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Dive into the research topics where Willy Hänggi is active.

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Featured researches published by Willy Hänggi.


Fertility and Sterility | 2003

Semen quality of male smokers and nonsmokers in infertile couples

Robert Künzle; Michael D. Mueller; Willy Hänggi; Martin Birkhäuser; Heinz Drescher; Nick A. Bersinger

OBJECTIVE To investigate the effect of cigarette smoking on main sperm variables. DESIGN Cohort study. SETTING Men attending the andrology laboratory in the context of infertility investigation in the couple. PATIENT(S) Eight hundred thirty-nine smokers and 1,266 non-smokers were enrolled; 655 smokers and 1,131 nonsmokers fulfilled the inclusion criteria and were compared. Standard clinical analysis of semen. RESULT(S) Cigarette smoking was associated with a significant decrease in sperm density (-15.3%), total sperm count (-17.5%), total number of motile sperm (-16.6%), and citrate concentration (-22.4%). The percentage of normal forms was significantly reduced in smokers, and sperm vitality, ejaculate volume, and fructose concentration were slightly but nonsignificantly affected. CONCLUSION(S) Cigarette smoking is associated with reduced semen quality.


British Journal of Obstetrics and Gynaecology | 1997

Long term influence of different postmenopausal hormone replacement regimens on serum lipids and lipoprotein(a) : a randomised study

Willy Hänggi; Kurt Lippuner; Walter Riesen; Phillippe Jaeger; Martin Birkhäuser

Objective To assess the influence of three different postmenopausal hormone replacement therapies on levels of serum lipids and lipoprotein(a) [Lp(a)].


Surgical Endoscopy and Other Interventional Techniques | 1999

Three-dimensional laparoscopy. Gadget or progress? A randomized trial on the efficacy of three-dimensional laparoscopy.

Michel D. Mueller; C. Camartin; Ekkehard Dreher; Willy Hänggi

AbstractBackground: This study was designed to compare conventional laparoscopy with three-dimensional (3-D) laparoscopy. Method: Thirty candidates, 20 inexperienced and 10 experienced in operative laparoscopy, executed standardized exercises on a pelvitrainer. The candidates were randomized to two groups. Group A executed the exercises first with the conventional and then with the three-dimensional system. Group B accomplished the exercises in the reverse sequence. At the end of the exercises, the candidates answered specific questions about the two systems. Results: A total of 21 h 6 min 6 sec of laparoscopic exercises were analyzed—10 h 8 min 1 sec with the conventional and 10 h 58 min 5 sec with the three-dimensional system (p= 0.38). Group A required 12 h 26 min 56 sec to perform all the exercises. There was no statistically significant difference from group B, where the candidates needed 8 h 39 min 10 sec (p= 0.14). Neither were there any differences in the number of failed attempts between the two groups. There were also no statistical difference when the results obtained from the candidates without experience in laparoscopy and the participants experienced in operative laparoscopy were analyzed separately. Both the inexperienced and the experienced candidates became tired earlier, had more headaches, and needed extra time to adapt to the 3-D system. Conclusion: When analyzed in a standardized fashion, 3-D laparoscopy does not have any significant advantages over conventional laparoscopy.


Clinical Endocrinology | 1998

Differential impact of conventional oral or transdermal hormone replacement therapy or tibolone on body composition in postmenopausal women

Willy Hänggi; Kurt Lippuner; Philippe Jaeger; Martin Birkhäuser; F. F. Horber

To compare the effects on body composition and body weight of tibolone vs two different sequential oral or transdermal oestrogen‐progestogen hormone replacement therapies versus no therapy.


British Journal of Obstetrics and Gynaecology | 2002

Effects of tibolone and continuous combined hormone replacement therapy on bleeding rates, quality of life and tolerability in postmenopausal women

J. Huber; S. Palacios; L. Berglund; Willy Hänggi; S.M. Sathanandan; S. Christau; Frans A. Helmond

Objective To compare the effects of tibolone and conjugated equine oestrogens continuously combined with medroxyprogesterone acetate on bleeding rates, quality of life (QoL) and tolerability.


Obstetrics & Gynecology | 1997

Pelvimetry by magnetic resonance imaging as a diagnostic tool to evaluate dystocia

Stefan Spörri; Willy Hänggi; Antonio Braghetti; Peter Vock; Henning Schneider

Objective To test the clinical value of magnetic resonance imaging (MRI) pelvimetry for the diagnosis of cephalopelvic disproportion. Methods All deliveries from January 1993 through December 1994 were reviewed to identify 42 nulliparas at term with vertex presentation and cesarean delivery due to dystocia. Complete data were available for 41 women, and subjects were diveded into the following two subgroups, according to clinical data: “cephalopelvic disproportion” (n = 28) and “failure to progress” (n = 13). Ten nulliparous women with uncomplicated vaginal delivery served as controls. Pelvimetry data from postpartum MRI were correlated with fetal and neonatal dimensions to evaluate various criteria for the diagnosis of cephalopelvic disproportion. Results Comparing both the fetal head volume derived from antepartum ultrasound assessment and the neonatal head volume (postpartum measurement) with maternal pelvic capacity determined by MRI, cephalopelvic disproportion (head volume exceeding pelvec capacity) indicated that 25 and 27, respectively, of the 28 women had been clinically diagnosed correctly with cephalopelvic disproportion, corresponding to sensitivities of 89% and 96%, respectively. Feltal head volume was not larger than pelvic capacity in any of the women in the control group. In seven of the 13 women diagnosed as “failure to progress,” the fetal head volume exceeded the pelvic capacity. Conclusion a fetal head volume estimate exceeding MRI measured pelvic capacity is a frequent finding in nulliparas with cesarean birth due to cephalopelvic disproportion. An appropriate prospective study to determine the benefits of an antepartum diagnosis of cephalopelvic disproportion in high-risk nulliparas is warranted.


Maturitas | 1997

Comparison of transvaginal ultrasonography and endometrial biopsy in endometrial surveillance in postmenopausal HRT users

Willy Hänggi; Niklaus Bersinger; Hans Jörg Altermatt; Martin Birkhäuser

OBJECTIVES To compare transvaginal ultrasonography with histological findings in endometrial evaluation of postmenopausal women using hormone replacement therapy and to evaluate endometrial safety of three hormone replacement therapy regimens. METHODS In a randomized, comparative study in postmenopausal women, endometrial safety was evaluated using (1) no hormone replacement therapy, (2) oral micronized 17 beta-estradiol/oral sequential dydrogesterone, (3) transdermal 17 beta-estradiol/oral sequential dydrogesterone, or (4) oral tibolone. 85 Non-hysterectomised subjects underwent transvaginal ultrasonography immediately before Pipelle biopsy at baseline and subsequently after 12 and 24 months. Endometrial thickness and uterine dimensions were determined by transvaginal ultrasonography, and endometrial thickness (double-layer) was compared with biopsy results. RESULTS Endometrial evaluation was conveniently performed by transvaginal ultrasonography, and endometrial thickness correlated well with biopsy findings. If endometrial thickness was < 5 mm, the endometrial biopsy sample was either inactive/atrophic or insufficient for histopathological diagnosis. Hyperplastic or malignant changes were not reported. After 24 months, endometrial thickness was increased both in the oral (P < 0.001) and transdermal (P < 0.001) 17 beta-estradiol/dydrogesterone groups, whereas with tibolone the change in endometrial thickness was not different from controls. CONCLUSION transvaginal ultrasonography of the endometrium reliably predicts the histological picture in hormone replacement therapy users. Using 5 mm endometrial thickness as cut-off point, more than 75% of biopsies could be avoided. All three hormone replacement therapies were safe with respect to the endometrium. With sequential 17 beta-estradiol/dydrogesterone the expected progestogen-induced secretory pattern was observed, whereas endometrial histology under tibolone closely mimicked the natural atrophic postmenopausal state.


Journal of Assisted Reproduction and Genetics | 2001

Capacity for hormone production of cultured trophoblast cells obtained from placentae at term and in early pregnancy.

Antoine Malek; Amara Willi; Jürg Müller; Ruth Sager; Willy Hänggi; Nick A. Bersinger

Problem: There is an increased doubt about the identity of isolated cytotrophoblast cells at term. Therefore, we compared pregnancy serum levels of three hormones [human placental lactogen (hPL), human chorionic gonadotropin (hCG), and leptin] with the capacity for hormone production of early placentae [EP; 8–13 weeks of gestation (WG)] and term placentae (TP; 38–42 WG).Methods: Serum levels of these hormones were determined in 15 paired maternal (7–41 WG) and fetal (37–41 WG) samples. Cytotrophoblast cells were isolated from term (TP; 38–42 weeks) and early (EP; 8–13 weeks) placentae by enzymatic digestion and subsequent purification on a Percoll gradient. These cells were cultured for 6 days. The production of the hormones hPL, hCG, and leptin was determined as release during culture + cell content after culture − cell content before culture.Results: Serum levels (mean ± SD; n ± 15) at 7–12 and 37–41 WG were 89,652 ± 21,431 and 13,620 ± 5854 mIU/ml for hCG, 400 ± 182 and 7088 ± 2030 ng/ml for hPL, and 12,675 ± 4266 and 32,236 ± 10,961 pg/ml for leptin, respectively. For cultured cells from EP and TP, hCG and hPL showed different patterns of release during the first 2–3 days. While the release of these two hormones by EP cytotrophoblast cells continued during 6 days in culture, their concentrations reached a plateau for TP cytotrophoblasts between 4 and 6 days. Leptin was undetectable (<15 pg/ml) in TP cell cultured media, while for EP all three hormones showed the same release profiles. Production calculated for 30,000 TP trophoblast cells cultured for 6 days (n = 8) was 2–31 mIU for hCG and 0.5–2 ng for hPL. For EP (n = 11), it was 50–1070 mIU for hCG, 15–323 ng for hPL, and 137–580 pg for leptin. Net synthesis of hCG and hPL for TP was >10-fold and <1-fold, respectively. In contrast, the production of all three hormones for EP was at least 100 times the initial cell content.Conclusions: These results demonstrate that trophoblasts from early pregnancy show much higher production rates of hCG, hPL, and leptin than at term. However, the in vitro findings are difficult to be reconciled with the different serum concentrations of the two hormones hPL and leptin observed during the course of pregnancy.


Surgical Endoscopy and Other Interventional Techniques | 1998

Is laparoscopic oophorectomy rational in patients with breast cancer

Michel D. Mueller; Ekkehard Dreher; T. Eggimann; H.-R. Linder; H.-J. Altermatt; Willy Hänggi

AbstractBackground: Unsuspected malignancy remains a problem for the laparoscopic surgeon. The aim of this study was to evaluate the risk of ovarian micrometastasis in patients with breast cancer who undergo laparoscopic oophorectomy. Methods: We analyzed 25 premenopausal women with breast cancer who underwent therapeutic laparoscopic oophorectomy. The patients were subdivided into the following two groups according to ovarian pathology: group A with and group B without breast carcinoma micrometastasis. We then reviewed the follow-up data for both groups, with special attention to metastasis of the abdominal wall. Results: Twelve of 44 ovaries removed by laparoscopy showed ovarian breast carcinoma micrometastasis. There were no predictive factors of micrometastasis. After a mean follow-up of 38.1 months (95% CI: 29.2–46.9 months), none of the patients with proven micrometastasis developed metastasis of the abdominal wall, and the 21 puncture sites were inconspicuous. Conclusions: Although 32% of patients may have unexpected ovarian micrometastasis, laparoscopic oophorectomy in patients with breast cancer remains a safe procedure.


International journal of fertility and menopausal studies | 1994

Benefits of Different Routes of Administration

Martin Birkhäuser; Willy Hänggi

The benefits of hormone replacement therapy (HRT) are well established for the different systemic administration routes used today. Relief from somatic and vasomotor postmenopausal symptoms can be obtained by all recognized forms of HRT. The prophylactic action of peroral and percutaneous administration of HRT on postmenopausal bone loss is identical if the appropriate protective dosage of the estrogen component is chosen for each galenic form. The second metabolic benefit of HRT, the cardioprotective effect of ERT, is well accepted for the peroral route. New data on the direct effect of estradiol on the arterial wall as well as recent serum lipid results obtained during percutaneous administration of estradiol in postmenopausal women allow the conclusion that the percutaneous route induces cardioprotection similar to that obtained with the classical peroral route. This opinion is supported by animal data. Furthermore, observations in animals suggest that the benefits of ERT are not neutralized by either sequential or fixed addition of progestin to the estrogen. Except in some rare cases with a particular indication for either the peroral or the percutaneous administration of HRT, the choice of route of administration should be made on the basis of maximum acceptability by the patient.

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Gero Drack

Kantonsspital St. Gallen

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Elfriede Greimel

Medical University of Graz

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R. Winter

Medical University of Graz

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