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Featured researches published by K. Fiedler.
Urologia Internationalis | 2003
J. Ullrich Schwarzer; K. Fiedler; Irene von Hertwig; G. Krüsmann; W. Würfel; Manfred Schleyer; Bärbel Mühlen; Ulrich Pickl; Dieter Löchner-Ernst
Introduction: Male infertility caused by azoospermia due to non-reconstructable obstruction or non-obstructive azoospermia can be treated by microsurgical epididymal aspiration (MESA) or testicular sperm extraction (TESE) followed by an intracytoplasmatic spermatozoa injection (ICSI). Material and Methods: From 9/93 to 6/01, we carried out 1,025 ICSI procedures with aspirated epididymal or testicular sperms in 684 cases. 163 ICSI cycles were performed with epididymal sperms and 862 ICSI cycles with testicular sperms or spermatids. The TESE was carried out by open biopsy, frequently in a multilocular technique. The aspirated spermatozoas were used after cryopreservation (frozen) or immediately after aspiration (fresh). Results: 538 patients had obstructive azoospermia or ejaculation failure. In 487 cases the underlying cause of azoospermia was an impaired spermatogenesis, following maldescensus testis, chemotherapy, radiotherapy, or caused by Sertoli-cell-only syndrome, a genetic disorder or an unknown etiology. The transfer rates, pregnancy rates and birth rates per ICSI cycle showed no statistically significant differences between testicular and epididymal sperms in the cases of seminal obstruction (28% average birth rates in both cases). However, highly significant was the difference in birth rates with regard to the underlying cause of infertility. In contrast, in treating non-obstructive azoospermia we observed a birth rate of 19% per cycle. In all patient groups the birth rate with fresh spermatozoas did not differ from those with cryopreserved spermatozoa. 40% of patients after multilocular TESE showed clinical signs of testicular lesion. Conclusion: The underlying cause of azoospermia is the most important factor for the outcome of ICSI using epididymal and testicular sperms. In cases of non-obstructive azoospermia, the pregnancy rate is low compared with the results in cases of obstructive azoospermia. There is no difference between fresh and cryopreserved sperms. TESE with ICSI is the most efficient treatment of azoospermia caused by hypergonadotropic hypogonadism. The morbidity of the TESE procedure is highly relevant and must be considered if this technique is indicated.
Asian Journal of Andrology | 2013
J. Ullrich Schwarzer; Heiko Steinfatt; Manfred Schleyer; Frank M. Köhn; K. Fiedler; Irene von Hertwig; G. Krüsmann; Wolfgang Würfel
In 220 consecutive patients with non-obstructive azoospermia, sperm retrieval was attempted by a combination of conventional and microdissection testicular sperm extraction (TESE). For sperm retrieval, 2-3 conventional biopsies were performed followed by a microdissection TESE in cases of negative conventional biopsies. During the surgery, the vasculature of the testis was assessed using the operative microscope, and the location of positive biopsies was registered in relation to the blood supply. The overall sperm retrieval rate was 58.2%. From the initial conventional biopsies, sperm could be retrieved in 46.8% of the patients. With microdissection TESE, sperm could be retrieved from an additional 11.4% of the patients. The further use of microdissection TESE improved the sperm retrieval rate significantly (P=0.017). No significant accumulation of positive biopsies was found towards the rete testis or the main testicular vessels.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1992
W. Würfel; Hertraut Haas-Andela; G. Krüsmann; Maria Rothenaicher; Peter Hirsch; Henryk K. Kwapisz; Joachim Haas; Inge Högemann; K. Fiedler
We report on the outcome of 82 amniocenteses (AC) carried out during pregnancies after in vitro fertilization (IVF) from 1-1-1985 to 31-12-1989. The main indication for amniocentesis was a maternal age of greater than or equal to 35 years. In 48 cases, we found an anterior placenta and assumed that this was related to the position in which the uterine embryo transfer was performed. In six pregnancies, we found an abnormal karyotype, including two cases of trisomy 21; the two couples decided for abortion. Four aberrations in the fetal karyotypes were also present in either the mother or the father, the resulting children are healthy. The further course of pregnancies after IVF and AC was characterized by a higher incidence of toxemia, uterine bleeding before the 28th week of gestation, abruptio placentae, and premature deliveries, when compared to the course of pregnancies after spontaneous conception. We believe that these occurrences were not caused by AC, as the incidence was higher in all our pregnancies after IVF (without AC) and has also been reported in pregnancies after ovarian hyperstimulation without IVF. Therefore, we see no reason to renounce AC after IVF. However, the special risks inherent in pregnancies after IVF must always be discussed with the couple.
Andrologia | 2016
J. U. Schwarzer; Heiko Steinfatt; Manfred Schleyer; Frank M. Köhn; K. Fiedler; I. von Hertwig; G. Krüsmann; W. Würfel
Nonobstructive azoospermia is caused in up to 10% by microdeletions of the Y chromosome in the azoospermia factor (AZF) region, which is divided into three nonoverlapping areas (AZFa, AZFb and AZFc). In 25 male patients with AZF microdeletions, the results of two different techniques for surgical sperm retrieval (SR), conventional multilocular TESE and microdissection TESE, were studied retrospectively over a period of 19 years. Conventional multilocular TESE was carried out in 11 patients and microdissection TESE in 14 patients. Successful SR was possible only in patients with isolated AZFc microdeletions, so only the 20 patients with AZFc microdeletions alone were taken into account for the comparison of the both operative techniques. The sperm detection rate for conventional multilocular TESE was 25%, the sperm detection for microdissection TESE was significantly higher with 67%. In all patients, a histological examination of the testicular tissue was carried out, which showed a mixed picture, but Sertoli‐cell‐only syndrome in most cases. FSH was no prognostic marker for successful SR. In two of six couples performing an intracytoplasmic sperm injection until now, a pregnancy occurred.
Gynakologisch-geburtshilfliche Rundschau | 1998
W. Würfel; G. Krüsmann; K. Fiedler; Manfred Schleyer; Peter Adolf Mäurer; Claus Waldenmaier; Ullrich Schwarzer
: We report on our experiences with intracytoplasmic injection (ICSI) of epididymal and testicular spermatozoa (MESA, TESE) from azoospermic men whose wives had previously failed to become pregnant after several cycles of artificial insemination by donor (AID); because we do not perform AID treatment in our clinic, all these treatments were carried out in other fertility centers as well as the female diagnostic of sterility. In 3 husbands we could not find any testicular spermatozoa or spermatids, leaving 15 women under treatment. Of these 15 women, 9 became pregnant. This accounts for a pregnancy rate per patient of 60%. We believe that functional defects of the oocytes and somatizing psychological problems concerning AID are predominantly responsible for these results and that both problems can be overcome by ICSI. Besides, these results demonstrate that ICSI/MESA and ICSI/TESE are effective approaches in the treatment of azoospermic men and that using cryopreserved spermatozoa is not disadvantageous in the outcome of ICSI.
Gynakologisch-geburtshilfliche Rundschau | 1996
W. Würfel; G. Krüsmann; K. Fiedler; Irene von Hertwig; Ulrich Schwarzer
For the first time we report on an intact and ongoing triplet pregnancy after intracytoplasmatic sperm injection of cryopreserved testicular sperm. Indication was azoospermia due to hypergonadotropic hypogonadism. The patient conceived in the third treatment cycle after 25 treatment cycles with donor sperm that had been carried out without success in two other treatment centers.
Gynakologisch-geburtshilfliche Rundschau | 1991
K. Fiedler; G. Krüsmann; W. Würfel
Die pelviskopische Sanierung der Extrauteringraviditat hat sich in den letzten Jahren zunehmend als alternative Methode zu dem klassischen Verfahren der Laparotomie entwickelt. Alle bisher zu diesem Thema veroffentlichten Untersuchungen befassen sich allerdings ausnahmslos mit Tubarias nach Spontankonzeption. Da bei der IVF-Patientin aufgrund der vorausgegangenen operativen Eingriffe haufig mit einem wesentlich komplizierterem Situs zu rechnen ist, und hier in etwa 5% der eingetretenen Schwangerschaften mit einer Extrauteringraviditat zu rechnen ist, haben wir untersucht, inwieweit sich diese Operationstechnik auch fur die Patientin nach IVF-Behandlung eignet bzw. welche Unterschiede zum Patientenkollektiv mit EUG nach Spontankonzeption bestehen. Im Beobachtungszeitraum von exakt 2 Jahren (1988 bis 1989) wurden insgesamt 34 Patientinnen behandelt.
Human Reproduction | 2010
W. Würfel; Claudia Santjohanser; Kaimo Hirv; Monika Bühl; Osama Meri; Ina Laubert; Irene von Hertwig; K. Fiedler; Jan Krüsmann; G. Krüsmann
European Journal of Medical Research | 2004
K. Fiedler; W. Würfel
Human Reproduction | 1993
K. Fiedler; Dieter Löchner-Ernst; G. Krüsmann; W. Würfel; Manfred Stöhrer