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E Strehler

Publications and source records attributed to E Strehler.

At least 19 recordsLinked to original sources
PubMed2004

Effect of follicle-stimulating hormone on sperm quality and pregnancy rate.

AIM: To evaluate the possible links between ultrastructural sperm quality and the clinical pregnancy rate in infertile males treated with FSH before intracytoplasmic sperm injection (ICSI). METHODS: Forty-four infertile males with idiopathic oligo-asthenozoospermia were randomly allocated to the treated (n=24) and non-treated (control, n=20) groups. Semen analysis was carried out by light and transmission electron microscopy (TEM) before and 12 weeks after FSH therapy. ICSI was performed in all couples. RESULTS: TEM revealed a significant improvement in sperm quality after FSH treatment, particularly in men with their partners achieving clinical pregnancy. The pregnancy rate was 33 % in the treated group and 20 % in the control. CONCLUSION: RESULTS highlight a positive role of FSH therapy in infertile males before ICSI, which was correlated with an increased pregnancy rate in treated couples. We believe that improved sperm ultrastructure after FSH therapy could positively influence the quality and early stage of embryo development, thereby increasing the probability of embryo implantation.

Acrosome↗
PubMed2002

Recent advances in human sperm pathology.

Electron microscopy is a valuable tool in understanding not only the presence but also the nature of sperm malformation causing human infertility. In the past, we have examined patients affected by severe teratospermia concomitant with andrological pathologies such as varicocele, cryptorchidism, and infection. In particular, we have demonstrated that, in the case of varicocele, a combination of different phenotypic defects typical of immature spermatozoa is present. This general study was carried out on 2000 infertile men who presented for sperm analysis at our laboratory over the course of 10 years. The ejaculate of all of them was examined by electron microscopy, statistically evaluated by a formula created by us (J of Andrology, 1995), and cytogenetically checked by fluorescence microscopy techniques. First of all, this study concerned the techniques of assisted reproduction, i.e. intracytoplasmic sperm injection (ICSI), partial zona disruption (PZD), and in vitro fertilization (IVF). The conclusion was that the evaluation of the sperm quality of males attempting artificial insemination must concern not only motility or staining characteristics but mainly submicroscopical and molecular properties. Moreover, the effect of follicle stimulating hormone (FSH) treatment on human sperm quality has been evaluated by our group testing the ultrastructure and the function of spermatozoa before and after the therapy. Using the sperm as an andrological monitor, it seems that the therapeutic effect of FSH depends on the type of sperm affections. In particular, phenotypic defects as apoptosis and immaturity can be corrected by FSH treatment. More recently, we approached the problem of genotypic sperm infertility. We demonstrated that some very peculiar defects, detected by electron microscopy, show a hereditary transmission having a genetic basis. In fact, they are much more frequent in consanguineous patients, and are clearly related to different degrees of consanguinity. Frequently, chromosomal translocations have sometimes been found correlated to these defects.A consequence of these demonstrations is that most of the present sperm defects are phenotypic and can be submitted to surgical or pharmaceutical cares, but others have genetic origin and cannot be corrected by surgical or pharmaceutical treatment. These malformations are transmitted to the offspring by techniques of assisted fertilization.

Consanguinity↗
PubMed2001

Impact of recombinant follicle-stimulating hormone and human menopausal gonadotropins on in vitro fertilization outcome.

OBJECTIVE: To investigate possible differences between using recombinant FSH (rFSH) and hMG for ovarian stimulation in IVF/intracytoplasmic sperm injection (ICSI) cycles. DESIGN: Parallel group design. Prospective, randomized clinical study. SETTING: A tertiary care infertility clinic. PATIENT(S): A total of 578 patients of our IVF/ICSI routine were recruited. INTERVENTION(S): Treatment with hMG was used for 282 patients (282 cycles), whereas 296 patients (296 cycles) were treated with rFSH. The number of cycles leading to an embryo transfer were 248 and 259, respectively. MAIN OUTCOME MEASURES: Primary: clinical pregnancy rate. Secondary: treatment days, total dose of gonadotropin administered, number of oocytes retrieved, number of mature oocytes, and embryo quality. RESULT(S): Of the cycles with embryo transfer, the pregnancy rates were 30.1% and 32.3% in the rFSH and the hMG groups, respectively. This difference is not statistically significant (P=0.798). Treatment with rFSH resulted in a significantly higher number of recovered oocytes compared with the hMG group but was also associated with a higher number of ampoules needed to reach the criterion for hCG administration. No significant differences were found with regard to the number of mature oocytes, the number of treatment days, and the embryo quality. CONCLUSION(S): In terms of the clinical pregnancy rate, no significant differences between the two stimulation regimens can be stated.

Adult↗
PubMed2000

Predicting the histologic dating of an endometrial biopsy specimen with the use of Doppler ultrasonography and hormone measurements in patients undergoing spontaneous ovulatory cycles.

OBJECTIVE: To examine the relation between uterine blood flow and endometrial thickness on transvaginal Doppler ultrasonography, serum E2 and progesterone levels, and the histologic dating of an endometrial biopsy specimen obtained in the midluteal phase of a spontaneous cycle. DESIGN: Prospective clinical study. SETTING: A tertiary care infertility center. PATIENT(S): One hundred fifty-nine patients with normal menstrual cycles. INTERVENTION(S): Transvaginal Doppler ultrasonographic evaluation of uterine blood flow and endometrial thickness, determination of serum concentrations of E2 and progesterone, and endometrial biopsy. MAIN OUTCOME MEASURE(S): Resistance index, pulsatility index, serum E2 and progesterone levels, endometrial thickness, and histologic dating of the endometrium. RESULT(S): One hundred thirteen (71%) of the endometrial biopsy specimens showed complete secretory transformation and thus were classified as "in phase," and 46 (29%) of the specimens lacked some or all of the criteria for secretory transformation and thus were classified as "out of phase." There was no statistically significant difference between the in phase and out of phase groups with regard to patient age, endometrial thickness, serum hormone levels, or resistance index. The pulsatility index was significantly higher in the in phase group. The overall predictive value of the studied parameters was only 64% (sensitivity, 57%; specificity, 66%). CONCLUSION(S): Doppler ultrasonographic evaluation of uterine blood flow and measurement of hormone concentrations cannot be used to predict the histologic dating of an endometrial biopsy specimen obtained in the midluteal phase of a spontaneous cycle.

Adult↗
PubMed2000

[Are there any advantages in immediate assisted fertilization compared with differed fertilization?].

OBJECTIVES: To demonstrate a difference between the two assisted fertilization procedures. Can either of these procedures be preferred on the basis of preoperative parameters or criteria? A protocol was created to facilitate the patient's decision, as the results of IAF are better that those of DAF. METHODS: We have performed 39 in vitro fertilizations after testicular or epididymal sperm extraction since December 1995. We performed deferred assisted fertilization (DAF) in 19 patients with normal hormone assessment and normal testicular volume or after vasectomy and immediate assisted fertilization (IAF) for 20 patients with an abnormal assessment. RESULTS: The two groups, IAF and DAF, were homogeneous and did not present any differences in terms of age, aetiology of sterility, risk factors or preoperative hormonal parameters. Direct examination of sperm samples, the site of sampling and histological examination did not demonstrate any significant difference between the two groups. ICSI (IntraCytoplasmic Sperm Injection) was performed for 16 couples by IAF and for 14 couples by DAF. We obtained 6 pregnancies (37.5%) in the IAF group and 2 pregnancies (14.3%) in the DAF group. The two groups were identical in terms of the number of oocytes taken and embryos transferred. CONCLUSION: No significant difference was observed between the immediate and deferred fertilization techniques in terms of predictive factors, histology and quality of the direct examination, but the pregnancy rate was higher for IAF. We therefore think that this method should be preferred as the first-line procedure.

Adult↗
PubMed1999

Influence of ovarian stimulation on the detection of human papillomavirus DNA in cervical scrapes obtained from patients undergoing assisted reproductive techniques.

OBJECTIVE: To determine whether gonadotropin stimulation influences the detection of human papillomavirus (HPV) DNA in cervical scrapes. DESIGN: Prospective, controlled study. SETTING: Tertiary care infertility clinic. PATIENT(S): Two hundred ninety-four patients enrolled in an IVF or IUI program. Two thousand two hundred sixty-two women from an ongoing screening study who were of similar age served as a control group. INTERVENTION(S): Cervical scrapes were obtained with a cytobrush before and after ovarian stimulation with gonadotropins. MAIN OUTCOME MEASURE(S): Human papillomavirus status was assessed with a general primer (GP) polymerase chain reaction (PCR) using the GP5+/GP6+ system. In GP-PCR-positive samples, high-risk HPV types were identified with a cocktail of digoxigenin-labeled oligonucleotides. Viral load was evaluated by semiquantitative analysis of the PCR products. RESULT(S): The prevalence of high-risk HPVs was 7.8% before stimulation and 6.8% after stimulation and, thus, was similar to the prevalence in controls (8.4%). Twenty-nine patients were positive for high-risk HPVs: 14 were positive before and after stimulation, 6 were negative before and positive after stimulation, and 9 were positive before and negative after stimulation. Positivity for high-risk HPVs and viral load did not correlate directly with serum estrogen levels. CONCLUSION(S): Ovarian stimulation has no significant effect on the prevalence of HPV DNA in cervical scrapes obtained from patients undergoing assisted reproductive techniques.

Adult↗
PubMed1998

Detrimental effects of polyvinylpyrrolidone on the ultrastructure of spermatozoa (Notulae seminologicae 13).

The effect of in-vitro treatment by polyvinylpyrrolidone (PVP) on the ultrastructure of human spermatozoa has been tested previously with the statistical analysis of B. Baccetti et al. (1995, J. Androl., 16, 356-371). PVP had a primary detrimental action on the plasma membrane, as well as on acrosomal and mitochondrial membranes. Furthermore, membrane damage induces deterioration of the chromatin, axonemal tubules, fibrous sheath, and accessory fibres.

Acrosome↗
PubMed1998

Glass wool filtration leads to a higher percentage of spermatozoa with intact acrosomes: an ultrastructural analysis.

We investigated the possibility of ultrastructural damage to human spermatozoa induced by different sperm preparation techniques. Ejaculates from 20 normozoospermic men were divided into equal aliquots and processed by glass wool filtration, Percoll density gradient centrifugation, and a simple two-step centrifugation procedure which served as a control. The evaluation of 60 spermatozoa from each of 20 test subjects (in all, n = 1200) ensured that a sufficiently large number of spermatozoa were investigated. Ultrastructural damage was assessed by scanning electron microscopy. We investigated the state of the acrosome after sperm preparation and measured the percentage of intact spermatozoal structures compared with that of the control. Compared with Percoll density gradient centrifugation, glass wool filtration yielded a significantly increased proportion of intact acrosomes. However, both preparations gave significantly better results than the control. In conclusion, both glass wool filtration and Percoll centrifugation are efficient techniques for the accumulation of spermatozoa with intact acrosomes. Because of the significantly higher percentage of intact acrosomes, glass wool filtration appears to be the more appropriate method. The significance of the conspicuous bending of sperm tails after Percoll centrifugation is not yet known.

Acrosome↗
PubMed1997

The effect of follicle stimulating hormone therapy on human sperm structure (Notulae seminologicae 11).

The effects of follicle stimulating hormone (FSH) treatment on the quality of human spermatozoa were assessed by examining the ultrastructure and the function of infertile human spermatozoa using a previously-defined formula. Using the spermatozoa as an andrological monitor shows that the therapeutic effect of FSH depends on the type of sperm defect. The response to FSH is, in many cases, positive and can be evaluated by examining the state of the ejaculated spermatozoa. From an initial group of 81 patients, 15 were placebo-treated controls, and 19 were non-responders (mainly with microbially infected semen). Out of 47 responders, after therapy nine achieved improved sperm quality which approached the natural fertility threshold. These responders all had spermatozoa affected by immaturity or apoptosis (n = 27). The 20 microbially-infected responders also had immature spermatozoa and never achieved the quality level of natural fertility. Thus, a natural fertility level was only achieved by nine responders out of 27 (three with immature spermatozoa, and six with apoptotic spermatozoa). Using our method of sperm analysis, these patients' spermatozoa were clearly categorized before treatment as either immature or apoptotic. In consequence, the success of the therapy was predictable. The response of individual organelles to therapy was examined. Certain qualities of the acrosome, the chromatin, the mitochondria, and the axoneme appear to be sensitive to FSH. Most of the previous conflicting results reported in the literature may be due to a lack of relevant discrimination between the different defects present in the spermatozoa of the patients, without assessing the likelihood of their response.

Acrosome↗
PubMed1997

Submicroscopic mathematical evaluation of spermatozoa in assisted reproduction. 3. Partial zona dissection (PZD) (Notulae seminologicae 12).

This paper belongs to a series of application of the Baccetti's et al. (1995) formula to the submicroscopical mathematical examination of the human spermatozoa used for assisted reproduction. The present experiment concerns partial zona dissection, a technique requiring a careful evaluation of sperm quality in order to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of PZD. In fact the two numbers concerning the sperm ultrastructural quality (percentage and total number of spermatozoa free from defects in the ejaculate) obtained in successful and unsuccessful PZD groups, showed a large difference (P < 0.01). The most important characteristics seem to be the quality of the acrosomal complex, the condition of the chromatin and the mitochondrial assembly. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (from P < 0.05 to P < 0.01). A comparison with the results previously obtained in ICSI (Strehler et al., 1995) and IVF (Piomboni et al., 1996) shows that sperm quality is significantly more implicated in the success of IVF than of PZD or ICSI.

Female↗
PubMed1996

Submicroscopic mathematical evaluation of spermatozoa in assisted reproduction. 2. In vitro fertilization. (Notulae seminologicae. 7)

This paper belongs to a series of applications of the Baccetti et al. formula (1) to the submicroscopical mathematical examination of human spermatozoa used for assisted reproduction. The present experiment concerns IVF, a technique requiring careful evaluation of sperm quality to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of IVF. In fact the two numbers concerning sperm quality (percentage of spermatozoa free from structural defects and total number in the ejaculate of spermatozoa free from defects) obtained in successful and unsuccessful IVF groups, showed a large difference. The t distribution in both cases reached a significance of 0.005. The synthetic parameters obtained are therefore a good tool in the prediction of sperm power in in vitro insemination techniques. The most important characteristics seem to be the quality of the acrosomal complex, the status of the chromatin, the shape of mitochondria, the axonemal pattern, and the membrane integrity. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (t distribution significant at 0.005). All these data confirm that submicroscopic mathematical diagnosis offers a convincing evaluation of sperm structure and function, involving all organelles, including acrosome function and cell motility. It is also demonstrated that sperm quality is a major factor in the success of IVF and that it is clearly revealed by the integrity of the majority of the sperm organelles.

Acrosome↗
PubMed1996

Influence of smoking on fertility in women attending an in vitro fertilization program.

OBJECTIVE: To investigate the influence of cigarette smoking of women on the fertilization and pregnancy rates obtained by IVF treatment. PATIENTS: One hundred ninety-seven infertile, otherwise healthy women who entered an IVF program for the first time. SETTING: Fertility unit at the Women's University hospital of the University of Ulm, Ulm, Germany. INTERVENTIONS: The study population consisted of 197 women (23 to 39 years old) who were divided into the following groups: nonsmokers (n = 68), passive smokers (n = 26), and active smokers (n = 103) according to the cotinine concentration measured in follicular fluid. The reason for infertility was strictly a tubal factor with apparently normal ovulatory cycles. To guarantee an objective recording of tobacco smoke exposure, the smoking habit was not determined by questionnaires, but by cotinine, the principal metabolite of nicotine. RESULTS: There were no significant differences in fertilization and pregnancy rates between the different groups. The E2 serum levels were decreased significantly in women who smoked when compared with the results obtained from nonsmokers and passive smokers. Overall, a strong negative correlation of the cotinine and E2 levels was observed (r = -0.65). CONCLUSION: The results suggest that there is no clinically detectable impairment of fertilization potential due to female smoking and that there is a greater influence on the outcome of IVF by other factors.

Adult↗
PubMed1995

Predicting the success of in vitro fertilization: conventional semen analysis compared to the hamster ova penetration test.

In vitro fertilization has been advocated as a possible treatment for male factor infertility. Using data collected on 154 men, conventional semen analysis and the hamster ova penetration test are compared with respect to their power in predicting the success of assisted conception. As performing the hamster test is more expensive than the semen analysis, we also investigate a combined strategy. It performs better than the discrimination based solely on the semen parameters, but does not lead to an improvement over the overall discriminatory power obtained from the hamster test alone.

Adult↗
PubMed1995

[Idiopathic habitual abortion: experiences with active immunotherapy].

The effect of lymphocyte transfusions on the stabilisation and successful outcome of pregnancy was investigated in 30 women with recurrent abortions presumably caused by immunologic factors. Lymphocyte concentrates were obtained from stored whole blood of the husbands and transferred by intravenous injection. Exclusion criteria for this study were the presence of antipaternal lymphocytotoxic antibodies in the patient's serum (cross match) or an advanced pregnancy (> 12 weeks). After transfusion of paternal lymphocytes 19 (63%) women had uncomplicated and successful pregnancies whereas 11 (37%) suffered again from early pregnancy loss. Two out of these 11 patients aborted twice. The probability of a successful treatment decreased as soon as lymphocytotoxic antibodies appeared in the patient's serum (p < or = 0.021). Women with a lower number of abortions before treatment carried their pregnancies to full term more frequently (p < or = 0.03). The number of transfusions, the period between start of treatment and conception as well as the distribution of age within the two groups had no significant effect on the outcome of therapy. A lack of lymphocytotoxic antibodies or their late appearance during treatment give a positive prognosis for the progress of pregnancy. Compared with a fertile control group, couples with habitual abortions showed no significantly increased HLA sharing. Immunisation with paternal lymphocytes in cases of presumably habitual abortions due to immunologic factors appears as an effective therapy with only few side effects. Large, randomised, double-blind, and placebo-controlled trials are needed before drawing conclusions.

Abortion, Habitual↗
PubMed1995

[Cytogenetic abnormalities in sperm: a risk factor for application of medical reproduction techniques?].

Microinsemination techniques are increasingly applied to achieve fertilisation of the oocyte in cases of male fertility disorders. Thus, spermatozoa can directly interact with the oolemma or the ooplasm, thereby obviating the need for penetration through cumulus oophorus and zona pellucida. However, problems associated with this particular feature arise in view of the following considerations: 1. The gametes from subfertile males are suspected to carry more cytogenetic anomalies in addition to an impaired sperm quality when compared to fertile men. 2. Cumulus and zona play an important role in the selection of morphologically abnormal and dysfunctional spermatozoa. 3. Consequently, bypassing natural sperm selection processes would lead to more abnormal embryos, abortions, and births of diseased or handicapped children. Spermatozoa can be analysed cytogenetically after fusion with zona-free hamster eggs or by fluorescence in situ hybridization (FISH). Both techniques did not confirm increased aberrations in gametes from subfertile men with a normal somatic karyotype. However, a definite conclusion cannot be drawn because of the limited data and restrictions concerning their interpretation. This also holds true for the evaluation of correlations indicating no significant relationship between the chromosomal constitution and sperm motility or morphology, respectively. Currently, the risk of malformation after microinsemination does not appear to be increased when compared to conventional IVF but the results do not yet allow a reliable statistical evaluation. In contrast, decreased morphological quality, impaired implantation, and early abortions have been reported for embryos produced by assisted fertilisation. This suggests that an effective natural selection of abnormal embryos will prevent a significant increase in malformations in the following generation.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Aberrations↗
PubMed1995

[Smoking--a possible cause for failure in IVF/ET treatment?].

The aim of this study was to investigate the relation between cigarette smoking of women and the fertilisation and pregnancy rates obtained by in-vitro fertilisation treatment. To guarantee an objective recording of tobacco smoke exposure, the smoking habit was not determined by questionnaires, but by cotinine, the principal metabolite of nicotine. The study population consisted of 197 women (23-39 years old) who were divided into the groups 'non-smokers' (n = 68), 'passive smokers' (n = 26) and 'active smokers' (n = 103) according to the cotinine concentration measured in follicular fluid. The reason for infertility was strictly a tubal factor with apparently normal ovulatory cycles. There were no significant differences in fertilisation and pregnancy rates between the different groups (p > 0.05). The E2 serum levels were significantly decreased in women who smoked, compared with the results obtained from non-smokers and passive smokers (p < 0.025). Overall, a strong negative correlation of the cotinine- and E2 levels was observed (r = -0.65). The results suggest that there is no clinically detectable impairment of fertilisation potential due to female smoking and that there is a greater influence on the outcome of in-vitro fertilisation by other factors.

Adult↗