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Dive into the research topics where Luis J. Rodriguez-Rigau is active.

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Featured researches published by Luis J. Rodriguez-Rigau.


Fertility and Sterility | 1977

Frequency Distribution Of Sperm Counts In Fertile And Infertile Males

Zvi Zukerman; Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

In this study the frequency distribution of sperm counts and total sperm counts from more than 4000 allegedly fertile males were compared with those of husbands in 1000 infertile couples. Significant differences were observed only at the lower end of the scale (sperm counts below 10 million/ml and total sperm counts below 25 million/ejaculate). Frequency distributions of sperm counts above 10 million/ml or total sperm counts above 25 million/ejaculate revealed little difference between the fertile and infertile groups. These data suggest that, unless other parameters are found to be abnormal, sperm counts and total sperm counts above 10 million/ml and 25 million/ejaculate, respectively, probably are not major factors in a couples infertility.


Fertility and Sterility | 1977

Relation between indices of semen analysis and pregnancy rate in infertile couples.

Keith D. Smith; Luis J. Rodriguez-Rigau; Emil Steinberger

Both partners of 198 consecutive infertile couples were evaluated. Studies in the female included clinical evaluation of ovulation for a minimum of two menstrual cycles, investigation of tubal patency, and evaluation of sperm survival in cervical mucus. Six semen specimens were analyzed from each male. Laparoscopy, scrotal exploration, and testicular biopsies were performed as required. Where indicated, the female was treated intensively. The only therapy offered to the males was ligation of varicoceles, if present. The couples were grouped on the basis of sperm counts, total sperm counts, motile sperm counts, and total motile sperm counts, and the incidence of pregnancy was computed. Pregnancy rates of approximately 50% occurred in couples where sperm counts or total sperm counts were in the range of 5 to 60 million/ml or 25 to 200 million/ejaculate, respectively. When sperm counts were over 60 million/ml or total sperm counts over 200 million/ejaculate, pregnancy rates increased to above 70%. These observations emphasize the importance of considering infertility as a problem of a couple rather than as a specific disorder of one of the partners. These data also demonstrate a lack of direct correlation between sperm density in the ranges of 5 to 60 million/ml and pregnancy rates in couples where the wife is treated intensively.


The Journal of Urology | 1978

Relationship of varicocele to sperm output and fertility of male partners in infertile couples.

Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

Both partners of 455 infertile couples seen consecutively were evaluated. When indicated the female partners were treated. Six semen specimens from each male subject were analyzed. A varicocele was diagnosed in 23.7 per cent of the men. More than 60 per cent of the men with a varicocele had sperm counts less than 40 million per ml., while 67 per cent without a varicocele had sperm counts more than 40 million per ml. The mean and total sperm counts of men with a varicocele were significantly lower than those without a varicocele. However, the pregnancy rates were not significantly different. The pregnancy rate was 46 per cent in couples whose male partners underwent a varicocelectomy, not significantly different from the pregnancy rate achieved in couples when the varicoceles were not corrected surgically (51 per cent). Varicocelectomy resulted in improvement in sperm count only when preoperative counts were more than 10 million per ml. Pregnancy rates for couples in which a varicocelectomy did or did not result in improvement in sperm count or motility were identical (45.1 and 45.5 per cent, respectively). These findings suggest that in male partners of infertile couples the presence of a varicocele is associated with compromised semen quality but not with diminished fertility when the female partners are treated. This observation emphasizes the importance of considering infertility as a problem of a couple, rather than a specific disorder of one of the partners.


The Journal of Urology | 1978

Leydig Cell Function in Oligospermicmen with Varicocele

David B. Weiss; Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

Abstract: We report on the evaluation of Leydig cell function in 16 young men with sperm counts less than 10 million per ml. and with various degrees of unilateral or bilateral varicocele. An in vitro technique of incubation of testicular tissue with radiolabeled precursors was used for evaluation of Leydig cell androgen synthesis. A significant suppression of in vitro testosterone formation was observed in almost 90 per cent of the patients. Circulating testosterone and luteinizing hormone levels were within the normal range. However, when the patients were grouped according to the in vitro testosterone synthesis data a correlation between the circulating testosterone and gonadotropin levels was observed. Sperm motility was highest for patients with highest testosterone synthesis rates. No correlation among the ages of the patients, size of varicocele, degree of oligospermia or histologic appearance of the seminiferous epithelium could be demonstrated. An increased Leydig cell number was observed in test...


Fertility and Sterility | 1981

The influence of ovulatory dysfunction and timing of insemination on the success of artificial insemination donor (aid) with fresh or cryopreserved semen

Keith D. Smith; Luis J. Rodriguez-Rigau; Emil Steinberger

The influence of ovulatory dysfunction and timing of insemination on the success of AID with either fresh or cryopreserved semen was investigated. A total of 238 patients were inseminated, resulting in 170 pregnancies during 1201 insemination cycles, an average of 5.0 cycles per pregnancy. Pregnancy rates were similar in those patients receiving either fresh or cryopreserved semen, but the number of cycles required for pregnancy to occur was doubled in the latter group. Ovulatory dysfunction further delayed the number of cycles before conception. The poorest results occurred in those patients with ovulatory dysfunction receiving cryopreserved semen. The timing of insemination was more important in patients receiving cryopreserved semen than those receiving fresh semen. With cryopreserved semen, pregnancy was not likely to occur unless the insemination was performed on the day of ovulation. These data suggest that frozen semen is less efficacious than fresh semen, a difference that is compounded by the presence of ovulatory dysfunction in the recipient. It is possible that an increase in the frequency of insemination from every other day to daily may improve the results of AID with cryopreserved semen.


Fertility and Sterility | 1982

Cigarette smoking and semen quality

Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

In order to further investigate the findings of earlier studies the authors conducted a study of semen quality in 437 consecutively seen male partners of infertile couples and excluded 181 men who exhibited factors which could have influenced semen quality. A group of 97 men with varicocele was considered separately. Of the remaining 159 men, 101 were nonsmokers and 58 were smokers, age being approximately 31 years. The average percentage of normal spermatozoa was 44.7% for the group of 101 nonsmokers and 44.8% for the group of smokers. Average sperm motility, mean sperm count and frequency distribution of sperm were also not very different between the 2 groups. Amount of cigarettes smoked per day did not matter. The group of 97 men with varicocele which was analyzed separately showed no differences between smokers and nonsmokers although when compared with the group of 159 men without varicocele a significantly higher percentage of men with varicocele had sperm counts of 20 million/ml. It is difficult to explain the differences between these findings and those that claim that smoking does affect sperm quality. The subject of possible detrimental effects of cigarette smoking on semen quality is controversial and studies of larger groups need to be done.


Fertility and Sterility | 1979

Effect of Prednisone on Plasma Testosterone Levels and on Duration of Phases of the Menstrual Cycle in Hyperandrogenic Women

Luis J. Rodriguez-Rigau; Keith D. Smith; Robert K. Tcholakian; Emil Steinberger

A group of 106 women of reproductive age with laboratory and clinical evidence of hyperandrogenism was treated with prednisone. The daily dosage varied between 7.5 and 10 mg. Ovulatory activity was assessed prior to and during therapy by basal body temperature and observation of changes in the cervical os and cervical mucus. Plasma testosterone levels were significantly suppressed by prednisone therapy. This was associated with initiation of ovulatory activity in 5 of 14 (35.7%) amenorrheic patients and 10 of 11 (90.9%) anovulatory patients. In 81 ovulatory patients, prednisone therapy resulted in statistically significant shortening of the follicular phase and lengthening of the luteal phase of the menstrual cycle. The mean length of the menstrual cycle was unchanged. Significant correlations between percentage suppression of plasma testosterone and shortening of the follicular phase or lengthening of the luteal phase were observed. Suppression of plasma testosterone by prednisone was maximal after 2 months of treatment, while the effect on the phases of the menstrual cycle was progressive with duration of treatment. The effects of prednisone at daily dosages of 7.5 or 10 mg were not significantly different. These results suggest that prednisone therapy in hyperandrogenic women exerts an effect on both phases of the menstrual cycle, possibly related to suppression of plasma testosterone levels.


Journal of The American Academy of Dermatology | 1984

Acne and hyperandrogenism

Beverly L. Held; Shahla Nader; Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

Elevated serum androgen levels have been reported in patients with acne resistant to conventional dermatologic therapy. This study was designed to investigate the relationship between serum androgen levels and the presence of acne in an unselected population of women seen consecutively by a dermatologist for various dermatologic complaints. Elevated serum testosterone levels were associated with acne regardless of whether this was the presenting complaint or an incidental finding. Women with both acne and hirsutism had higher serum testosterone levels than those with acne alone. Higher incidence of irregular menstrual cycles was noted in women complaining of acne. Normal serum testosterone levels were found only in those patients with regular menstrual cycles and the absence of acne or hirsutism. In conclusion, this study suggests that elevated serum testosterone levels are related to the presence of acne. Attention is called to the possibility that acne may be a clinical manifestation of a disorder with systemic and reproductive consequences.


Steroids | 1977

In vitro steroid metabolic studies in human testes I: Effects of estrogen on progesterone metabolism

Luis J. Rodriguez-Rigau; Robert K. Tcholakian; Keith D. Smith; Emil Steinberger

A technique of incubation of testicular tissue in vitro with radiolabeled precursors was applied in the investigation of the steroid biosynthesis by testes of four young men after long-term, high-dose estrogen treatment. A positive correlation between plasma and testicular steroid levels, and in vitro capacity of the testes to metabolize progesterone was demonstrated. Estrogen administration produced a very significant inhibition of plasma and testicular levels of testosterone. The in vitro synthesis of testosterone from progesterone was very severely impaired; especially 17alpha-hydroxylation of progesterone. 20alpha-hydroxysteroid-dehydrogenase activity was found to be increased after estrogen treatment, both in vivo and in vitro. These findings suggest that testicular 17alpha-hydroxylase activity (and possibly also 17-20 lyase activity) is either under gonadotropin regulation, or is directly suppressed by estrogen. This could result by decreased enzyme synthesis, direct enzyme inhibition or affectation of the cofactors or cytochromes necessary for the enzymatic activity. 20alpha-reduction of C21-steroids would represent an alternative pathway for their catabolism, not regulated by gonadotropin or not affected by estrogen, that would be significant in situations with reduced 17alpha-hydroxylase activity.


Fertility and Sterility | 1981

Varicocele and the morphology of spermatozoa.

Luis J. Rodriguez-Rigau; Keith D. Smith; Emil Steinberger

It is believed that varicocele is characteristically associated with specific abnormalities of spermatozoal morphology (increased numbers of tapered and amorphous forms). This report summarizes the results of a prospective study of spermatozoal morphology in 208 male partners of infertile couples seen consecutively during an 18-month period. After exclusion of 23 azoospermic males, sperm morphology in the remaining 56 patients with varicocele and 129 men without varicocele were compared. Although the incidence of abnormal spermatozoa was higher in patients with varicocele, no significant differences in the patterns of morphology were observed. In both groups of patients the percentage of normal spermatozoa was significantly correlated with the sperm count and with percentage motility. Sperm count and motility were significantly correlated with each other. The percentages of tapered and amorphous spermatozoa were inversely correlated with the motile sperm count. These results demonstrate that the pattern of spermatozoal morphology observed in men with varicocele is not characteristic or unique to this condition. It appears that abnormality of spermatozoal morphology is commonly associated with diminished sperm count and motility, regardless of the presence or absence of a varicocele.

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Emil Steinberger

Detroit Receiving Hospital

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Keith D. Smith

Albert Einstein Medical Center

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Robert K. Tcholakian

University of Texas at Austin

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David B. Weiss

Hebrew University of Jerusalem

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Zvi Zukerman

University of Texas at Austin

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Shahla Nader

University of Texas at Austin

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Ajit K. Chowdhury

University of Texas at Austin

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Carma Ayala

Centers for Disease Control and Prevention

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H. Edward Grotjan

University of Texas at Austin

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Steven M. Petak

University of Texas Health Science Center at Houston

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