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Biomedical subjects

O Bauer

Publications and source records attributed to O Bauer.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Ovarian stimulation with various FSH/LH concentrations in an in vitro fertilization program].

Various stimulation regimes have been tried to induce multiple follicular development for in-vitro fertilisation and embryo transfer. Human menopausal gonadotrophins have been widely used to induce follicular growth. To evaluate the role of the FSH: LH-ratio and the importance of LH concentrations, the results of a randomised assessor-blind group comparative efficacy and safety study are described. The effects of preparations, comprising FSH: LH-ratio of 3:1 and FSH: LH-ratio of 1:1 respectively, in stimulation of the ovaries for in-vitro fertilisation in infertile women are compared. Patients under 38 years of age with regular menstrual cycle (27 +/- 3 days and 32 +/- 3 days) are included. Sperm parameters have to be in normal range, according to WHO criteria. Follicular and luteal hormone parameters, ultrasound measurements, oocyte quality, fertilisation, cleavage and pregnancy rates are reported. The outcome of in-vitro fertilisation after the administration of preparations containing different ratios of FSH:LH leads to comparable results. However, the rate of ovarian hyperstimulation syndrome and the abortion rate after embryo transfer seems to be lower in patients stimulated with FSH dominant gonadotrophins.

Dose-Response Relationship, Drug↗
PubMed1994

[Suppression of endogenous LH increase in ovarian stimulation with the GnRH antagonist Cetrorelix].

Surges of LH in serum, which result in luteinization, but occur prematurely with respect to the diameter of the leading follicle, frustrate attemps to induce multiple follicular maturation for in-vitro fertilisation in a number of women. We examined the possibility of blocking premature LH-surges by the administration of Cetrorelix, a potent antagonist of gonadotrophin releasing hormone. Twenty patients, who had repeatedly shown premature LH surges, were treated with human menopausal gonadotrophins from the 2nd day onwards. From the 7th day until the induction of ovulation by HCG, the GNRH-antagonist Cetrorelix was given daily. HCG was injected when the dominant follicle had reached the diameter of at least 18 mm and oestradiol levels were above 300 pg for each follicle and more than 15 mm. Oocyte collection was performed 36 hours later by transvaginal ultrasound puncture, followed by IVF and embryo transfer. The hormone profiles of these patients and the results of in-vitro fertilisation and embryo transfer are discussed. It could be demonstrated in this study, that combined treatment with gonadotrophins and the GNRH-antagonist seems to be a promising method for ovarian stimulation in patients, who frequently exhibit premature LH discharges and therefore fail to complete treatment.

Adult↗
PubMed1994

Transcervical tubal transfer of gametes and embryos.

The benefit of intrafallopian transfer techniques is still disputable in assisted reproductive techniques. On this background, alternatives to laparoscopic transfer procedures are in development. Current transcervical intrafallopian transfers of gametes and embryos are lacking success and reproducibility of results. New developments in catheter techniques and optical systems are offering new concepts for more successful transcervical approaches and preparing the basis for truly prospective studies.

Embryo Transfer↗
PubMed1993

[In vitro fertilization. Prognostic factors].

Multiple factors influence the outcome of in vitro fertilisation and embryo transfer (IVF-ET). In our prospective study different factors have been subject of examination concerning their effect on the outcome of in vitro fertilisation and embryo transfer. 1237 couples undergoing 1675 consecutive treatment cycles between 1.1.1990-31.12.1991 were included in this study. Prior to treatment, couples were divided into "good" and "poor" prognosis groups. Cycles were prospectively labelled as carrying a potentially "poor prognosis", if one or more of the following factors were noted: 1) female age > 35; 2) an existence of male factor; 3) couples with more than 3 previous unsuccessful treatment cycles. Couples with none of these factors were assigned to the "good" prognosis group. The pregnancy rate per cycle in the "poor" prognosis group was 5.96%, compared with 17.92% per cycle in the "good" prognosis group (p < 0.001). The most important factors determining pregnancy rates were female age and male factor, and we observed that the rate of pregnancy declined after the third treatment cycle. An explanation may be seen in lower fertilisation rates after the age of 35 and cases of poor semen quality. Both will result in poor embryo quality.

Adult↗
PubMed1993

[Folic acid supply in pregnancy--results of a prospective longitudinal study].

After discussing the problem of folic acid requirements and supply during pregnancy, the results of a longitudinal study on 162 pregnant women are presented. By measuring biochemical and morphological changes in two subgroups (non-substituted vs unspecifically substituted), the necessity of a substitution with folic acid is discussed, as there might be additional requirements for the pregnant and the foetal organism. Concentrations of folic acid in the maternal plasma and in the erythrocytes as well as the segmentation rate and hypersegmentation of the granulocytes show a clear decrease in pregnancy. At the same time there was a significant difference between the subjects substituted and not substituted; the foetus and newborn levels were much higher than their mothers' concentrations. Moreover, there was a correlation between red cells folic acid levels in the last trimester and duration and outcome of pregnancy. These results indicate a substitution with folic acid for certain populations in pregnancy, which are highlighted.

Adolescent↗
PubMed1992

Indications and outcomes of assisted reproduction.

Since 1978 many healthy children have been born after in vitro fertilization and embryo transfer, fulfilling the wishes of many previously childless couples. In vitro fertilization and subsequently developed methods (GIFT, intratubal embryo transfer) have contributed to progress in the diagnosis and treatment of unwanted childlessness. Furthermore these techniques have improved knowledge of ovarian function, fertilization and early embryo development.

Embryo Transfer↗
PubMed1992

Indications for in-vitro fertilization and results.

During the last few years, many healthy children have been born after in vitro fertilization and embryo transfer, fulfilling the wish for a child for many couples who had often nearly given up hope. Because of in vitro fertilization and other related methods developed subsequently (gamete intra-Fallopian transfer, intratubal embryo transfer), progress in the diagnosis and treatment of involuntary childlessness took place and has helped many patients. Furthermore, by dealing with these methods, new knowledge about ovarian function, fertilization and early embryonic development could be gained. This has also led to better treatment of childless couples. Despite the broad diagnostic and therapeutic possibilities of reproductive medicine, its limits must also be taken into account. These limitations have been recognized early by physicians and scientists dealing with this subject and also by society. Guidelines and laws have been drawn up which now give a clear framework.

Embryo Transfer↗
PubMed1992

Transcervical access and intra-luminal imaging of the fallopian tube in the non-anaesthetized patient; preliminary results using a new technique for fallopian access.

A study was performed to evaluate a new transcervical, Fallopian tube access system for use in falloposcopy procedures without the need for conventional hysteroscopy or uterine distension. Visualization was accomplished by the use of a 0.5 mm falloposcope which was delivered to the Fallopian tube by a new linear everting catheter. The linear everting catheter allows access to the Fallopian tube by means of a flexible, tubular rolling membrane which can safely negotiate the tortuous anatomy from the ostium to the ampulla. Concurrent laparoscopy was performed solely for supervision purposes and not for tubal manipulations in 13 Fallopian tube access procedures in 10 patients. The ostia were visualized in 12 cases and the Fallopian tube was accessed in all 12 without complications. As a precursor for future gamete and embryo transfer procedures, intra-tubal insemination was performed by visualizing the ostia, accessing the Fallopian tubes, and obtaining successful isthmic-ampullary, intra-luminal images.

Catheterization↗
PubMed1992

Chlorinated hydrocarbon content of fetal and maternal body tissues and fluids in full term pregnant women: a comparison of Germany versus Tanzania.

Chlorinated hydrocarbons are distributed worldwide and due to their lipophilic properties and chemical stability they accumulate in the foodchain. The concentrations of 19 different chlorinated hydrocarbons (hexachlorohexane (HCH), DDT and various metabolites and nine different polychlorinated phenyl (PCB) congeners were detected in various body tissues and fluids (maternal and fetal serum, adipose tissue, placenta, amniotic fluid) of full term pregnant women from Germany and Tanzania. Great variation of total toxin burden and toxin distribution within the different body compartments was found. This was in part due to local differences of exposure to some of the chlorinated hydrocarbons. Comparing samples from Germany and Tanzania, typical distribution patterns reflected the specific economic situation of the two countries with a high burden of insecticides (DDT and Dieldrin) in the agricultural country and high levels of constituents of industrial products (hexachlorobenzene (HCB) and PCBs) in Germany. Different chlorinated hydrocarbons seem to show different distribution patterns in body tissues, probably due to their chemical structure, the lipid content of the compartment and the overall toxin burden of the individual. A 10 to 100 fold accumulation of chlorinated hydrocarbons was observed in maternal adipose tissue compared with the other compartments. The concentrations of certain toxins in fetal cord serum and placenta were higher than in maternal serum.

Adipose Tissue↗
PubMed1991

Transvaginal intratubal embryo transfer: a new treatment of male infertility.

Intratubal embryo transfer is a new method in the treatment of human infertility. Following transvaginal sonographic oocyte retrieval, in-vitro fertilization (IVF) is performed and embryos are transferred into the Fallopian tube transvaginally. In comparison with gamete intra-Fallopian transfer (GIFT), fertilization under in vitro conditions offers the advantage that the success of the fertilization process can be examined. Therefore, this method can give important diagnostic information, especially in cases of poor sperm quality or unexplained infertility. After fertilization in vitro and transfer into the tube, embryonic development occurs in the physiological milieu of the oviduct. Transvaginal intratubal embryo transfer was performed in 95 patients with male factor infertility. In 29 cases (31%), a pregnancy was achieved. One abortion, but no ectopic pregnancy was observed. This method combines the advantages of IVF and GIFT and offers a successful procedure for the treatment of infertility.

Embryo Transfer↗
PubMed1991

Multicenter evaluation of new enzyme-linked immunoassays of follitropin and lutropin in serum or plasma.

Results from a multicenter evaluation of two new enzyme-linked immunosorbent assays [Enzymun-Test for follitropin (FSH) and lutropin (LH)] are presented and compared with results from 11 other commercial immunoassays, radioactive as well as nonradioactive. Enzymun-Test FSH and LH assays are suitable for automated systems and manual applications. The tests were reproducible (CV less than 5%), highly specific, and sensitive enough (less than 0.5 int. unit/L) to measure the hormones directly in almost all patients' samples, except for LH measurements in prepubertal children. We did not find interference by heterophilic antibodies or other factors. A comparison of assays for FSH found very good agreement among all modern two-site assays; competitive immunoassays almost invariably yielded systematically lower results for FSH, probably because of the heterogeneity of the International Reference Preparation (2nd IRP FSH, 78/549). For LH also we found good agreement, with no systematic differences among the various reagents. Guidelines for reference values with the new reagents are given.

Adult↗
PubMed1990

Preliminary results on transvaginal tubal embryo stage transfer (TV-TEST) without ultrasound guidance.

IVF procedures have been increasingly used in male subfertility for both therapeutic and diagnostic purposes. As we assume a positive influence of the tubal milieu on the early embryonal development, any therapy should aim at intratubal embryo transfer. In this respect, only invasive techniques such as laparoscopy or laparotomy have been available hitherto (Asch et al., 1986; Balmaceda et al., 1988; Diedrich et al., 1989). Transvaginal intra-tubal embryo stage transfer (TV-TEST) was performed in 15 patients. After stimulation with clomiphene/HMG, HMG or GnRHA/HMG, patients with a follicle size of 18 mm were given 10000 IU HCG. Thirty six hours later, the transvaginal oocyte retrieval was performed without anaesthesia. Altogether, 109 oocytes were recovered. A fertilization rate of 30.3% yielded 33 embryos. Forty-eight hours after oocyte retrieval, the TV-TEST was performed without anaesthesia, in the course of which a maximum of three embryos in the 2- to 8-cell stage were transferred into one tube. Six of these patients are now pregnant.

Catheterization↗
PubMed1989

[Sterilization failures following fibrectomy].

Four of 272 patients with bilateral fimbriectomy became pregnant. In each of the four cases the distal end of the Fallopian tubes was closed but a tubo-peritoneal fistula could be observed in the antimesenterial part of the tube - immediately proximal of the former ligatures. These failures of sterilization were all found in a group of 16 patients, in which VICRYL 2/0 was used for ligation after resection of the fimbriated end. In all the other cases of fimbriectomy Chromcatgut 2/0 was used.

Adult↗
PubMed1988

Pelvic assessment and cephalo-pelvic disproportion in Central Tanzania.

Among 201 primigravidae, pelvic assessment was analyzed prospectively during the third trimester to detect patients likely to suffer from cephalo-pelvic disproportion (CPD). If the sacral promontory (SP) was reached by the index finger (9.0-9.5 cm true conjugate) the pelvis was regarded as "suspect". All patients who later developed CPD were in this group. Of the screened primigravidas, 22% were advised to deliver in the hospital. Pelvic assessment is an important screening tool during antenatal care to detect high-risk primigravidas.

Cesarean Section↗
PubMed1978

[Primary shape change of platelets in vitro (author's transl)].

Studies with interference contrast microscopy reveal that platelets undergo a typical shape change within 30--60' after venepuncture, i.e. swelling, formation of large tentacles, tiny protrusions and vesicles at the platelet surface. This "shape change" can be observed in citrated blood and PRP, heparinized blood and EDTA-blood as well. It is enhanced by low incubation temperatures (4 degrees C, 10 degrees C) and delayed at 37 degrees C as compared with room temperature. An increased number of primarily shape changed platelets is found if platelets are strongly mechanically irritated at blood sampling. The shape change is partly reversible in vitro, it is completely or almost completely reversible in vivo. Some antiaggregating agents inhibit the in vitro shape change at varying degrees (Bencyclan, SH 869 greater than ASA greater than D-Propranolol). The shape change is partly inhibited after oral or i.v. administration of ASA. A typical transformation of platelets into "spheric" forms can be observed following the addition of Bencyclan, SH 869 and D-Propranolol to PRP in vitro. The spontaneous "primary shape change" which occurs in PRP or blood after blood sampling is probably different from the secondary ADP-induced shape change. The primary shape change may influence the results of different platelet function and aggregating tests. The shape change kinetics of "healthy" subjects and patients with Hodgkin's disease differ significantly. The described method may gain more clinical interest in the future.

Aspirin↗