 3 mg Cetrorelix was capable of preventing LH surge in all the patients studied, introducing a very simple treatment protocol. Among the patients who received two injections (n = 3), the day of the first administration was delayed in two subjects due to slow follicular maturation kinetics. Out of 11 patients, 10 had an embryo transfer. Four clinical pregnancies were obtained (40% per embryo transfer), of which 3 are ongoing (30% per embryo transfer). A simple administration protocol for a new GnRH antagonist (Cetrorelix) was able to prevent LH surges in the 11 patients studied.

Adult↗
PubMed1994

The single or dual administration of the gonadotropin-releasing hormone antagonist Cetrorelix in an in vitro fertilization-embryo transfer program.

OBJECTIVE: To assess the ability of a GnRH antagonist (Cetrorelix, Asta Medica AG, Frankfurt, Germany) to prevent premature LH surges in an IVF-ET program using a simple protocol with one or two administrations. DESIGN: Controlled ovarian hyperstimulation was carried out in 17 women with three ampules a day of hMG, starting on day 2 of the menstrual cycle. A dose of 5 mg of Cetrorelix was administered when plasma E2 levels were between 150 and 200 pg/mL (conversion factor to Sl unit, 3.671) per follicle of > or = 14 mm. A second injection was performed 48 hours later if the triggering of ovulation was not decided in the meantime. RESULTS: Six patients received one injection and 11 patients received two administrations. Plasma LH levels showed a marked decrease and remained low after the administration of the GnRH antagonist. In six patients, the first administration of Cetrorelix was performed when a significant rise in LH plasma level was present. Even in these patients the GnRH antagonist was able to prevent an LH surge. The tolerance of the product was good. Six clinical pregnancies were obtained, of which four are ongoing (25% per ET). Two ongoing pregnancies were obtained after the transfer of a frozen-thawed embryo (35.3% per retrieval). CONCLUSIONS: The GnRH antagonist Cetrorelix in a simple, unique or dual administration, protocol was able to prevent premature LH surge in all of the 17 patients studied. If these results are confirmed by larger, randomized studies, the good tolerance and efficacy that we observed suggest a bright future for this product is assisted reproductive technologies.

Adult↗
PubMed1993

Cytogenetic analysis of human oocytes after subzonal insemination.

Subzonal insemination has been proposed to achieve fertilization in cases where standard in vitro fertilization has failed. We present the results of chromosome analysis of oocytes after subzonal insemination. Our data suggest that the main cause (76 per cent) of the absence of cleavage after subzonal insemination is the total absence of sperm nucleus evolution of the injected spermatozoa. Our results also suggest that spermatozoa chromatin development is normal after subzonal insemination. Aneuploidy does not seem to be increased in zygotes after subzonal insemination. However, polyploidy was often more important than predicted by the observation of pronuclei (PN). Pronucleus development might be asynchronous and can appear earlier or later than after standard IVF. The cytogenetic risk after subzonal insemination might therefore be triploidy (if a triploid egg is transferred, because only 2 PN were seen) rather than aneuploidy or structural abnormalities.

Cell Nucleus↗
PubMed1993

Per-urethral transvesical first-trimester amniocentesis.

Early amniocentesis (before 13 weeks' gestation) using a per-urethral transvesical route is studied. Eight samples were obtained in eight patients scheduled for elective termination of pregnancy. The volume of amniotic fluid averaged 12.5 +/- 7.8 ml. Culture was successful in all samples. In one case, culture was achieved with only 2 ml of amniotic fluid. The amniotic fluid can be easily obtained via the per-urethral transvesical route. We conclude that early per-urethral amniocentesis before 13 weeks amenorrhea may be an alternative to the transabdominal route. A clinical trial should be carried out in order to evaluate both techniques.

Amniocentesis↗