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A van Steirteghem

Publications and source records attributed to A van Steirteghem.

9 recordsLinked to original sources
PubMed2005

A lower ongoing pregnancy rate can be expected when GnRH agonist is used for triggering final oocyte maturation instead of HCG in patients undergoing IVF with GnRH antagonists.

BACKGROUND: Eliciting an endogenous LH surge by GnRH-agonist for the induction of final oocyte maturation may be more physiological compared with the administration of HCG. However, the efficacy of this intervention in patients treated for IVF with GnRH antagonists remains to be assessed. METHODS: 106 patients were randomized to receive either 10 000 IU urinary HCG or 0.2 mg Triptorelin for triggering final oocyte maturation. Ovarian stimulation for IVF was performed with a fixed dose of 200 IU recombinant FSH and GnRH antagonist was started on stimulation day 6. Luteal phase was supported with micronized vaginal progesterone and oral estradiol. The study was monitored continuously for safety and stopping rules were established. RESULTS: No significant differences were present in the number of cumulus-oocyte complexes retrieved, in the proportion of metaphase II oocytes, in fertilization rates or in the number and quality of the embryos transferred between the two groups. However, a significantly lower probability of ongoing pregnancy in the GnRH agonist arm prompted discontinuation of the trial, according to the stopping rules established (odds ratio 0.11; 95% confidence interval 0.02-0.52). CONCLUSIONS: Lower probability of ongoing pregnancy can be expected when GnRH agonist is used for triggering final oocyte maturation instead of HCG in patients undergoing ovarian stimulation for IVF with GnRH antagonists.

Adult↗
PubMed2005

HLA-matched embryos selected for siblings requiring haematopoietic stem cell transplantation: a psychological perspective.

Allogeneic haematopoietic stem cell transplantation (HSCT) is a treatment for a number of acquired and congenital diseases. An important factor in the outcome of the treatment is the degree of human leukocyte antigen (HLA) compatibility between patient and donor. HLA identical siblings therefore provide the best chance for the recipient. Preimplantation genetic diagnosis (PGD) can be used to select HLA identical embryos if there is no HLA compatible sibling in the family. The Centre for Reproductive Medicine considered it morally justified to give medical assistance to couples in need of an HLA matched sibling. Two considerations played an important role in this respect: (i) the use as a donor should not be the only parents' motive for having the child and (ii) IVF and HLA typing on the embryos would be less of a burden for the parents than other alternatives. Since the first request in 2000, 12 couples have been referred for psychological counselling. The motivation of four couples will be discussed in depth. The validity of the arguments will be checked against the experience of the actual cases. The consequences of the treatment on the welfare of the future donor child will be discussed.

Adult↗
PubMed2001

[Twenty years of in vitro fertilization: realization and questions for the future].

IVF is a well-established procedure for the treatment of longstanding infertility due to tubal disease, endometriosis, unexplained infertility or certain types of infertility involving a male factor. IVF can also be applied to couples requiring oocyte donation. Conventional IVF involves several related procedures: patient selection, ovarian stimulation, oocyte retrieval, semen preparation, insemination of cumulus-oocyte complexes, assessment of fertilization, assessment of embryo cleavage, replacement to the uterus of mostly two or three embryos, cryopreservation of excess embryos and establishment of pregnancy. GIFT and ZIFT are related techniques, suitable in couples with at least one healthy Fallopian tube. Conventional IVF is a potentially successful procedure in patients with tubal and unexplained infertility. However, fertilization may fail in couples with certain forms of andrological infertility, especially those in which sperm function is severely deficient. Techniques of assisted fertilization--partial zona dissection (PZD) and subzonal insemination (SUZI)--have been used with limited success to treat couples with severe andrological infertility who could not be helped by conventional IVF. ICSI--the injection of a single spermatozoon into the cytoplasm of a fertilizable metaphase II oocyte--has proved to be more efficient than PZD and SUZI for the alleviation of severe male-factor infertility. Nowadays ICSI can be considered as an infertility treatment, providing similar results in male infertility as conventional IVF in female-factor or idiopathic infertility. The ICSI treatment involves several related steps: selection of patients for ICSI, ovarian stimulation and oocyte handling, evaluation and preparation of spermatozoa, the ICSI procedure itself, oocyte damage and pronucleus formation after ICSI, embryo development and replacement and cryopreservation of excess embryos. The audit of IVF and ICSI results is hampered by the way these data are registered in different countries and different centers. A correct and reliable analysis is possible in the United Kingdom; the UK data bank was used to study the factors influencing the outcome of IVF--especially the female age has a determining role. Infertility treatments have induced a sharp increase in the number of multiple pregnancies. Reducing the number of multiple gestations should be considered as a future major challenge for all infertility centers. Since its introduction in 1991 questions have been raised concerning the safety of ICSI, a novel and efficient assisted fertilization procedure. A careful follow-up of the ICSI pregnancies and children is therefore indicated. At the VUB this prospective follow-up of genetic counseling, the possibility of prenatal diagnosis, the problems during pregnancy, the occurrence of (major) congenital malformations as well as a further medical and psychomotor follow-up. The results of 1437 fetal karyotypes indicate that in comparison with a control group there is after ICSI a slight but significant increase of sex chromosomal aneuploidies and de-novo structural aberrations. The percentage of ICSI children (n = 2840) with major congenital malformations was similar to the malformation rate in children from conventional IVF (n = 2955) or natural conception. This prospective follow-up study should be continued much longer--if possible until adulthood to assess the fertility of these children.

Female↗
PubMed1996

Normal pregnancies resulting from testicular sperm extraction and intracytoplasmic sperm injection for azoospermia due to maturation arrest.

OBJECTIVE: To see whether testicular sperm extraction could be used to perform intracytoplasmic sperm injection (ICSI) for men with nonobstructive azoospermia caused by maturation arrest. DESIGN: Uncontrolled prospective trial of an attempt to find occasional elongated spermatids or spermatozoa in testes of azoospermic patients with maturation arrest and to use these haploid cells for ICSI. SETTING: European university-based center for reproductive medicine and private American community hospital. PATIENTS: Thirty-eight azoospermic males without obstruction and with biopsy-documented maturation arrest, seven of whom elected, with their wives, to undergo scrotal exploration and testicular sperm extraction with ICSI in an attempt to become pregnant. INTERVENTIONS: Histologic evaluation of spermatid development in 38 patients with azoospermic maturation arrest. Testicular sperm extraction with ICSI in seven random volunteers from this group. MAIN OUTCOME MEASURES: Presence or absence of mature spermatids in the testis biopsy specimen of patients with azoospermic maturation arrest. Fertilization, cleavage, and pregnancy after testicular sperm extraction and ICSI in patients with azoospermic maturation arrest. RESULTS: All seven patients with azoospermic maturation arrest had occasional sperm found with testicular sperm extraction. Five had sufficient numbers (between 6 and 30) for ICSI, and those five had ETs. In four, the partners became pregnant. In all 38 patients examined, the maturation defect was in meiosis rather than in spermiogenesis. CONCLUSION: Nonobstructive azoospermia caused by maturation arrest may be treated with testicular sperm extraction with ICSI apparently as successfully as Sertoli cell only.

Cellular Senescence↗
PubMed1994

The influence of pentoxifylline on motility and viability of spermatozoa from normozoospermic semen samples.

In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.

Automation↗
PubMed1992

Cryopreservation of human embryos.

This chapter describes general cryobiological principles and the different methods for cryopreservation of supernumerary human embryos obtained after several procedures for medically assisted procreation. Different factors that influence the performance of freezing and thawing of human embryos are reviewed: the data from international and national surveys of results, the cryopreservation procedures, the stages of embryonic development, the morphological appearance of the cryopreserved embryos, the numbers of embryos transferred, the storage times of embryos in liquid nitrogen, the ovarian stimulation protocols in the IVF cycle and the replacement cycles of cryopreserved embryos. Cryopreservation of embryos circumvents the difficult problem of synchrony between the ovarian cycles of donor and acceptor patients in an oocyte donation programme.

Blastocyst↗
PubMed1990

Regulation of maternal thyroid during pregnancy.

A prospective study was undertaken in 606 healthy women during pregnancy to evaluate the changes occurring in maternal thyroid economy as a result of 1) the increased thyroid hormone-binding capacity of serum, 2) the effects of increased levels of hCG on TSH and on the thyroid, and 3) a marginally low iodine intake in the population (50-75 micrograms/day). Four main features were observed. First, thyroidal activity adjusted to the marked increase in serum T4-binding globulin: pregnancy was accompanied by an overall reduction in the T4/T4-binding globulin ratio, with lower free T4 and T3 levels, although in most cases free hormone levels remained within the normal range. The adjustment of thyroidal output of T4 and T3 did not occur similarly in all subjects. In approximately one third of the women, there was relative hypothyroxinemia, higher T3/T4 ratios (presumably indicating preferential T3 secretion), and higher, although normal, serum TSH concentrations. Second, high hCG levels were associated with thyroid stimulation, both functionally (lower serum TSH) and anatomically (increased thyroid size). The data are consistent with a TSH-like effect of hCG on the thyroid. Hence, regulation of the maternal thyroid is complex, resulting from both elevated hCG (mainly in the first half of gestation) and increasing TSH (mainly in the second half of gestation). Third, a significant increase in serum thyroglobulin levels was observed throughout gestation, especially during the last trimester. Fourth, increased thyroid volume was common, and goiter formation not uncommon (goiter was found in 9% of women at delivery). In conclusion, the alterations in maternal thyroid function during gestation are intricate and far from fully understood. In areas of marginally low iodine intake, gestation is associated in a significant number of women with relative hypothyroxinemia, increased thyroglobulin, and enlarged thyroid.

Chorionic Gonadotropin↗