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1.
PLoS One ; 14(11): e0220170, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31693666

RESUMO

There is great debate surrounding the demographic impact of China's population control policies, especially the one-birth restrictions, which ended only recently. We apply an objective, data-driven method to construct the total fertility rates and population size of a 'synthetic China', which is assumed to be not subjected to the two major population control policies implemented in the 1970s. We find that while the earlier, less restrictive 'later-longer-fewer' policy introduced in 1973 played a critical role in driving down the fertility rate, the role of the 'one-child policy' introduced in 1979 and its descendants was much less significant. According to our model, had China continued with the less restrictive policies that were implemented in 1973 and followed a standard development trajectory, the path of fertility transition and total population growth would have been statistically very similar to the pattern observed over the past three decades.


Assuntos
Política de Planejamento Familiar , Coeficiente de Natalidade/tendências , Criança , China , Demografia , Características da Família , Política de Planejamento Familiar/história , Política de Planejamento Familiar/legislação & jurisprudência , Política de Planejamento Familiar/tendências , Feminino , Fertilidade , História do Século XX , História do Século XXI , Humanos , Masculino , Modelos Teóricos , Controle da População/história , Controle da População/tendências , Dinâmica Populacional/tendências , Crescimento Demográfico , Gravidez , Política Pública , População Rural , Fatores Socioeconômicos , População Urbana
3.
Lancet ; 388(10054): 1930-1938, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27751400

RESUMO

In October, 2015, China's one-child policy was replaced by a universal two-child policy. The effects of the new policy are inevitably speculative, but predictions can be made based on recent trends. The population increase will be relatively small, peaking at 1·45 billion in 2029 (compared with a peak of 1·4 billion in 2023 if the one-child policy continued). The new policy will allow almost all Chinese people to have their preferred number of children. The benefits of the new policy include: a large reduction in abortions of unapproved pregnancies, virtual elimination of the problem of unregistered children, and a more normal sex ratio. All of these effects should improve health outcomes. Effects of the new policy on the shrinking workforce and rapid population ageing will not be evident for two decades. In the meantime, more sound policy actions are needed to meet the social, health, and care needs of the elderly population.


Assuntos
Coeficiente de Natalidade , Cuidadores , Emprego , Necessidades e Demandas de Serviços de Saúde/tendências , Filho Único , Controle da População , Crescimento Demográfico , Política Pública , Razão de Masculinidade , Saúde da Mulher , Aborto Induzido , Envelhecimento , China/epidemiologia , Coerção , Confucionismo , Anticoncepção/métodos , Pessoas com Deficiência/estatística & dados numéricos , Escolaridade , Etnicidade/legislação & jurisprudência , Feminino , Serviços de Saúde/tendências , Nível de Saúde , História do Século XX , História do Século XXI , Humanos , Renda , Dispositivos Intrauterinos/estatística & dados numéricos , Masculino , Pais , Controle da População/história , Controle da População/legislação & jurisprudência , Controle da População/tendências , Política Pública/história , Política Pública/legislação & jurisprudência , Política Pública/tendências , Punição , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos
5.
Sci Prog ; 98(Pt 4): 379-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26790176

RESUMO

Population growth makes food production increase necessary; economic growth increases demand for animal products and livestock feed. As further increase of the cropland area is ecologically undesirable, it is necessary to increase crop yields; this requires, inter alia, more nitrogen and phosphorus fertiliser despite the environmental problems which this will exacerbate. It is probable that a satisfactory food supply and an environmentally benign agriculture worldwide cannot be achieved without reducing population to approximately three billion. The reduction could be achieved by 2200 if the total fertility rate--currently 2.5--declined to 1.5 as a world average by 2050, and remained at that level until 2200, but the probability of such a global fertility trajectory is close to zero. It will also be necessary to replace fossil energy by nuclear and renewable energy in order to stabilise atmospheric carbon dioxide concentration, but the phase-out cannot be completed until the 22nd century, when the atmospheric concentration will be approximately 50% above the 2015 level of 400 ppm.


Assuntos
Conservação dos Recursos Naturais/tendências , Produtos Agrícolas/provisão & distribuição , Fertilizantes/provisão & distribuição , Abastecimento de Alimentos , Controle da População/tendências , Crescimento Demográfico , Animais , Pegada de Carbono , Produtos Agrícolas/crescimento & desenvolvimento , Humanos , Nitrogênio/provisão & distribuição , Fósforo/provisão & distribuição
6.
Stud Fam Plann ; 45(4): 493-509, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25469931

RESUMO

In November 2013, China announced reforms to its family planning policies whereby couples would be allowed to have a second child if either parent is an only child. The announcement garnered worldwide media coverage, and stimulated academic and popular discussion. We explore the context of the 2013 reforms, including the economic, demographic, and political motivations behind them, and speculate on their likely effect. Noting that the impact of the reforms on China's long-term demographic future is likely to be relatively slight, we consider why more radical reform may have been difficult to implement. We offer observations about possible future directions for Chinese family planning policies and explore the notion of "local pronatalism within nationally prescribed antinatalist limits" and how this suggests that an ideological shift within China's family planning apparatus may be plausible.


Assuntos
Demografia , Política de Planejamento Familiar , Controle da População , China , Demografia/estatística & dados numéricos , Demografia/tendências , Dissidências e Disputas , Previsões , Humanos , Política , Controle da População/métodos , Controle da População/tendências , Crescimento Demográfico
14.
Am J Reprod Immunol ; 66(1): 5-12, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21481057

RESUMO

This is a review of current status and future perspectives on the development of antisperm contraceptive vaccines (CV) and immunocontraceptives. The development of antisperm CV is an exciting proposition. There is a strong rationale and recent data indicating that this proposition can translate into reality. The search for novel sperm-specific antigens/genes, that can be used for CV, continues using various recent developing technologies. Various approaches of proteomics, genomics, reproductive biology, mucosal immunity and vaccinology and several novel technologies such as gene knockout technology, phage display technology, antibody engineering, differential display technique, subtractive hybridization, and hybridoma technology are being used to delineate sperm-specific antigens and construct CV. Various sperm antigens/genes have been delineated, cloned, and sequenced from various laboratories. Vaccination with these sperm antigens (recombinant/synthetic peptide/DNA) causes a reversible contraceptive effect in females and males of various animal species, by inducing a systemic and local antisperm antibody response. The efficacy is enhanced by combination vaccination, including peptides based on various sperm antigens. Several human novel scFv antibodies with unique complementarity-determining regions (CDRs), that react with specific well-defined fertility-related sperm antigens, have been synthesized. These human infertility-related antibodies may find application in the development of novel immunocontraceptives. Besides finding the novel sperm antigens, the present and future focus is on enhancing the immunogenicity, bioefficacy, and on obliterating the inter-individual variability of the immune response, and proceeding for primate and human clinical trials. Multi-epitope vaccines combining sperm proteins involved in various steps of fertilization cascade have been found to enhance the immunogenicity and bioefficacy of the contraceptive effect. The in vitro synthesis of infertility-related human scFv antibodies may provide unique once-a-month immunocontraceptives, the first of its kind, for human use. The multi-epitope CV and preformed engineered human antibodies of defined specificity may obliterate the concern related to inter-individual variability of the immune response.


Assuntos
Anticoncepção Imunológica/métodos , Anticoncepcionais/imunologia , Controle da População/métodos , Espermatozoides/imunologia , Vacinas Anticoncepcionais/imunologia , Vacinas Sintéticas/imunologia , Animais , Antígenos/imunologia , Clonagem Molecular , Regiões Determinantes de Complementaridade/imunologia , Anticoncepção Imunológica/tendências , Feminino , Fertilidade/efeitos dos fármacos , Fertilidade/imunologia , Humanos , Masculino , Camundongos , Controle da População/tendências , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/imunologia , Vacinas Anticoncepcionais/uso terapêutico , Vacinas Sintéticas/uso terapêutico
16.
Am J Reprod Immunol ; 66(1): 40-50, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21501279

RESUMO

Wildlife, free-ranging and captive, poses and causes serious population problems not unlike those encountered with human overpopulation. Traditional lethal control programs, however, are not always legal, wise, safe, or publicly acceptable; thus, alternative approaches are necessary. Immunocontraception of free-ranging wildlife has reached the management level, with success across a large variety of species. Thus far, the immunocontraceptive research and management applications emphasis have been centered on porcine zona pellucida and gonadotropin-releasing hormone vaccines. Contraceptive success has been achieved in more than 85 different wildlife species, at the level of both the individual animal and the population. At the population management level with free-ranging species, the primary focus has been on wild horses, urban deer, bison, and African elephants. The challenges in the development and application of vaccine-based wildlife contraceptives are diverse and include differences in efficacy across species, safety of vaccines during pregnancy, the development of novel delivery systems for wild and wary free-ranging animals, and the constraints of certain non-contraceptive effects, such as effects on behavior. Beyond the constraints imposed by the public and a host of regulatory concerns, there exists a real limitation for funding of well-designed programs that apply this type of fertility control.


Assuntos
Animais Selvagens/imunologia , Anticoncepção Imunológica/métodos , Anticoncepção Imunológica/veterinária , Fertilidade/efeitos dos fármacos , Controle da População/métodos , Resultado do Tratamento , Vacinas Anticoncepcionais/imunologia , Vacinas Sintéticas/imunologia , Animais , Antígenos/imunologia , Bovinos , Anticoncepção Imunológica/economia , Anticoncepção Imunológica/ética , Cervos/imunologia , Proteínas do Ovo/imunologia , Equidae/imunologia , Feminino , Hormônio Liberador de Gonadotropina/imunologia , Masculino , Glicoproteínas de Membrana/imunologia , Controle da População/economia , Controle da População/tendências , Receptores de Superfície Celular/imunologia , Especificidade da Espécie , Suínos/imunologia , Vacinação , Vacinas Anticoncepcionais/administração & dosagem , Vacinas Sintéticas/administração & dosagem , Zona Pelúcida/imunologia , Glicoproteínas da Zona Pelúcida
17.
Afr J Reprod Health ; 15(2): 31-44, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22590891

RESUMO

Zimbabwe does not feature much on the current debate of fertility transition in sub-Saharan Africa. This article is trying to fill this gap by analysing the ZDHS data. The total fertility rate of Zimbabwe was close to 7 births during independence in 1980. However, it has declined to 3.8 in 2006. This does not only show that fertility in Zimbabwe has been declining over the years, but it is one of the lowest in the region. The fertility trend observed is mainly explained by use of contraception. The contraceptive prevalence rate was 60 percent in 2006. It is noted that the contraceptive uptake has continued to increase even during the years when Zimbabwe was going through serious political, economic, social and health challenges. This is because the groundwork done on the family planning programme soon after independence put a solid foundation in motivating women to use contraception.


Assuntos
Coeficiente de Natalidade/tendências , Comportamento Contraceptivo , Anticoncepção , Serviços de Planejamento Familiar/organização & administração , Fertilidade , Controle da População , Comportamento Contraceptivo/psicologia , Comportamento Contraceptivo/estatística & dados numéricos , Comportamento Contraceptivo/tendências , Anticoncepcionais/uso terapêutico , Dispositivos Anticoncepcionais , Países em Desenvolvimento , Feminino , Humanos , Motivação , Controle da População/métodos , Controle da População/estatística & dados numéricos , Controle da População/tendências , Zimbábue
18.
Philos Trans R Soc Lond B Biol Sci ; 364(1532): 2991-3007, 2009 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-19770151

RESUMO

We use data from the Demographic and Health Surveys to examine the patterns of stall in fertility decline in four Eastern African countries. Contrary to patterns of fertility transition in Africa that cut across various socio-economic and geographical groups within countries, we find strong selectivity of fertility stall across different groups and regions in all four countries. In both Kenya and Tanzania where fertility decline has stalled at the national level, it continued to decline among the most educated women and in some regions. While fertility has remained at pre-transition level in Uganda over the past 20 years, there are signs of decline with specific groups of women (especially the most educated, urban and those in the Eastern region) taking the lead. For Zimbabwe, although fertility has continued to decline at the national level, stall is observed among women with less than secondary education and those in some of the regions. We link these intra-country variations to differential changes in socio-economic variables, family planning programme environment and reproductive behaviour models. The results suggest that declines in contraceptive use, increases in unmet need for family planning, increasing preferences for larger families, and increases in adolescent fertility were consistently associated with stalls in subgroup fertility across all four countries. These results are consistent with models that emphasize the role of declines in national and international commitments to family planning programmes in the premature stall in sub-Saharan fertility transition.


Assuntos
Coeficiente de Natalidade/tendências , Modelos Biológicos , Controle da População/tendências , Dinâmica Populacional , África Oriental , Demografia , Feminino , Humanos , Controle da População/métodos , Comportamento Reprodutivo/fisiologia , Fatores Socioeconômicos
19.
Int J Gynaecol Obstet ; 106(2): 148-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19539930

RESUMO

Reproductive rights continue to be under threat, even some 15 years after the landmark International Conference on Population and Development in Cairo declared the importance of a satisfying and safe sex life, the capability to have children, and the right to decide on the timing, number, and spacing. The right to choose whether and when to have children is at risk both from some who seek to increase birth rates through pronatalist policies and from some who seek a return to "population control" as a response to global climate change, environmental degradation, endemic poverty, global recession, and food shortages. This paper argues the success of the rights-based approach to family planning, reproductive health and health education, and outlines issues and policy responses related to low fertility. This is contrasted with the unmet need for family planning in the poorest countries. It calls for health providers to advocate for reproductive rights, affirming that the freedom of women to control their fertility is the basis for other essential freedoms.


Assuntos
Fertilidade , Política de Saúde/tendências , Direitos Sexuais e Reprodutivos/tendências , Comportamento Sexual , Países em Desenvolvimento , Serviços de Planejamento Familiar/tendências , Feminino , Educação em Saúde/tendências , Humanos , Controle da População/tendências , Gravidez , Medicina Reprodutiva/tendências , Direitos Sexuais e Reprodutivos/psicologia , Comportamento Sexual/psicologia , Direitos da Mulher/tendências
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