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R Felberbaum

Publications and source records attributed to R Felberbaum.

14 recordsLinked to original sources
PubMed1998

New approaches to ovarian stimulation.

Suppression of endogenous hormone production by gonadotrophin-releasing hormone (GnRH) agonists followed by controlled ovarian hyperstimulation (COH) with human gonadotrophins, especially the so-called 'long protocol' has developed from second-line into first-line therapy. Due to this attitude premature luteinization can be safely avoided, enhancing therapeutic efficacy. Recombinant preparations of human follicle stimulating hormone (FSH) have been proven to be effective within COH according to the long protocol. The high purity of these compounds may have clinical advantages. GnRH antagonists could be successfully introduced in COH protocols. Also, daily injections in the midcycle phase according to the 'Lübeck protocol', as single or only dual administrations around day 9 seem to abolish any premature LH rises. Due to their different pharmacological mode of action, based on a classic competitive receptor blockage GnRH antagonists avoid any flare-up period and allow ovarian stimulation to start within the spontaneous cycle. Pregnancy rates are comparable to those after long protocol stimulation. Combination of softer stimulation regimes like clomiphene citrate and low dose HMG with midcycle administration of GnRH antagonists may be the way to a cheap, safe and efficient ovarian stimulation. It seems to be high time for modest forms of ovarian stimulation, lowering burden and risk for our patients.

Female↗
PubMed1996

Hormone profiles under ovarian stimulation with human menopausal gonadotropin (hMG) and concomitant administration of the gonadotropin releasing hormone (GnRH)-antagonist Cetrorelix at different dosages.

PURPOSE: The premature LH surge in ART programs seems to be avoided by daily administration of the GnRH-antagonist Cetrorelix during the midcycle phase in controlled ovarian hyperstimulation with hMG. The dosage necessary for sufficient suppression of the pituitary gland is not yet defined. METHODS: To elucidate this question three daily dosages (3, 1, 0.5 mg) were administered and the hormone profiles obtained as well as the number of oocytes retrieved, the fertilization rate, and the consumption of HMG were compared. RESULTS: No premature LH surge could be observed at any of the three dosages administered. Both gonadotropins were deeply suppressed. The fertilization rates of the oocytes obtained were 45.3% in the 3-mg group, 53.1% in the 1-mg group, and 67.7% in the 0.5-mg group. The average uses of hMG ampoules were 30 in the 3-mg group, 27 in the 1-mg group, and 26 in the 0.5-mg group. CONCLUSIONS: Cetrolix, 0.5 mg/day, administered during the midcycle phase of controlled ovarian hyperstimulation with hMG is enough to prevent completely the premature LH surge. Perhaps even lower dosages would be sufficient. Regarding fertilization rates and use of hMG, the lower dosage seems to be the most favorable.

Adolescent↗
PubMed1996

Small-diameter laparoscopy (SDL) using a microlaparoscope.

PURPOSE: To determine the ability of new sub-2.0-mm-diameter microlaparoscopes to be used for diagnostic laparoscopy, 28 small-diameter laparoscopies (SDL) were performed during a 4-month-period. METHODS: These cases were performed under general anesthesia, with immediate follow-up confirmation with conventional laparoscopic equipment. An additional 13 SDL procedures were performed under analgosedation plus local anesthesia and were well tolerated by the patients. RESULTS: For the cases performed with conventional laparoscopic control, the visualization results were comparable in 27 of 28 procedures. In the nongeneral anesthesia SDL group, patients were highly satisfied and reported less post-procedural discomfort and minimal scar formation due to the smaller access ports. In this study, two types of microlaparoscopes were used. CONCLUSIONS: While both were adequate, the newer high-resolution microlaparoscope delivered an image much more similar to that which conventional laparoscopy and required little or no change in technique in order to obtain images. With the advent of this new endoscope technology with optics performance comparable to that of conventional laparoscopes, SDL has demonstrated to be a useful procedure for certain clinical indications.

Evaluation Studies as Topic↗
PubMed1996

[Significance of tumor necrosis factor alpha (TNF-alpha) in endometriosis].

Macrophage-derived substances such as cytokines and growth promoting factors are known to be present in the peritoneal fluid of women with endometriosis. Active endometriosis of the peritoneum is characterised by hypervascularization and neoangiogenesis. TNF-alpha is a pleiotropic cytokine also involved in angiogenesis and immunoregulation. Our question was to determine whether there are differences in the peritoneal TNF-alpha concentrations in women with various degrees of active and inactive endometriosis. We found that TNF-alpha concentrations were higher in the peritoneal fluid of women with endometriosis than in the peritoneal fluid of those without. TNF-alpha concentrations were higher in cases of active endometriosis than in cases of inactive endometriosis. The highest concentrations could be detected in women with severe endometriosis (stage III and IV rAFS).

Adult↗
PubMed1996

[Pregnancy and extreme myomatous uterus--conservative management].

The management of a pregnancy complicated by uterus myomatosus remains being controversially discussed. Myomectomy early in pregnancy is opposed by exspectative management with myomectomy subsequent to the post partum period. Therapeutic abortion and exstirpation of the gravid uterus represent only hypothetical but not reasonable alternatives. Complications like ureteral obstruction, sepsis, and torsion of the uterus with subperimetrial bleeding as a cause of fever of unknown origin may occur. Rapid growth of a fibromatous uterus in pregnancy may call for a biopsy. Two cases are presented to demonstrate that with intensive pregnancy surveillance exspectative management is justified and may lead to successful confinement of the pregnancy.

Adult↗
PubMed1996

[Risks of expectant management of extrauterine pregnancies with low HCG titers and absent clinical symptoms].

We report on 4 cases of ectopic pregnancy with low HCG-levels and lack of clinical symptoms, in which expectant management was performed. Advantages and disadvantages of the procedure are discussed. While one can find a variety of therapeutical concepts in the literature such as conservative medical treatment alone or in combination with laparoscopy or expectant management, we dispose to prefer a fertilization providing gentle operative laparoscopic assessment as the treatment of choice in all cases of ectopic pregnancy. In all 4 cases operative laparoscopy had to be performed after an interval of expectance when the patients displayed sudden severe clinical symptoms.

Adult↗
PubMed1995

Morphology in intracytoplasmic sperm injection: preliminary results.

PURPOSE: Direct intracytoplasmic sperm injection (ICSI) is a successful treatment of severe male subfertility. Conventional in vitro fertilization shows poor pregnancy rates especially in cases of severe teratozoospermia. The objective was to determine if severe morphological defects of spermatozoa in oligoasthenoteratozoospermia (OAT) have any impact on the fertilization process in ICSI and if there are any specific morphological characteristics in nonfertilized oocytes after the ICSI procedure. METHODS: Ejaculates and nonfertilized oocytes were investigated by electron microscopy. CONCLUSIONS: The lack of intracytoplasmic sperm-oocyte interaction, not severe sperm defects, displays the most critical role in the fertilization process. Clinical data with fertilization rates of 66% and pregnancy rates of 23.3% confirm the fertilization capacity of severely

Acrosome↗
PubMed1995

[Diagnostic microlaparoscopies with 2 mm optics].

Within a period of 5 months a serious of 42 small diameter laparoscopies (2 mm) (SDL) were performed with a modified technical approach. 28 (SDL). Procedures were done under general anaesthesia and the findings were controlled by concurrent conventional laparoscopy. In 26 out of 28 patients we could confirm the SDL diagnosis. 14 patients had SDL in analgosedation. Optical information gained by SDL was sufficient and, as experience in handling the system increased, also competitive. The procedures performed in analgosedation were tolerated and highly appreciated (reduced incisional pains, reduced complaints due to pneumoperitoneum). SDL procedures seem to have possible indications in gynaecology.

Adult↗
PubMed1995

Development and applications of luteinizing hormone-releasing hormone antagonists in the treatment of infertility: an overview.

Luteinizing hormone-releasing hormone (LHRH) plays a crucial role in controlling the ovarian cycle in women. By modification of the molecular structure of this decapeptide, analogues were synthesized with agonistic or antagonistic effects on the gonadotrophic cells of the anterior pituitary gland. The agonists, after an initial stimulatory effect ('flare up'), lead to desensitization of the gonadotrophic cells and a reduction in the number of LHRH receptors on the cell membrane ('down-regulation'), while the antagonists produce an immediate effect by competitive blockade of the LHRH receptors. After administration of LHRH antagonists, the serum levels of FSH and LH decrease within hours. Nevertheless, the adenohypophysis maintains its responsiveness to an LHRH stimulus ('pituitary response') after pretreatment with an antagonist. This different pharmacological mechanism of LHRH antagonists makes possible new approaches to ovarian stimulation and to the therapy of sex steroid dependent diseases. The premature LH surge, the main cause of cancellation during induction of superovulation in assisted reproduction technology (ART) programmes, can be abolished by short term application of an LHRH antagonist associated with a reduced human menopausal gonadotrophin (HMG) requirement for ovarian stimulation. A future approach to ART might be based on the combination of pretreatment with an LHRH antagonist and ovulation induction by native LHRH or an agonist. The severe side effects encountered with early LHRH antagonists, such as anaphylactoid reactions due to histamine release, are almost completely eliminated in modern antagonists, especially Cetrorelix which is presently used clinically in controlled phase II clinical studies.

Adult↗
PubMed1995

[GnRH antagonists in gynecology: initial results within the scope of controlled ovarian hyperstimulation].

OBJECTIVE: Applicability of the GnRH-antagonist Cetrorelix within controlled ovarian hyperstimulation (COH) to avoid the premature LH-surge should be examined. METHODS: 35 patients suffering from tubal infertility were stimulated for In Vitro Fertilization (IVF) by human menopausal gonadotrophins (HMG) and concomitant administration of Cetrorelix in different dosages (3 mg, 1 mg, 0,5 mg). RESULTS: No premature LH-surge could be observed. CONCLUSIONS: Short term administration of the GnGR-antagonists avoids the occurrence of a premature LH-surge.

Adult↗
PubMed1995

[Morphology in intracytoplasmic sperm injection].

OBJECTIVE: Was to determine if severe morphological defects of spermatozoa in Oligo-Astheno-Teratozoospermia (OAT) have any impact on the fertilization process in intracytoplasmic sperm injection (ICSI) and, if there are any specific morphological characteristics of unfertilized oocytes after the ICSI procedure. METHODS: Ejaculates of males with severe subfertility and unfertilized oocytes after the ICSI procedure were investigated by transmissionelectronmicroscopy. RESULTS: ICSI provided a fertilization rate of 66% in cases of severe defective spermatozoa. The ultrastructure revealed severe head and neck alterations in particular. The ultrastructure of the unfertilized oocyte displayed mostly no signs of activation and lack of decondensation of sperm chromatin. CONCLUSIONS: Our findings support the hypothesis that not severe sperm defects but the lack of intracytoplasmic sperm-oocyte interaction displays the most critical role in the fertilization process in intracytoplasmic sperm injection.

Female↗
PubMed1995

New approaches to male infertility: IVF and microinjection.

The male factor represents a major problem in the treatment of infertility. New methods of assisted fertilization such as partial zona dissection (PZD), subzonal sperm injection (SUZI) and intracytoplasmic sperm injection (ICSI) are described and discussed in terms of their potential benefits for infertility treatment in comparison to classical in-vitro fertilization (IVF) and intra-uterine insemination (IUI).

Fertilization in Vitro↗