The Growth of World Population Analysis of the Problems and Recommendations for Research and Training (1963) / Chapter Skim
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Bio-Medical Factors
Bio-Medical Factors
Pages 28-36
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From page 28... ...
The diverse needs among people throughout the world require development of a variety of methods and procedures. Some effective methods of preventing reproduction are unacceptable-methods that remove or destroy the organs (testes or ovaries)
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From page 29... ...
A major drawback of most of these methods, of course, is that they are too closely related to the sexual act itself; for that and other reasons they may not provide sufficient effectiveness for the large majority of people in the world. For the majority we need simpler and less-demanding methods than are now available-methods consonant with weak motivation, inferior educational attainment, ignorance of biological processes, and other cultural differences.
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From page 30... ...
implantation of the blastocyst in the endometrium, and maintenance of continuing embryonic development. Attention is now being given to each of these steps by investigators, but accelerated and expanded effort is essential if we expect to devise a sufficient variety of regulatory methods quickly enough to affect significantly the world's population growth rate.
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From page 31... ...
The oral ingestion of these agents for 20 days, beginning on the fifth day of the menstrual cycle, will effectively abolish the normal ovulatory cycle and substitute an artificial anovulatory cycle- one in which no eggs are released from the ovary. It is estimated that almost two million women in the United States now use oral contraceptives as their only means of regulating fertility, and it is likely that at least another two million are doing so in other parts of the world.
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From page 32... ...
If so, they will have certain important advantages over the oral contraceptives presently available. Antispermatogenic agents It has been known for approximately ten years that certain compounds of the nitrofuran and thiophene type are capable of inhibiting spermatogenesis in animals by halting this process at the primary spermatocyte stage, one of the early stages in the formation of mature sperm.
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From page 33... ...
These observations, secured in two separate groups of volunteer institutionalized individuals, were sufficiently encouraging to suggest clinical studies on the contraceptive effectiveness of these compounds. When the trials were made, however, an unexpected side-effect quickly became manifest: Individuals ingesting the drugs experienced exaggerated responses to the peripheral effects of alcohol, which, though not serious, were unpleasant enough to suggest that general acceptance of this form of contraception would be unlikely.
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From page 34... ...
Some of these can be inserted into the uterine lumen without dilation of the cervix, thus facilitating their use. The record for effectiveness and acceptability of each of these devices appears to be exceptionally goorI; several thousand women are currently using one or another of these devices in experimental programs under careful clinical supervision.
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From page 35... ...
In the mate, active immunization using testicular vaccines is known to prevent sperm development. The formed antibodies destroy and prevent further formation of sperm cells for extended periods of time.
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From page 36... ...
This latter type of regulation would be not only effective but also, in all likelihood, widely acceptable. There are numerous other possibilities for the application of immunologic principles to the control of fertility, and it is reasonable to anticipate the development of various methods of inhibiting fertility by induction of antibodies against substances involved in specific reproductive processes.
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