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R Mieusset

Publications and source records attributed to R Mieusset.

At least 19 recordsLinked to original sources
PubMed2006

Geographic variations in probability of pregnancy in four cities of France.

BACKGROUND: Several studies have described geographic variations in human fecundability, but this phenomenon has almost exclusively been studied at an international level rather than within a given country. Our aim was to describe geographic variations in fecundability, the monthly probability of pregnancy, between four cities of France. METHODS: We conducted a cross-sectional study in four French maternity units from Toulouse, Rennes, Lyons and Paris, among partners of pregnant women. Women were asked about the time to pregnancy (TTP) of their current pregnancy. TTP was analysed with a discrete Cox model allowing to estimate fecundability ratios (FR). RESULTS: Time to pregnancy was defined for 894 couples. There was no strong evidence of heterogeneity in fecundability between the four compared cities (p=0.05 without adjustment and p=0.25 after adjustment for behavioural and medical factors). The highest fecundability was observed in Rennes and the lowest in Toulouse (fecundability ratio (FR)=1.28, 95% CI: 1.01-1.63). Differences in fecundability were smaller between the other cities. CONCLUSION: We highlighted a possibly slightly higher fecundability in Rennes compared to Toulouse. Possible explanations for this finding are discussed. We note that the finding is consistent with previous observations indicating a higher sperm concentration among semen donors in Rennes than in Toulouse.

Cross-Sectional Studies↗
PubMed2004

Selection bias in semen studies due to self-selection of volunteers.

BACKGROUND: Reports of a secular decrease in semen quality remain controversial, particularly due to the possibility of selection bias. We aimed to describe the potential bias due to self-selection of volunteers in semen studies involving fecund men. METHODS: Using data from the French multicentre study REPRHOM, we compared the characteristics of the partners of pregnant women for three levels of participation: completion of a refusal questionnaire (n = 698), agreement to complete the study questionnaires only (n = 676) and agreement to complete the study questionnaires and give a semen sample (n = 331, 13% of the subjects approached). RESULTS: Poorly educated men refused more often to participate than highly educated men. Semen providers were more likely to have experienced unfavourable pregnancy outcomes (odds ratio 1.68, 95% confidence interval 1.14-2.49) compared with participants completing the questionnaires only. Time to pregnancy was similar for all participants. CONCLUSIONS: This study demonstrates the existence of selection bias in semen studies associated with fertility and socio-demographic characteristics of men. The results of semen analysis for this population sample cannot be extrapolated to the whole population from which the volunteers originate. More information is required on who participates, and participation rates should be reported in semen studies to make it possible to interpret the results correctly.

Adult↗
PubMed2001

Increased aneuploidy in spermatozoa from testicular tumour patients after chemotherapy with cisplatin, etoposide and bleomycin.

Testicular cancer is the most common neoplasia occurring in the young male population. The PEB (cisplatin, etoposide and bleomycin) adjuvant chemotherapy usually proposed after orchidectomy in non seminomatous tumours, and in metastatic seminomas, has improved the long-term survival of these patients. Following an azoospermic period, sperm cell recovery is generally observed after treatment delivery, but little is known about the genetic consequences on these new spermatozoa. To estimate the chromosomal consequences of this chemotherapy on sperm cells during the period of recovery of spermatogenesis, sperm cell aneuploidy was studied in testicular cancer patients, at 6-18 months after PEB adjuvant chemotherapy delivery, using fluorescence in-situ hybridization (FISH) of chromosomes 7, 16, 18, X and Y with specific DNA probes. A significant increase in the frequency of diploidy and disomy for chromosomes 16, 18 and XY was observed in treated patients compared with a healthy control group. Spermatozoa aneuploidy occurring during the spermatogenesis recovery period might be a possible side effect of the PEB regimen. Thus, practitioners should be advised to provide counselling about the need for an appropriate duration of contraception. Moreover, genetic counselling should be offered in cases of pregnancy occurring soon after the end of chemotherapy.

Adult↗
PubMed2001

Cytological detection of spermatozoa: comparison of three staining methods.

Sperm detection can be an important factor in confirming sexual assault in cases of rape. This paper compares three of the most commonly used staining methods cited in the scientific literature: Christmas tree. hematoxylin-eosin, and alkaline fuchsin. The population studied was composed of 174 consenting women seen at the Male Infertility Center in Toulouse. France. The date of their last sexual intercourse was accurately known. Alkaline fuchsin did not seem effective in detecting spermatozoa in vaginal samples. Compared with hematoxylin-eosin, Christmas tree stain appeared to be the most useful test in the first 72 h. Two external factors were associated with decreased detection of spermatozoa: time since in tercourse and sperm volume.

Coloring Agents↗
PubMed2000

Congenital bilateral absence of the vas deferens: clinical characteristics, biological parameters, cystic fibrosis transmembrane conductance regulator gene mutations, and implications for genetic counseling.

OBJECTIVE: To evaluate relationships between the phenotypic and genotypic characteristics of patients with congenital bilateral absence of the vas deferens (CBAVD). DESIGN: Retrospective study. SETTING: A university hospital urology-andrology department. PATIENT(S): Forty-one men with CBAVD. INTERVENTION(S): CBAVD was diagnosed during surgical and/or ultrasound exploration of the vasa deferentia (VD) (n = 39), or on the basis of impalpable scrotal VD (n = 2). MAIN OUTCOME MEASURE(S): History, clinical and seminal characteristics, and cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations including IVS-8 polyT analysis. RESULT(S): A palpable scrotal vas deferens was present as a fibrous cord or nonpermeable duct in 13% of patients undergoing surgical exploration. Seminal vesicles were bilaterally absent in 28% of patients. No CFTR gene mutation or 5T allele was detected in 24.5% of the patients. Two CBAVD patients with renal agenesis carried a CFTR gene mutation (DeltaF508/5T-9T and R117G/7T-9T). CBAVD patients who have both a semen volume of < or =1.0 mL and a semen pH of < 7.0 have a significantly higher risk of severe CFTR gene mutation (OR = 9.12 [95% CI = 1.81-49.50]). CONCLUSION(S): A palpable scrotal vas deferens was found in 13% of CBAVD patients. Semen volume of < or =1.0 mL and semen pH of < 7.0 in CBAVD patients were associated with a higher risk of severe CFTR gene mutations. Patients with CBAVD and renal agenesis should be screened for CFTR gene mutations before assisted reproductive techniques are used.

Abnormalities, Multiple↗
PubMed2000

Increase in scrotal temperature in car drivers.

Several recent studies have reported a gradual decline in sperm production in men. Endocrine disrupters as well as lifestyle have been suggested as risk factors. One lifestyle factor that may affect human fertility is driving a vehicle for a prolonged period. Several authors have suggested that driving position may increase the scrotal temperature. In order to validate this hypothesis we conducted continuous monitoring of scrotal temperature in real conditions, i.e. in men driving a car for a prolonged period. Nine volunteer men were asked to walk outside for 40 min and then to drive a car for 160 min. Scrotal temperatures were measured from thermocouples and values recorded every 2 min on a portable data recorder. Scrotal temperature increased significantly (P < 0.0001) in driving posture after 2 h of driving, reaching a value 1.7-2.2 degrees C higher than that recorded while walking. This link between driving position and increased scrotal temperature indicates a potential exposure of male reproductive function to lifestyle factors.

Adult↗
PubMed1998

Clinical characteristics and light and transmission electron microscopic sperm defects of infertile men with persistent unexplained asthenozoospermia.

OBJECTIVE: To determine, with the use of transmission electron microscopy (TEM), the proportion of patients with permanent unexplained asthenozoospermia (<30% motility) who have an abnormality of sperm axonemal and periaxonemal structures. DESIGN: Retrospective study. SETTING: A university-affiliated public hospital. PATIENT(S): Sixty-one infertile men whose semen was submitted to TEM analysis because of persistent unexplained asthenozoospermia. MAIN OUTCOME MEASURE(S): The results of quantitative TEM analysis of the tails of the spermatozoa. INTERVENTION(S): None. RESULT(S): Based on a comparison with the axonemal anomalies observed in nine fertile control patients, the infertile population was divided into three groups: group I, with no detectable axonemal defects (26.2%); group II, with axonemal anomalies in either the midpiece or the principal piece (29.5%); and group III, with axonemal anomalies in both the midpiece and the principal piece (44.3%). However, defects in the mitochondrial sheath, fibrous sheath, and sperm head (acrosomic and postacrosomic cap) were observed in at least 50%, 30%, and 50%, respectively, of the patients in each group. The proportion of dense fiber anomalies of the midpiece increased significantly from group I to group III. No differences were observed between the three groups in sperm characteristics, anamnesis information, or clinical data. CONCLUSION(S): In patients with persistent unexplained asthenozoospermia, the frequent association of periaxonemal anomalies with axonemal deficiencies strongly suggests that axonemal deficiencies are not the unique cause of decreased motility.

Adult↗
PubMed1998

Quantification by magnetic resonance spectroscopy of metabolites in seminal plasma able to differentiate different forms of azoospermia.

The aim was to determine whether proton magnetic resonance spectroscopy (1H-MRS) of metabolites such as glycerophosphorylcholine (GPC), choline, citrate and lactate in human seminal plasma can be used to differentiate (i) different azoospermic patients and (ii) different forms of spermatogenic failure including those who had undergone radiation therapy or chemotherapy. Semen samples were provided by men with obstructive azoospermia and spermatogenic failure who had serum follicle stimulating hormone (FSH) values within the normal range and either more or less than normal. Four prominent constituents of seminal plasma were identified by 1H-MRS: GPC, choline, citrate and lactate. The peak area ratios of choline/citrate as well as choline/lactate were significantly different (P < 0.01) between groups with spermatogenic failure and obstructive azoospermia. When the serum FSH values were normal in men with spermatogenic failure and obstructive azoospermia, a significant difference was found in the GPC/choline ratio (P < 0.001). When the FSH values were normal, the GPC/choline ratio appeared to be a very important parameter able to differentiate not only between cases of spermatogenic failure and obstructive azoospermia but also between different forms of spermatogenic failure. These results demonstrate the potential use of 1H-MRS on human seminal plasma in a new approach in the management of male infertility.

Antineoplastic Agents↗
PubMed1998

Occupational heat exposure and male fertility: a review.

In humans, as in most mammals, spermatogenesis is temperature dependent. This temperature dependence has been clearly demonstrated by several experimental studies showing that artificial increases in scrotum or testicle temperature in fertile men reduce both sperm output and quality. Our knowledge of the effects of occupational heat exposure on male fertility comes mostly from a small number of epidemiological studies. We conducted an extensive review of these published reports, focusing on methodology and design (retrospective or prospective; reference group; number of subjects) and principal results (using several indicators such as the time taken to obtain a pregnancy or sperm characteristics). We concluded that occupational heat exposure is a significant risk factor for male infertility, affecting sperm morphology and resulting in delayed conception. The limits and biases involved in this type of research are also discussed.

Animals↗
PubMed1997

Effect of male occupational heat exposure on time to pregnancy.

The relationship between male occupational heat exposure and the time required to achieve a pregnancy [TTP] was studied in a retrospective survey of 402 fertile couples. The TTP for t he subgroups 'exposure t o heat' (median = 4 .0 months; mean 11.8; SD = 13.3) and 'professional driver >3 h/day' (median = 4.5; mean = 14.4; SD = 28.5) was significantly longer (both p < 0.05) than for the controls (median = 2.8; mean = 7.8; SD = 13.3). Bakers and welders showed comparable results: only 14% of the bakers' partners became pregnant within 3 months (cf. 55% of controls, p < 0.05) and only 29% became pregnant within 6 months (cf. 74% of controls, p < 0.02). This study suggests that occupational exposure to heat is a 'weak' risk factor for male subfertility.

Adult↗
PubMed1997

Inconstant ascending testis as a potential risk factor for spermatogenesis in infertile men with no history of cryptorchism.

The usual testicular location, either low or high in the scrotum, as well as testis ascent into suprascrotal position at least once a week from a usually scrotal position reported by the patient to occur spontaneously and regularly, were recorded in 85 fertile and 1014 infertile men, including 95 with a history of cryptorchism. The frequency of at least one testis being in a high scrotal location was similar in fertile (16.5%) and non-cryptorchid infertile (17%) men but higher in previously cryptorchid infertile men (27.2%), a difference probably due to cryptorchism. Testicular ascent was more frequent when scrotal location was high rather than low. An ascending testis was encountered more frequently in previously cryptorchid (30.4%) than in non-cryptorchid infertile men without any history of cryptorchism (18.3%) or in fertile men (11.8%). Moreover, in infertile men, spermatogenesis was more depressed in cases of testicular ascent than when both testes were never ascending, independently of a varicocele. Testis ascent could be a risk factor for spermatogenesis in infertile men without any history of maldescended testicle.

Adult↗
PubMed1997

Cytomegalovirus detection in cryopreserved semen samples collected for therapeutic donor insemination.

The presence of cytomegalovirus (CMV) in semen was retrospectively evaluated in 178 cryopreserved semen samples obtained from 97 donors recruited by two sperm banks. Thirty-three (34.0%) donors were CMV-seronegative, 51 (52.6%) were CMV-seropositive and 13 (13.4%) had an unknown serological status. CMV was detected in sperm specimens by cell culture and polymerase chain reaction (PCR). CMV was detected in five (2.8%) samples from two (2.0%) donors by cell culture and in 10 samples (5.6%) from five donors (5.1%) by PCR; all the samples which were positive by cell culture were also positive by PCR. Our data indicate that cryopreserved semen specimens obtained from healthy volunteer donors represent a potential source of CMV infection through therapeutic donor insemination. PCR, which is more sensitive than cell culture, should be used for direct and rapid identification of CMV in semen samples collected from volunteer donors. CMV detection in semen by PCR could be advantageously compared to CMV-antibody tests in serum which are only indicative of a former CMV infection.

Adult↗
PubMed1996

Time series analysis of sperm concentration in fertile men in Toulouse, France between 1977 and 1992.

OBJECTIVES: To investigate whether sperm production has changed during the past 16 years in the Toulouse area of France. DESIGN: Time series analysis of sperm donors' specimens between 1977 and 1992. SETTING: Sperm bank of university hospital in Toulouse, France. SUBJECTS: 302 healthy fertile men candidate sperm donors more than 20 and up to 45 years old and without any infertile brothers. MAIN OUTCOME MEASURE: Spermatozoa concentration. RESULTS: Donors' mean age at time of donation was 34.05 (SD 5.13), but this increased significantly (P<0.001) during the study, from 32.4 in 1977 to 36 in 1992. Mean sperm count of samples was 83.12x10(6)/ml (SD 68.42x10(6)/ml). Sperm concentration was positively linked to the year of donation (Pearson's coefficient r=0.12, P<0.05), but this correlaton disappeared after adjustment for age of donors (r=0.09,P>0.05). CONCLUSION: Sperm concentration has not changed with time in the Toulouse area.

Adult↗
PubMed1996

Are the characteristics of spermatozoa in the insemination medium useful for predicting in-vitro fertilization results?

To determine whether the characteristics of Percoll-selected spermatozoa are more predictive of in-vitro fertilization (IVF) results than are those of native semen, 118 semen samples from patients undergoing an IVF attempt were studied. Motility, using computer-assisted sperm analysis, and morphology were recorded before and after sperm selection on a Percoll gradient. Percoll selection increased the percentage of morphologically normal spermatozoa (58.2 +/- 19.9% versus 47.9 +/- 17.9%; p < 0.0001). This increase concerned almost all abnormalities and especially abnormalities of the midpiece (cytoplasmic droplets and bent tails). However, morphology of spermatozoa in the Percoll fraction had the same predictive value for IVF as did that for whole semen. Concerning motility, all parameters, except linearity, were improved by Percoll preparation, and their predictive value for IVF results was significantly higher in the Percoll fraction than in native semen. Therefore, it is concluded that, even if sperm characteristics are improved dramatically after Percoll selection, only motility analysis then gave more practical information than did analysis of sperm characteristics in native semen. This suggests that impairment of spermiogenesis, which presumably induces sperm abnormalities, is more important than are the actual characteristics of the spermatozoa.

Female↗