Biomedical subjects

F Devreker

Publications and source records attributed to F Devreker.

At least 19 recordsLinked to original sources

PubMed2005

Should determination of the karyotype be systematic for all malformations detected by obstetrical ultrasound?

OBJECTIVE: The aim of this study was to determine whether karyotyping should be performed for every fetal malformation detected in low risk populations. METHODS: A karyotype was obtained from 428 fetuses examined over a 10-year period after fetal malformation was diagnosed using obstetrical ultrasound. These fetuses were separated into two groups, one with isolated malformations and the other with multiple malformations. The association between each type of malformation and the result of karyotype was evaluated. RESULTS: Forty-eight chromosomal abnormalities were encountered in 428 fetuses (11.2%). The karyotype was abnormal in 32/343 (9.3%) fetuses with isolated malformations and 16/85 (18.8%) fetuses with multiple malformations (p=0.022). The probability of an abnormal karyotype among the group of isolated malformation depended on the anatomical system involved (p<0.001). Our study demonstrated several isolated malformations without chromosomal abnormality (hydronephrosis with high obstruction, unilateral multicystic dysplastic kidney, gastroschisis, intestinal dilatation, meconium peritonitis, cystic adenomatoid malformation, pulmonary sequestration, tumor, vertebral anomaly). CONCLUSION: Each fetus with multiple malformations needs a chromosomal analysis. Within the group of isolated malformations, our study emphasizes that medical maternal history and the type of malformation need to be taken into account before performing a fetal karyotype.

Abnormalities, Multiple↗

PubMed2004

Effect of insulin-like growth factor-I during preantral follicular culture on steroidogenesis, in vitro oocyte maturation, and embryo development in mice.

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.

Animals↗

PubMed2002

Effect of preantral follicle isolation technique on in-vitro follicular growth, oocyte maturation and embryo development in mice.

BACKGROUND: The use of mechanical and enzymatic techniques to isolate preantral follicles before in-vitro culture has been previously described. The aim of this study was to assess the effect of the isolation procedure of mouse preantral follicles on their subsequent development in vitro. METHODS: Follicles were isolated either mechanically or enzymatically and cultured using an individual non-spherical culture system. Follicular development and steroidogenesis, oocyte in-vitro maturation and embryo development were assessed for both groups. RESULTS: After 12 days of culture, follicles isolated mechanically had a higher survival rate but a lower antral-like cavity formation rate than follicles isolated enzymatically. Enzymatic follicle isolation was associated with a higher production of testosterone and estradiol compared with mechanical isolation. A stronger phosphatase alkaline reaction was observed after enzymatic isolation, suggesting that follicles isolated enzymatically had more theca cells than those isolated mechanically. However, both isolation techniques resulted in similar oocyte maturation and embryo development rates. CONCLUSIONS: Enzymatic follicular isolation did not affect theca cell development. Follicular steroidogenesis was enhanced after enzymatic isolation but the developmental capacity of oocytes was comparable to that obtained after mechanical isolation.

Animals↗

PubMed2002

[The gynecology-obstetrics department].

The scientific and clinical activities of the Department of Obstetrics and Gynaecology have involved the three main subdivisions: the gynecological surgery, the obstetrics and fetal medicine, the endocrinology and the reproductive medicine. Minimal invasive surgery including laser assisted laparoscopy or robotic assisted surgery has been particularly developed. Endometriosis, a frequent and sometimes particularly invasive disease, and oncologic surgeries have been developed in collaboration with the digestive surgery department. The department has also contributed to the comprehension and treatment of prenatal pathologies such as premature labor and deliveries or the gestational diabetes. The department has supported the development of techniques to study the fetal well-being in utero: the prenatal echography, the chorionic villous sampling, the amniotic puncture or the cordocentesis for prenatal genetic diagnosis or fetal infectious contaminations, the CMV transmission more specifically. In endocrinology and reproductive medicine, the department has mainly developed the in vitro fertilization techniques. The prolonged embryo culture, the study of preimplantation embryo metabolism, the preimplantation genetic diagnosis and the cryopreservation of ovarian fragments to preserve fertility in women undergoing oncologic treatments represent the more recent developed topics. Finally, the security of viral transmission in assisted procreation and the treatment of these patients with chronic viral diseases (Hepatitis C or HIV) are another domain with important scientific activity.

Belgium↗

PubMed2001

Amino acids promote human blastocyst development in vitro.

Supplementation of culture media with amino acids has been shown to benefit preimplantation embryo development in several species. This randomized study analysed the in-vitro development of human embryos obtained after IVF in the presence or absence of a combination of amino acids from the 2- to 4-cell stage to the blastocyst stage. A total of 129 human embryos was randomly distributed between three serum-free chemically defined sequential media: (i) glucose-free Earle's balanced salt solution (EBSS) with glutamine (Gln) prior to morula stage, supplemented with glucose for blastocyst formation; (ii) glucose-free EBSS with glutamine and non-essential amino acids (AA) for cleavage stage development, and supplemented with all 20 AA for blastocyst formation (Earle's+AA); and (iii) a sequential commercial medium containing amino acids (K-SCIM). Embryos were individually cultured for successive periods of 24 h. On day 6 of development, blastocysts were differentially labelled and the numbers of trophectoderm and inner cell mass cells, mitoses and dead cells were examined. Blastocyst development was similar for the three sequential media. The mixture of AA significantly increased total blastocyst cell numbers from 61.8 +/- 4.2 with Earle's+Gln to 99.3 +/- 8.4 with Earle's+AA and 100.2 +/- 9.4 with K-SCIM (P = 0.005). This increase was present in both the trophectoderm and inner cell mass lineages (P < 0.02). Furthermore, the dead cell index was significantly lower with Earle's+AA (P = 0.047).

Amino Acids↗

PubMed2000

Noninvasive assessment of glucose and pyruvate uptake by human embryos after intracytoplasmic sperm injection and during the formation of pronuclei.

OBJECTIVE: To improve in vitro culture conditions and human embryo selection before transfer after IVF with intracytoplasmic sperm injection (ICSI). DESIGN: A controlled, randomized, prospective study. SETTING: University hospital-based IVF-ET program. PATIENT(S): Couples undergoing ICSI. INTERVENTION(S): Culture of human embryos in the presence of 1 mM or 5.56 mM glucose and metabolic measurements with the use of noninvasive microfluorescence assays immediately after ICSI to the time of transfer. MAIN OUTCOME MEASURE(S): Embryo development, implantation rate, and glucose and pyruvate uptake. RESULT(S): Fertilization rates, early embryo development, and implantation rates were not significantly different between 1 mM and 5.56 mM glucose. Pyruvate uptake was significantly higher during the formation of the pronuclei, at 15 +/- 0.7 and 11.4 +/- 1.3 pmol/embryo/h for fertilized and unfertilized oocytes, respectively. Pyruvate uptake did not correlate with cleavage stage or embryo morphology. However, during the second day of incubation, pyruvate uptake was significantly higher for the untransferred embryos of pregnant women compared with nonpregnant women, at 17.9 +/- 1.5 and 10.8 +/- 1.0 pmol/embryo/h, respectively. CONCLUSION(S): The increased level of pyruvate uptake during fertilization reflects the increased demand for energy necessary for the formation of the pronuclei. However, the metabolic measurements could not improve the selection of embryos with the best implantation potential. Finally, the reduction of glucose concentration in the culture medium failed to improve embryo viability.

Embryo Implantation↗

PubMed2000

In vitro development and metabolism of the human embryo up to the blastocyst stage.

The preimplantation period begins with the fertilisation of the oocyte and ends with the formation of the blastocyst. During this period, several major events occur resulting in an embryo composed of pluripotent cells. These morphological changes correspond to changes in the embryonic metabolism. The cleavage stages are characterised by a low metabolism and the inability of the embryo to metabolise glucose. After the activation of the embryonic genome, there is a surge in the embryonic metabolism with increased demand for ATP. The embryo is then able to metabolise glucose. Recently, the importance of amino acids has been highlighted by experiments with mouse, hamster and bovine embryos. Amino acids have also been reported to benefit human embryo development in vitro. Some growth factors have been shown to play a role in human embryo development too. The importance of lipids or vitamins, however, is poorly investigated. Culture media have been developed to improve preimplantation development, but more information is required for adapting culture condition to embryonic requirements which hopefully will improve the outcome of in vitro fertilisation (IVF).

Amino Acids↗

PubMed1999

Comparison of two elective transfer policies of two embryos to reduce multiple pregnancies without impairing pregnancy rates.

A first elective transfer policy of two embryos based solely on embryo morphology was compared to a more restrictive policy transferring two embryos to all patients aged < 35 years with less than three previous cycles to reduce the incidence of multiple pregnancies. With a significant reduction in the number of triple transfers from 72.4 to 44.3%, the delivery rates were similar for both policies, 31 and 32.1%. However, the multiple pregnancy rates per transfer significantly decreased from 12.5 to 7.8% (P < 0.05). Of 99 pregnancies, only 24.2% were multiple including 1% of triplets compared to 40.7% multiple pregnancies including 6.7% of triplets for the first policy. Forty-eight transfers of two average embryos with the new policy were compared to 264 transfers of three average embryos with the old policy. Multiple pregnancy rates per transfer were significantly reduced by a third from 23 to 8% (P < 0.05) without a reduction of the pregnancy rates (42 and 48%). This study demonstrated that elective transfer of two embryos reduced the number of multiple pregnancies without impairing the pregnancy rates even with the transfer of average embryos.

Adult↗

PubMed1999

Selection of good embryos for transfer depends on embryo cohort size: implications for the 'mild ovarian stimulation' debate.

Embryo quality evaluated by the embryo morphology is a critical parameter in human in-vitro fertilization (IVF) and embryo transfer. It determines which and how many embryos will be replaced, as pregnancy rates are directly related to number and quality of transferred embryos. This retrospective analysis included 1301 IVF and embryo transfer cycles to identify which factors influenced embryo quality. Embryo quality did not correlate with maternal age, causes of infertility, ovarian stimulation parameters or embryo cohort size. However, the mean score of transferred embryos was significantly higher for patients with more than five embryos compared to fewer than five embryos (P < 0.001), irrespective of maternal age. Patients tended to produce a similar embryo quality from cycle to cycle, r = 0.33 (P < 0.001) for the embryo cohort and r= 0.47 (P < 0.001) for the transferred embryos. Poor embryo morphology probably reflects oocytes with compromised development competence and could be an independent factor of infertility. Furthermore, a large embryo cohort was the main factor increasing the chances of at least one good embryo in the cohort.

Adult↗

PubMed1999

Effects of taurine on human embryo development in vitro.

Glutamine and taurine are reported to be beneficial for mouse embryo development in vitro, and we have recently shown that glutamine improves human blastocyst formation in vitro. This randomized study compared the development of supernumerary human embryos in the presence of 1 mmol/l glutamine and/or 5 mmol/l taurine from the 2-4-cell stage to the blastocyst stage. Blastocyst development and cell numbers were similar in the presence of glutamine or taurine: 52.6% and 58.3% of the embryos reached the blastocyst stage, respectively. Pyruvate uptake was similar in the presence of glutamine or taurine throughout development, as was lactate production after the 8-cell stage. Before this stage, lactate production was 4-fold higher in the presence of taurine (P < 0.001). The proportion of embryos reaching the blastocyst stage was similar with glutamine alone or with glutamine and taurine (62.5% and 47.2% respectively), as were the blastocyst cell numbers (63.0 +/- 4.6 and 61.0 +/- 5.1 respectively). In conclusion, taurine supports development of 2-4-cell human embryos to the blastocyst stage, although it does not further augment the beneficial effects of glutamine.

Blastocyst↗

PubMed1999

[In vitro fertilization at the Erasme Hospital: 10 years and 1000 pregnancies later...].

This contribution summarize ten years of in vitro fertilization of clinical work. Activity growth, improvements of results (mean fertilization rate increased from 45% to 58%, fertilization failure dropped from 18% to 7%, pregnancy chances gains 9% to reach 44% per trial) and new treatments possibilities (severe male infertility) thanks to the ICSI technic were the major characteristics of this last ten years. The original anonymous oocyte donation program with donors permutation initiated as soon as 1990 has imposed itself due to it's exceptional efficiency with a pregnancy rate of 95% per oocyte pick up on a population of 46 donors and 145 recipient cycles. Thanks to the large population studied (4028 cycles, 1071 pregnancies), the tendencies in human fecundity (impact of age) and the risks linked to multiples pregnancies could be highlighted, stressing the importance of future developments presented in the other contributions following this general presentation of results.

Adult↗

PubMed1999

[Evolution of ovarian stimulation in in vitro fertilization].

This paper reviews the different treatments of ovarian stimulation for in vitro fertilization (IVF). It emphasizes the recent development of new molecules, including recombinant gonadotrophins and GnRH antagonists. Because of their higher purity, recombinant gonadotrophins are theoretically less immunogenic than the urinary forms. Their preparation mode ensures a better batch to batch consistency. Their clinical use in IVF seems to be associated with a higher number of developing follicules and retrieved oocytes, but pregnancy rates are comparable to those obtained after ovarian stimulation with urinary gonadotrophins. The GnRH antagonists induce a direct inhibition of the pituitary gonadotrophin secretion. In association with an ovarian stimulation with gonadotrophins, they efficiently prevent premature LH surges when administered during the end of the follicular phase. The GnRH antagonists are still in clinical evaluation phase and the optimal protocol and dose still to be defined. They should become available in the coming year. The risks related to the controlled hyperstimulation together with the reduction of the number of transferred embryos has recently led "soft stimulation" to a reevaluation of the stimulation protocols towards a simplified procedure. However, the validity of this attitude could be in opposition with the wish to limit the number of transferred embryos since embryo quality seems to be directly related to the total number of embryos.

Clomiphene↗

PubMed1999

[Diminishing the risk of multiple pregnancies in in vitro fertilization: from selective transfer of two embryos to that of one blastocyst?].

The risk of multiple pregnancy after IVF needs to be drastically reduced. Several policies can be applied including the transfer of a maximum of three embryos to all patients, the fertilization of a maximum of three oocytes or a selective reduction of the number of transferred embryos. The first policy previously applied at the Fertility Clinic at Erasme Hospital until 1996, transferred two good quality embryos to patients with at least three good embryos. If this policy demonstrated that patients with two transferred embryos had similar chances of pregnancies compared to patients with three transferred embryos, it failed to sufficiently decrease the number of multiple pregnancies. The second policy applied since 1997, transferring a maximum of two average or good embryos to all patients aged under 35 years and with less than 3 previous attempts, demonstrated that while preserving the chances of pregnancy for these patients, it decreased by 20% the number of multiple pregnancies and almost eliminated triplets. With the improvement of culture media, it is now possible to culture embryos in vitro for a longer period and therefore transfer embryos with proven viability at a time corresponding more to in vivo physiological conditions. The implantation rates for these embryos, for patients with at least 4 previous attempts can reach 40%. If these results persist, it would be possible to transfer blastocysts to all patients and perhaps move on to the replacement of a single embryo, a policy that will practically eradicate all multiple pregnancies.

Adult↗

PubMed1999

[Aspects of scientific research and technical progress in human fertility].

The development of an outstanding in vitro fertilization program greatly benefits from the contribution of research because it remains an unfailing source of questions on human reproduction, as much in the fields of physiology and pathology as in those of psychology and sociology. This paper shows five major themes that are tackled by the laboratory of biology and psychology of human fertility and the Fertility Clinic, whether it's endocrinology (the ovarian renin and angiotensin regulation), cellular metabolism (embryo metabolism), genetics (preimplantation genetic diagnosis) or cancerology (ovarian tissue conservation before or after chemo- or radiotherapy), all of these are crossed by the fifth (the psychological and ethical aspects of in vitro fertilization) which gives a human dimension to the biological work, since it's a very special biology that it's our own reproduction, the very base of the specie's survival.

Cryopreservation↗

PubMed1998

Glutamine improves human preimplantation development in vitro.

OBJECTIVE: To study the effect of glutamine on human preimplantation embryo development in vitro. DESIGN: A randomized, controlled, prospective study of 138 normally fertilized and nontransferred human embryos. On day 2 after fertilization, the embryos were allocated randomly to glucose-free medium with or without 1 mM of glutamine. SETTING: A university hospital-based IVF-ET program. PATIENT(S): Couples undergoing IVF treatment. INTERVENTION(S): Embryo culture. MAIN OUTCOME MEASURE(S): Blastocyst formation, trophectoderm and inner cell mass numbers, and pyruvate uptake and lactate production by individual embryos. RESULT(S): A higher proportion of embryos reached the morula (89% versus 68%, respectively) and blastocyst (71% versus 54%, respectively) stages when cultured with glutamine compared with embryos cultured without glutamine. Blastocyst cell numbers were not statistically significantly different for embryos grown in the presence or absence of glutamine. Pyruvate uptake and lactate production were higher in the presence of glutamine throughout development; these increases were statistically significant at the blastocyst stage. CONCLUSION(S): This study demonstrates that supplementation of the culture medium with glutamine is beneficial for human preimplantation embryo development in vitro, increasing the proportion of embryos that develop to the morula and blastocyst stages.

Blastocyst↗

PubMed1998

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

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.

Adnexal Diseases↗

PubMed1998

Comparison of pregnancy outcome after intracytoplasmic sperm injection and in-vitro fertilization.

The aim of this study was to compare pregnancy characteristics and perinatal outcome of intracytoplasmic sperm injection (ICSI) pregnancies with pregnancies obtained after in-vitro fertilization (IVF). Retrospectively, 145 ICSI pregnancies were matched with 145 IVF pregnancies using the last menstruation data. The main outcome measures were preclinical and clinical abortions, ectopic pregnancies, multiple gestations, prenatal morbidity, prematurity, Caesarean section, birthweight, perinatal mortality and malformations for singletons, twins and triplets. Although patients were significantly younger (P < 0.001) in ICSI (31 years) than in IVF (33 years), their infertility duration (5 years) was similar. The mean number of transferred embryos (2.7 embryos per transfer) was similar in IVF and ICSI. The rates of preclinical (15%) and clinical abortions (11% in ICSI versus 15% in IVF) were not different. Four ectopic pregnancies were observed in the IVF group and none in the ICSI group. In ICSI, two minor malformations were detected and two therapeutic abortions were performed respectively for polymalformations and suspicion of cystic fibrosis. The rate of congenital malformation was 2.8% in ICSI and 2.2% in IVF. In this last group, one therapeutic abortion for malformation of neural tube was performed and two minor malformations were detected. The rate of aborted embryonic sacs before 16 weeks of gestation was not significantly lower in ICSI compared with IVF (13.7% versus 20%). The rate of multiple gestations was similar in both groups (31% in IVF and 35% in ICSI). The number of Caesarean sections was similar in IVF and in ICSI and was twice as frequent for twins versus singletons. The number of singletons born by Caesarean section was 21% after ICSI and 17% after IVF. Mean birthweights and gestational ages at birth for twins were significantly higher (P < 0.05) in ICSI than in IVF (2488 versus 2281 g and 36.5 versus 35.5 weeks). This difference was not observed for singletons. In conclusion, pregnancy characteristics and perinatal outcome after ICSI showed no increase in the number of pathologies in comparison with IVF.

Adult↗

PubMed1997

Effects of glutamine and taurine on preimplantation development and cleavage of mouse embryos in vitro.

Glutamine and taurine are reported to improve the development of mouse embryos in vitro, and glutamine is a component in CZB and KSOM, media optimized to overcome the 2-cell block in outbred strains of mice. Here we have studied the development of embryos from F1 hybrid female mice in CZB and KSOM, from the zygote to the blastocyst stage, in the presence and absence of 1 mM glutamine and/or 5 mM taurine. Blastocyst formation, rate of development, number of trophectoderm and inner cell mass cells, mitosis, and cell death were examined. Glutamine had no effect on the proportion of embryos developing to the blastocyst stage, but it significantly reduced cell number at the blastocyst stage. The trophectoderm was the lineage most affected, showing increased levels of cell death. Changing the media after 48 h, to remove any possible buildup of toxic metabolites, did not reverse the inhibition by glutamine. Taurine had no effect on blastocyst development of cell number. Development in glutamine-free KSOM (KSOM-Gln) was compared to that in standard CZB and KSOM with glutamine and M16. Early cleavage was slower in M16, but by Day 5 over 84% of embryos had developed to the blastocyst stage in all media, with a similar cell number in M16, CZB, and KSOM. Cell numbers in blastocysts cultured in KSOM-Gln were significantly higher than in the other media and approached those found in vivo.

Animals↗