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Condoms from five manufacturers were subjected to controlled exposures of heat, humidity, and air and to different natural environments in five countries. Under aerobic conditions (condoms in permeable packages or unpackaged), stress properties declined. The relationship between rate of decline as a function of temperature was quadratic. Under oxygen-restricted conditions (foil-wrapped packages) at average storage temperatures of 30 degrees C and lower, strain properties declined with little or no significant change in stress properties. The effect is to cause condoms to become stiffer; high-breakage rates in use have been correlated with product stiffening. A new rationale for accelerated-aging tests to predict condom shelf stability is suggested, including a test to control the trend of condoms to stiffen. Silicone lubricant, impermeable packaging, and inclusion of antioxidants in the condom formulation can prevent or minimize aerobic breakdown of latex condoms. Specifying low-modulus condoms can prevent excessive stiffening.

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To reduce their dependency on donors or the international currency costs of essential health care products, developing countries are building or improving capability for local manufacturing or competitive international procurement. Through long-term strategic planning, public/private partnerships, collaboration with firms in industrialized nations, and farsighted donor policies, the capacity for alternative supply can be increased in stages from importation through local processing and packaging to full production and multiproduct enterprises.

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This paper provides a critical overview of several strategies and mechanisms that have been employed by the Program for Appropriate Technology in Health over the past decade to address the unmet needs for health technologies in the developing world. Partnerships between public and private-sector organizations are emphasized in order to share risks, encourage efficiency, and ensure the availability of priority products for health care in resource-poor settings. Incentives for the involvement of the commercial sector, the means to protect the interest of the public sector, and the role of bridging organizations are discussed in the light of the shifting goals of the public sector.

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Laboratory tests were conducted on condoms to examine the changes that occur over time in indicators of condom burst strength, and to determine the relationship between laboratory-assessed condom burst strength and breakage during use in a developing country setting. Three groups of unaged condoms purchased directly from the manufacturer were used: one group exposed to UV light for 10 hours; one group exposed for five hours; and one group unexposed. A sample of each of these groups was tested according to ISO condom air burst test protocols. The remaining condoms were individually packaged in coded polyethylene bags for shipment to the developing country study site. Also used in the study was a group of condoms that had been aged for over 40 months under field conditions in a tropical climate; a sample from this group was tested by the ISO air burst test protocol and the remainder distributed to the study site. One-hundred-thirty Indonesian urban males participated in the double-blind study. Volunteers were not relying on the condom for contraceptive purposes. Each volunteer was given one individually packaged untreated condom, one condom from each treatment group, and four condoms aged in the field. Study participants were instructed to return all used condoms. Each condom that was returned after use was examined for breakage, and the unbroken condoms were subjected to an air inflation test to determine volume and pressure at burst. A comparison of the air burst volume data for a sample of unused and used condoms from the same treatment group indicates that most of the condoms that broke during use had air burst volumes below 11 liters. Therefore, a significant downward shift in the burst strength distribution as measured in the laboratory is likely to result in an increased breakage rate during use. A Condom Deterioration Index calculated from regular periodic testing of stored condom stocks is a convenient and sensitive means of monitoring trends in the distribution and deterioration of condom strength.

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Adult male rats were exposed or sham-exposed to 60-Hz electric fields without spark discharges, ozone, or significant levels of other secondary variables. No effects were observed on body weights or plasma hormone levels after 30 days of exposure at an effective field strength of 68 kV/m. After 120 days of exposure (effective field strength = 64 kV/m, effects were inconsistent, with significant reductions in body weight and plasma levels of follicle-stimulating hormone and corticosterone occurring in one replicate experiment but not in the other. Plasma testosterone levels were significantly reduced after 120 days of exposure in one experiment, with a similar but not statistically significant reduction in a replicate experiment. Weanling rats, exposed or sham-exposed in electric fields with an effective field strength of 80 kV/m from 20 to 56 days of age, exhibited identical or closely similar growth trends in body and organ weights. Hormone levels in exposed and sham-exposed groups were also similar. However, there was an apparent phase shift between the two groups in the cyclic variations of concentrations of hormones at different stages of development, particularly with respect to follicle-stimulating hormone and corticosterone. We concluded that 60-Hz electric fields may bring about subtle changes in the endocrine system of rats, and that these changes may be related to alterations in episodic rhythms.

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The relationship between condom strength and failure during use was examined in six volunteers using artificially deteriorated condoms. Samples of each condom set exposed to ultraviolet light for three to eleven hours were tested for strength by air burst procedures. The remaining condoms were used by volunteers protected from pregnancy by other means. Burst pressure fell to 35% and burst volume to 17% of untreated levels after six hours of ultraviolet exposure. A maximum mean breakage rate during use of 30% was obtained at this time, although individuals experienced breakage rates up to 70% at this stage of deterioration. No failures occurred during use until condoms had deteriorated by more than 25%. Conclusions were: 1) that burst test parameters can effectively and sensitively measure changes in condom strength, 2) that condoms produced to western industrial standards carry a wide margin of strength over and above the minimum required for effective use, 3) that stored condoms should not necessarily be thrown out if they are uniform in strength but fall below original acceptance standards.

PIP: The relationship between condom strength and failure during use was examined in 6 volunteers using artificially deteriorated condoms. Samples of each condom set exposed to ultraviolet light for 3-11 hours were tested for strength by airburst procedures. The remaining ones were used by volunteers protected from pregnancy by other means. Burst pressure fell to 35% and burst volume to 17% of untreated levels after 6 hours of ultraviolet exposure. A maximum mean breakage rate during use of 30% was obtained at this stage of deterioration. No failures occurred during use until condoms had deteriorated by more than 25%. Conclusions were: 1) that burst test parameters can effectively and sensitively measure changes in condom strength; 2) that condoms produced to western industrial standards carry a wide margin of strength over and above the minimum required for effective use; and 3) that stored condoms need not be thrown out if they are uniform in strength but fall below original acceptance standards.

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The inadvertent failure to achieve sterility in 8 to 40 vasectomy procedures afforded a rare opportunity to study the efficacy of placing the two cut ends of the vasa in different fascial planes. Interposition of the fascia was performed in 12 patients and was not performed in 28 others, with no significant difference in the failure rates of the two groups. Histologic examination of vasal tissue from one patient in each group revealed that a sperm granuloma can erode fascia and the wall of the vas.

PIP: In a series of 40 vasectomy patients, the procedures were performed through double vertical scrotal incisions. The vasa were separated from their sheaths and transected, but no part of the vas was removed. In 12 of the procedures, interposition of the fascia was performed and in the other 28, it was not. It has been felt that this interposition procedure created an impenetrable wall of fascia, preventing spontaneous anastomosis. The failure rate in this particular series was 21.4% for the patients in whom fascia was not interposed between the 2 cut ends of the vas; the failure rate for the 12 in whom fascia was interposed was 16.7%. There is no statistical difference in the failure rates for the 2 procedures. Thus, the interposition procedure does not seem to reduce the possibility of failure. Histologic examination of vasal tissue was made in 2 cases at the time of repeat vasectomy. 1 of these patients had undergone each of the 2 procedures. Microscopic pictures of the 2 cases are presented. The histologic examination showed that sperm granulomas can erode the fascia and the wall of the vas.

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A battery-powered, bipolar electrocoagulator has been specifically developed for sealing the cut ends of the divided vas at vasectomy. With a minimum of electric power, the electrocoagulator destroys only the mucosa and one or two muscle cell layers of the vas, which leads to optimal fibrosis of the cut ends. This instrument has been used in more than 1000 vasectomies without a known failure and with a minimum of complications. An analysis of these cases is reported with emphasis upon the method's success in sealing the vas.

PIP: Experience with the bipolar needle in the 1st 1000 cases is reported. All vasa were electrocoagulated with the battery-powered, bipolar electrocoagulator under local anesthesia in the office. This instrument requires a minimum of electric power and destroys only the mucosa and 1 or 2 muscle cell layers. The patients ranged in ages between 20 and 68 (82.5% were between the ages of 20 and 40). The number of living children whom these men had fathered ranged from 0 to 9 (53.2% had 2 children and 9.4% had 4 or more). The analysis confirms the statement that the electrocoagulation, fascial interposition technique has never failed in the author's hands. When the results are compared with ligation and monopolar techniques, the figures cited for wound infection, hematomas, and congestive epididymitis are so similar that they prove the only difference is in the type of cautery used. The low incidence of granulomas (.4%) indicated that the bipolar needle is an effective instrument for sealing the cut vas without ligatures, clips, or other devices.

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Whether antisperm antibodies develop after vasectomy probably depends on several variables, 1 of which may be the surgical technique. The levels of serum antisperm antibodies were compared in men vasectomized by 1 techniques: vasoligation and fulguration. No difference in the incidence of spermagglutinating antibody was found in the 2 groups. However, immobilizing antibodies were observed in 43 per cent of the men undergoing vasoligation but in only 29 per cent of the men vasectomized by fulguration.

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The dynamics of venous-arterial testosterone transfer in the pampiniform plexus of the rat have been studied using [3-H] testosterone in controlled perfusion in the pampiniform plexus isolated from its testicle in vivo. The rate of transfer of testosterone increased in direct proportion to the testosterone concentration in spermatic vein blood over the range 0-100 ng/ml. When the venous-arterial concentration gradient was reversed by infusing [14-C] testosterone into the spermatic artery proximal to the pampiniform plexus, the label was transferred from the artery to the adjacent spermatic vein. Transfer of [3-H] methoxy-inulin infused concomitantly with the [14-C] testosterone was relatively insignificant in either direction. The testosterone transfer rate generally increased with increasing blood flow over the range 0.01-0.36 ml/min. However, transfer rate became less dependent on blood flow at the high end of the range. A comparison of transfer rates from whole blood and dextran (6% in saline) each containing 24-27 ng [1,2-3-H] testosterone/ml and flowing at 0.36 ml/min for one hour resulted in a maximum of 6.1% transfer from blood and 46% transfer from dextran. Transfer from blood reached plateau levels in less than 10 min, whereas transfers from dextran peaked between 30 and 40 min. At lower rates testosterone transfer from dextran reached equilibration levels, whereas transfer from blood rarely exceeded 5% of spermatic venous levels. We concluded that venous-arterial steroid transfer in the pampiniform plexus behaves like a passive countercurrent diffusion system that is concentration limited, depending principally on the concentration gradient of diffusible steroid between the closely juxtaposed spermatic vein and artery.

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