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Biomedical subjects

F Comhaire

Publications and source records attributed to F Comhaire.

At least 55 records · Page 3Linked to original sources
PubMed1995

Varicocele: indications for treatment.

Varicocele is detected in about one-third of men with subfertile semen quality. Treatment by means of transcatheter embolization using the tissue adhesive Histoacryl improves Sertoli cell function with increased concentrations of transferrin in semen, and a significant increase in sperm concentration, normal morphology and linear velocity. Failure to attain pregnancy after varicocele treatment occurs if pre-treatment sperm quality is normal, or in the case of azoospermia with elevated blood FSH levels or obstruction, or when there is severe coincidental pathology impairing fertility of the male or female partner. In all other cases, the poor results of varicocele treatment reported in some studies can only be explained by inadequate techniques. Varicocele detection and embolization treatment at puberty or during adolescence should be advocated to prevent deterioration of testicular function.

Humans↗
PubMed1995

Statement on intra-uterine insemination.

Treatment of couple infertility due to male subfertility by means of intra-uterine insemination (IUI) gives better results, in terms of per cycle and total cumulative pregnancy rate, if sperm preparation is performed using a discontinuous Percoll gradient than if centrifugation-resuspension is used. Also, the minimal semen requirements for successful IUI are lower with the former technique. Optimal epididymal function, with total alpha-glucosidase activity in seminal plasma > 83 IU/mL or Schorr stain result > 60%, is associated with a high probability of success of IUI [odds ratio (OR) = 11.1 and 9.4 respectively; p < 0.01]. If semen contains > 2.3 million white blood cells per mL or more than 13 million spermatozoa/mL with grade a motility the success rate is decreased (OR = 0.25 and 0.30 respectively; p < 0.05 and p < 0.01). It is concluded that IUI is a highly successful treatment in specific cases of male subfertility, provided that the correct technique of sperm preparation is used.

Humans↗
PubMed1994

Methodological aspects of sperm morphology evaluation: comparison between strict and liberal criteria.

OBJECTIVE: To compare the methodological accuracy of different sperm morphology criteria. SETTING: A multicenter study including 10 laboratories with high expertise in semen analysis. PATIENTS: Semen preparations of subfertile men with a variable degree of teratozoospermia and of fertile semen donors. INTERVENTIONS: Detailed assessment of sperm morphology on 10 air-dried semen smears, of which 3 originated from the same ejaculate. RESULTS: The average coefficient of variation calculated on the three smears of the same ejaculate was higher when strict criteria for morphological normality were used and borderline cells were classified as abnormal than when criteria of abnormality were applied and borderline cells were considered normal. The correspondence between individual centers mutually and of each center with the average result of all centers was better when the latter approach was taken. The performance of two computer-assisted systems was intermediate between that of the two approaches, whereas one system gave unreliable results. CONCLUSIONS: Strict criteria for normality of sperm morphology, with borderline cells considered abnormal, gives results that are less reproducible and less accurate than the approach that classifies sperm as abnormal, with borderline cells considered normal.

Fertility↗
PubMed1994

Methods to increase the success rate of artificial insemination with donor semen.

Donor insemination was performed in two fertility clinics using cryopreserved semen from the same sperm bank. Donors were selected in agreement with American Fertility Society recommendations. In the first clinic, cup insemination was combined with intra-uterine insemination in 321 cycles. Follicular development was closely monitored with vaginal echography and serum hormonal measurements. In the second clinic, 1287 insemination cycles were performed using intra-cervical insemination, timed only on basal body temperature. In the first clinic, a total of 53 pregnancies were obtained, of which seven were in 55 unstimulated cycles (12.5%), 21 in 159 cycles with clomiphene citrate stimulation (13.1%, P > 0.1), and 25 in 107 cycles stimulated with clomiphene plus human menopausal gonadotrophin (HMG) (23.9%, P < 0.03). No multiple pregnancies were observed in the latter group. In the second clinic, 159 pregnancies occurred during 1287 insemination cycles (12.4%). It is concluded that neither intra-uterine insemination, nor hormonal and echographic cycle monitoring, nor clomiphene citrate enhances the success rate of artificial insemination with donor semen, but HMG treatment probably exerts a favourable effect.

Adult↗
PubMed1992

Pilot study with 120 mg Andriol treatment for couples with a low fertilization rate during in-vitro fertilization.

Treatment with 120 mg/day of Andriol (testosterone undecanoate; Organon, The Netherlands) was given to 11 men whose semen had either failed to fertilize, or had resulted in a less than 33% fertilization rate in a first in-vitro fertilization (IVF) trial. Repeat IVF at the end of a 3 month treatment period resulted in a highly significant increase in the number of oocytes fertilized from 4/95 (4.2%) before to 23/87 (26.4%, P less than 0.001) after Andriol treatment. One couple attained spontaneous conception during the second month of Andriol intake and three pregnancies occurred among the remaining 10 cases undergoing repeat IVF, for a total ongoing pregnancy rate of 36.4%. Sperm concentration but not motility increased in the native semen after Andriol intake, but there were no significant changes in sperm characteristics after preparation. The improvement in pregnancy rate contrasts favourably with the results obtained by repeat IVF of untreated historical controls. The result obtained in the present pilot study should encourage the performance of a larger, placebo-controlled investigation protocol.

Female↗
PubMed1991

Placebo-controlled trial of high-dose Mesterolone treatment of idiopathic male infertility.

The possible effect of Mesterolone (Schering N.V., Brussels, Belgium) (1 alpha-methyl-5-alpha-androstane-17 beta-ol-3-one) on semen quality and fertility of men with idiopathic oligoasthenospermia and/or teratozoospermia has been evaluated in a double-blind trial. The study included 52 patients who were treated during 12 months with either 150 mg/d of Mesterolone or placebo. The overall pregnancy rate was similar in the Mesterolone-treated cases (26%) and in the placebo control cases (48%), although a significant increase in motility and in the proportion of spermatozoa with normal morphology was recorded in the Mesterolone-treated cases. Because similar semen improvement also occurred in the placebo controls, our findings cast doubt on the possible usefulness of high-dose Mesterolone treatment of idiopathic male infertility.

Administration, Oral↗
PubMed1990

Treatment of idiopathic testicular failure with high-dose testosterone undecanoate: a double-blind pilot study.

The effect of high-dose (240 mg/d) intake of testosterone (T) undecanoate was studied for sperm characteristics, function of the accessory sex glands, and hormonal parameters of men with idiopathic oligozoospermia, asthenozoospermia, or teratozoospermia using a two-phase protocol including a 3-month double-blind period followed by a 3-month open phase. Increased sperm viability and semen content of adenosine triphosphate were either not reproducible after patients on placebo were switched over to T undecanoate or did not reach statistical significance, whereas no changes were detected in other sperm characteristics and the accessory sex glands. Intake of T undecanoate significantly increased the concentration of 5-alpha-dihydrotestosterone (DHT) and the ratio of DHT over T in peripheral blood, suppressed the luteinizing hormone concentration, and tended to decrease serum follicle-stimulating hormone concentration. It is concluded that high-dose T undecanoate is not effective in the treatment of men with infertility with idiopathic testicular failure.

Dose-Response Relationship, Drug↗
PubMed1990

Possibilities and limitations of techniques of assisted reproduction for the treatment of male infertility.

Since relatively few spermatozoa are needed for oocyte fertilization during gamete intra-Fallopian transfer (GIFT) or in-vitro fertilization (IVF), these methods have been applied in couples with infertility due to male causes. Forty-six couples with male factor infertility were enrolled in this study and results were compared with those attained in 48 couples treated with the same techniques for other than male causes. Overall, GIFT resulted in 26% ongoing pregnancies. GIFT seems to be particularly successful when the sperm concentration is 20 x 10(6)/ml or more, but sperm motility and/or morphology are poor. Nine pregnancies occurred out of 26 GIFT cycles in 18 cases selected on this basis. The ongoing pregnancy rate after IVF was 16% per patient. The latter treatment should be attempted in male immune infertility and in cases with a low sperm concentration, with or without abnormal sperm motility and/or morphology. In these circumstances, five pregnancies were attained out of 28 cycles in 14 cases. For similar sperm concentrations, the conception rate per cycle attained with techniques of assisted reproduction was more than twice that attained with conventional treatment of male infertility.

Female↗
PubMed1990

Value of sperm characteristics and the result of in-vitro fertilization for predicting the outcome of assisted reproduction.

The outcome of procedures for assisted reproduction, namely in-vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) were used as end-points to assess the capacity of particular sperm characteristics to predict the fertilizing potential of semen. In addition, the result of IVF performed with spare oocytes from the GIFT procedure, was used to predict the pregnancy outcome of GIFT. The power of sperm characteristics to predict the outcome of assisted reproduction procedures was poor. With regard to the outcome of IVF, sperm morphology was the best discriminant. The threshold value of 16% normal sperm morphology could be used as a good predictor of successful IVF, but could not be applied as a criterion to reject an IVF trial. For the latter purpose, the limit of 5% sperm with normal morphology should be used. The proportion of sperm with grade A motility in native semen provided the best discrimination between GIFT-fertile and GIFT-infertile cases. A negative result from IVF performed with spare oocytes was 93% accurate in predicting unsuccessful outcome of GIFT. Hence, diagnostic IVF is the most sensitive assay for male fertility. The occurrence of oocyte fertilization during IVF predicts a successful outcome of GIFT in only 50% of cases. Hence, a negative result in IVF indicates that semen is almost certainly infertile, but a positive result does not guarantee the successful outcome of GIFT.

Adult↗
PubMed1989

Effect of different procedures of semen preparation on antibody-coated spermatozoa and immunological infertility.

To assess whether procedures of semen preparation can reduce the proportion of antibody-coated spermatozoa, semen samples with positive direct mixed antiglobulin reaction (MAR) were washed in media supplemented with 10% or 50% fetal cord serum (FCS). Washing reduced the MAR to a negative level, but the MAR was identical to that in the native semen when spermatozoa were resuspended in serum-free medium. Donor spermatozoa, recovered after swim-up in media supplemented with 10% or 50% FCS or after passage through a column with 7.5% human serum albumin (HSA), were incubated in serum samples with both agglutinating and cytotoxic antisperm antibodies. Cytotoxic activity was significantly reduced against sperm filtered over the albumin column.

Agglutinins↗
PubMed1988

Evaluation of a simplified adenosine triphosphate release cytotoxicity test for the detection of sperm antibodies in human serum.

The adenosine triphosphate release cytotoxicity test (ARCT) is an objective method for the detection of cytotoxic sperm antibodies in serum providing measurements without the bias of microscopic estimation. The procedure has been simplified by testing only one serum dilution and calculating the "sperm toxicity index". The latter is closely correlated with the sperm cytotoxic titer. Immunoglobulin class determination of 32 sera with sperm cytotoxic activity was performed by means of the indirect mixed antiglobulin reaction (MAR test) and the indirect immunobead (IB) test, and revealed that all sera were positive for IgG, 17% for IgM and 20% for IgA. Of 32 sera without sperm cytotoxic activity, 19% contained sperm specific IgG, 6% had IgM class antibodies belong mainly to the IgG class since the results of the ARCT and the indirect MAR test for IgG are closely correlated. The ARCT appears to be useful as a simple and objective method for the detection and quantitation of cytotoxic antisperm antibodies.

Adenosine Triphosphate↗
PubMed1988

The indirect mixed antiglobulin reaction test using a commercially available kit for the detection of antisperm antibodies in serum.

A simple procedure is described for the detection of antisperm antibodies of the IgG class in human serum using the indirect mixed antiglobulin reaction (MAR) test. The test uses only one dilution of serum (1/16) and no washing procedures. The test was performed in 361 sera. Comparative studies were conducted with the tray agglutination test (TAT) in 164 sera and with the direct MAR test on semen in 110 cases. In 24 sera with borderline test results, and in 13 sera with discordant findings, evidence of antisperm antibody activity was investigated by means of additional testing, namely, the adenosine triphosphate release cytotoxicity test (ARCT) and the indirect immunobead tests (IB) for IgA and IgM. Using the value of 40% reaction between motile spermatozoa and coated latex particles as the lower limit of significant activity, the indirect SpermMAR test has a sensitivity of 96% and specificity of 87%. The two false-negative indirect MAR results occurred in cases with IgM, the clinical significance of which is doubtful. Hence, the indirect MAR test appears to be an ideal screening procedure for sperm antibodies in serum since it is easy to perform and sensitive. Considering the false-positive rate of 13%, additional tests should, however, be performed on sera with a reaction of 40% or more in order to assess the relevance of the antibodies as a cause of infertility.

Agglutination Tests↗
PubMed1988

Capacity of objectively assessed sperm motility characteristics in differentiating between semen of fertile and subfertile men.

A simple and inexpensive computer-assisted method for the objective assessment of sperm motility characteristics was employed to evaluate semen samples of 42 fertile men and 70 subfertile patients. The capacity of each motility parameter to discriminate between semen of the two groups was evaluated by receiver operating characteristic curve analysis. Velocity, linear velocity, and "angular" velocity are reasonably accurate, whereas linearity and angularity index had a very poor discriminating power. The best discrimination between the two groups was the proportion and concentration of sperm with rapid linear progressive motility, based on the cut-off value of linear velocity greater than or equal to 22 microns/sec. This parameter was 90% accurate in discriminating semen of infertile men from that of subfertile patients.

Diagnosis, Computer-Assisted↗
PubMed1988

Validation of a single-step procedure for the objective assessment of sperm motility characteristics.

A relatively cheap method is described for the objective assessment of sperm concentration and motility characteristics. The method uses a digitizing tablet with cursor, a micro-computer and a phase-contrast or dark-field microscope equipped with a drawing tube. With this technique the following are accurately assessed: sperm concentration, percentage motility, motility grading, concentration of grade a motile spermatozoa, sperm velocity, linear velocity, linearity and angularity. The data are acquired in less than 5 min. Validation studies reveal this method to be accurate, reproducible (coefficient of variation of motility characteristics = less than 7%) and clinically useful.

Algorithms↗
PubMed1985

Altered glycosylation of gamma-glutamyltranspeptidase (GGT) in seminal fluid from men with accessory gland infection.

The heterogeneity of gamma-glutamyltranspeptidase (GGT) in seminal plasma has been studied using Con A-chromatography. This parameter was then related to the fructose concentration, the acid phosphatase activity, ejaculate volume, sperm density and the number of bacteria per ml. Multivariate regression analysis and stepwise elimination of the least fitting factors, revealed that Con A-binding correlated with the number of bacteria per ml of semen and the acid phosphatase activity with 49% of the variance of GGT-binding being explained by these parameters. This result suggests that glycosylation of seminal GGT is altered by accessory gland infection. Neuraminidase digestion suggests that the pattern of Con A-binding of seminal GGT depends only partly on its sialic acid content.

Acid Phosphatase↗