Reproductive health and AIDS prevention in sub-Saharan Africa: the case for increased male participation.
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Reproduction is a dual commitment, but so often in much of the world, it is seen as wholly the woman's responsibility. She bears the burden not only of pregnancy and childbirth but also the threats from excessive child bearing, some responsibility for contraception, infertility investigation and often undiagnosed sexually transmitted diseases (STDs) including AIDS. Failure to target men in reproductive health interventions has weakened the impact of reproductive health care programmes. The paper proposes that sophisticated and dynamic strategies in Africa and elsewhere which target women's reproductive health and research (such as control of STDs including AIDS, family planning, infertility investigation) require complementary linkage to the study and education of men. Men's perceptions, as well as determinants of sexual behavioural change and the socioeconomic context in which STDs, including AIDS, become rife, should be reviewed. There is a need to study and foster change to reduce or prevent poor reproductive health outcomes; to identify behaviours which could be adversely affecting women's reproductive health. Issues of gender, identity and tolerance as expressed through sexuality and procreation need to be amplified in the context of present risks in reproductive health. Researchers and providers often ignore the social significance of men. This paper reviews the impact of male dominance, as manifested through reproductive health and sexual decisions, against the background of present reproductive health problems. A research agenda should define factors at both macro and micro levels that interact to adversely impinge on reproductive health outcomes. This should be followed up by well-developed causal models of the determinants of positive reproductive health-promoting behaviours. Behaviour specific influences in sexual partnership include the degree of interpersonal support towards prevention, for example, of STDs, unwanted pregnancy or maternal deaths. Perceived efficacy and situational variables influencing male compliance in, say, condom use, form part of the wider study that addresses men. Thus preventive reproductive health initiatives and information should move from the female alone to both sexes. Women need men as partners in reproductive health who understand the risks they might be exposed to and strategies for their prevention. (+info)
Effect of intravasal copper on the fertility of rats.
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Copper wire was inserted into the vas deferens and its effect of the reproductive system and fertility performance of rats was investigated. The copper wire was 100% effective as a contraceptive for up to 4 months if placed correctly, and resulted in decapitation of most of the spermatozoa. No differences between the rats with an intravasal copper wire and the sham-operated controls were found for the weights of the gonads and accessory sex glands or for protein, RNA, DNA and fructose concentrations. The intravasal copper device appears to be promising for the development of a long-term method for male contraception. (+info)
Recent biochemical approaches to post-testicular, epididymal contraception.
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Results from recent animal models with implications for putative human male contraceptives acting on the epididymis are reviewed. Inducing sterility by enhancing sperm transport through the epididymis has not been achieved. The induction of infertility in males of several species is easier to achieve by direct actions of drugs on sperm function (e.g. inhibition of sperm-specific isoenzymes of the glycolytic pathway by chloro-compounds) than by indirectly reducing amounts of epididymal secretions normally present in high concentration (e.g. alpha-glucosidase, L-carnitine). The former show promise for the clinic since human spermatozoa are susceptible to inhibition. On the other hand, the infertile male mice of the c-ros knock-out model demonstrate the influence of even a small region of the epididymis on fertility, so that targeting the as yet unknown epididymal factors presumably secreted in limiting amounts by this epididymal segment, is a new lead for a contraceptive. Targeting a specific sperm protein acquired in the testis, but depleted in the epididymis by toxicants that induce rapid infertility, may also lead to the discovery of new contraceptives, but these will require developing new means of organ-specific delivery of contraceptive drugs. (+info)
Chronic toxicity and reversibility of antifertility effect of immunization against gonadotropin-releasing hormone in male rats and rabbits.
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The chronic systemic toxicity of immunization with gonadotropin-releasing hormone, conjugated to tetanus toxoid (GnRH-TT), was investigated in male rats and rabbits in order to start Phase I clinical trials. Groups of rats and rabbits were immunized with GnRH-TT dissolved in aqueous adjuvant. The antigen was administered at weeks 0, 4, and 8, followed by boosters to maintain high antibody titers. At termination (8-9 months after first immunization), twenty rats and ten rabbits exhibiting the highest mean anti-GnRH titers and all the controls were selected for complete toxicological evaluation. In the rat study, a castrated control group was included for comparison with the immunized group. The hematological and serum chemistry parameters of immunized rats and rabbits were not affected in a significant manner. Most of the changes in serum chemistry of immunized rats were also found in castrated rats, indicating that the changes are most likely due to the withdrawal of androgenic support. The weights of the testes, epididymides, and sex accessory glands were lower in all immunized animals. There was significant atrophy of the germinal epithelium, which, however, sustained a population of Sertoli cells, spermatogonia, and pachytene spermatocytes. Other morphological changes in the prostate, seminal vesicles, pituitary, and mammary gland reflected the effect of androgen withdrawal. The decrease in the weight of liver, kidney, and heart seen in the immunized rats was also present in castrated rats and was not associated with any histopathological changes. The reversibility of immunization-induced infertility was investigated by mating the rats with normal females. Four months after the start of immunization, 9 out of 10 immunized rats were infertile whereas by nine months, all rats had regained fertility. Thus, it is concluded that immunization with GnRH-TT had no systemic toxicological effects in the adult male rats and rabbits for the period studied. The results also indicated that the GnRH-TT immunization had an antifertility effect in male rats. Fertility was restored following cessation of immunization and decline in anti-GnRH antibody titers. (+info)
Potential impact of hormonal male contraception: cross-cultural implications for development of novel preparations.
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The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available. (+info)
Would women trust their partners to use a male pill?
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Despite a renewed interest in the development of hormonal contraceptives for men, many discussions about the potential acceptability of a 'male pill' end by speculating whether women would trust their partners to use the method reliably. To determine the views of women, we undertook a survey of 1894 women attending family planning clinics in Scotland (450), China (900) and South Africa (544). In all centres over 65% of women thought that the responsibility for contraception falls too much on women. More than 90% in South Africa and Scotland thought that a 'male pill' was a good idea, with Chinese women (71% in Hong Kong and 87% in Shanghai) only slightly less positive. Only 13% of the total sample did not think that hormonal male contraception was a good idea and only 36 women (2% of the total) said that they would not trust their partner to use it. 78% of Scottish women, 71% of Shanghai women, and 78% of white women and 40% of black and coloured women in Cape Town thought that they would use the method. This survey should dispel the myth that women would not trust their partners to use a 'male pill' reliably and illustrates the potential market for the method. (+info)
Oestradiol enhances testosterone-induced suppression of human spermatogenesis.
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The aim of this study was to determine for the first time in humans, the efficacy of adding a low dose oestradiol to a suboptimally suppressive testosterone dose in a depot hormonal regimen to suppress spermatogenesis in healthy eugonadal men. Twenty-six healthy men were randomized into groups that were treated by a single subdermal implantation of either 600 mg testosterone alone (T; n = 11) or together with 10 mg (TE10, n = 7) or 20 mg (TE20, n = 8) oestradiol. Administration of oestradiol produced a dose-dependent increase in peak plasma oestradiol at 1 month and prolonged suppression of plasma LH and FSH leading to significantly enhanced suppression of sperm output. Despite the augmented spermatogenic suppression, there was no significant difference in the proportions achieving azoospermia (6/26, 23%) or severe oligozoospermia (<1 or <3 x 10(6) spermatozoa per ml, 7/26, 27%) and overall these proportions were inadequate to provide reliable contraception according to the standards identified in World Health Organization male contraceptive efficacy studies. Total and free testosterone remained within the eugonadal reference range for young men throughout the study. While the lower oestradiol dosage had minimal spermatogenic suppression effects, the higher dose produced dose-limiting adverse effects of androgen deficiency and/or oestrogen excess between the fourth and sixth month of the study. This appeared to be due to the unexpectedly prolonged, low concentration of oestradiol release from the oestradiol implants. There were no significant treatment-related changes in body composition, lipids, prostate-specific antigen, haematological or biochemical variables. Thus oestradiol has a low therapeutic window and dose-limiting side-effects at dosages that fail to achieve the uniform azoospermia required of an effective male hormonal contraceptive regimen. (+info)
Effects of sulphapyridine on sperm transport through the rat epididymis and contractility of the epididymal duct.
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This study was undertaken to investigate the effects of sulphapyridine on the transport of spermatozoa through different regions of the epididymis and on the contractility of the epididymal duct in the rat. Sperm transport was investigated by labelling testicular spermatozoa with [3H]thymidine and measuring intraluminal pressures of the epididymis by micropuncture, using a servo-nulling pressure transducer system. In control rats, the transit times of epididymal spermatozoa from the initial segment to the caput, from the caput to the proximal cauda, and from the proximal cauda to the distal cauda were 2, 6 and 3 days, respectively, giving a total transit time of 11 days. The total transit time was shortened to 8 days after treatment with sulphapyridine at a dosage of 450 mg kg-1 for 38-52 days. The rate of sperm transport was most affected in the caput epididymidis. Measurements of intraluminal pressures showed that sulphapyridine had no effect on spontaneous contractions in any regions of the epididymis. However, the frequency of contraction of the corpus and cauda epididymides in response to administration of 10 micrograms noradrenaline kg-1 in the sulphapyridine-treated rats was significantly higher (P < 0.05) than it was in the controls. Methacholine, at a dose of 20 micrograms kg-1, produced a smaller increase in basal pressure in the caput epididymidis of sulphapyridine-treated rats (P < 0.05) compared with controls. The results led to the conclusion that sulphapyridine increases the rate of sperm transport from the caput through the cauda epididymidis, in part, by changes in the responsiveness of the epididymis to the autonomic nervous system. (+info)