Genetic influence on age at first birth of female twins born in the UK, 1919–68

Using a sample of monozygotic (945, 42?per cent) and dizygotic (1,329, 58?per cent) twin pairs born 1919–68 in the UK, we applied innovative tobit models to investigate genetic and environmental influences on age at first birth (AFB). We found that a substantial part (40?per cent) of the variation in AFB is caused by latent family characteristics. Genetic dispositions (26?per cent) play a more important role than the shared environment of siblings (14?per cent), with the non-shared environment/measurement error having the strongest influence (60?per cent). Like previous studies, this study reveals marked changes in estimates over time, and supports the idea that environmental constraints (war or economic crisis) suppress and normative freedom (sexual revolution) promotes the activation of genetic predispositions that affect fertility. We show that the exclusion of censored information (i.e., on the childless) by previous studies biased their results.

Supplementary material for this article is available at: http://dx.doi.org/10.1080/00324728.2015.1056823     

The effects of child-related benefits and pensions on fertility by birth order: A test on Hungarian data

Using aggregate time-series data from post-war Hungary, we investigated the effect of child-related benefits and pensions on overall fertility and fertility by birth order. The results indicate moderate effects that are robust across a wide range of specifications. According to our estimates, a 1-per-cent increase in child-related benefits would increase total fertility by 0.2 per cent, while the same increase in pensions would decrease fertility by 0.2 per cent. The magnitude of both effects increases by birth order; this is more robust for child-related benefits.     

Worldwide fertility declines do not rely on stopping at ideal parities

A key demographic hypothesis has been that fertility declines rely on stopping at target parities, but emerging evidence suggests that women frequently reduce fertility without specific numeric targets. To assess the relative importance of these two paths to fertility decline, we develop a novel mixture model to estimate: (1) the proportion of women who stop at a target parity; and (2) mean completed fertility among those who do not. Applied to Demographic and Health Survey data from women aged 45–49 in 84 low- and middle-income countries, and to United States Census cohorts, the model shows considerable variation in the proportion stopping at specific parities (1–84?per cent). The estimates also show that declines in completed fertility are largely attributable to women who do not stop at target parities, suggesting that stopping at ideal parities may be less important than parity-independent decisions for a wide range of fertility transitions.     

Fertility in Kenya and Uganda: A comparative study of trends and determinants

Between 1980 and 2000 total fertility in Kenya fell by about 40 per cent, from some eight births per woman to around five. During the same period, fertility in Uganda declined by less than 10 per cent. An analysis of the proximate determinants shows that the difference was due primarily to greater contraceptive use in Kenya, though in Uganda there was also a reduction in pathological sterility. The Demographic and Health Surveys show that women in Kenya wanted fewer children than those in Uganda, but that in Uganda there was also a greater unmet need for contraception. We suggest that these differences may be attributed, in part at least, first, to the divergent paths of economic development followed by the two countries after Independence; and, second, to the Kenya Government's active promotion of family planning through the health services, which the Uganda Government did not promote until 1995.     

Buddhist factors in population growth and control A survey based on Thailand and Ceylon *

Abstract Although Buddist doctrine and institutions do not directly encourage the procreation of children, the Buddhist countries of South Asia (for the purposes of this paper, Ceylon, Burma, Thailand and Cambodia) have high fertility rates. The first half of this paper is devoted to examining possible reasons for this: particularly, whether there are non-Buddhist factors which produce high fertility and outweigh the negative Buddhist attitude, or whether there are less obvious factors within the structure of Buddhist culture which tend to produce high fertility indirectly; this preliminary review of evidence favours the latter explanation. In the second half of the paper South Asian Buddhist attitudes to policies of population control are examined. While in theory there is no Buddhist opposition to family planning, apart from the general Buddhist rejection of abortion, some differences of attitude towards other methods are observable between Ceylon and Thailand, the Buddhist opposition to contraception being stronger in the former than in the latter. It is suggested that the differences in attitude may be due to the larger proportion of non-Buddhists in the population of Ceylon than in Thailand, although the opposition is expressed in primarily doctrinal terms.     

Below-replacement fertility: Determinants and prospects in South Asia

Although 10 countries and two of China’s special administrative areas, totalling 1,528 million people or 44 per cent of Asia’s total population, are now characterized by fertility rates below long-term replacement levels, no such countries are yet found in South Asia. This paper first examines the characteristics of 12 Asian administrations with very low fertility at various stages of their fertility declines and then compares the findings with the present situation in three South Asian countries, Sri Lanka, India and Bangladesh. This allows a prediction of when the South Asian countries will reach replacement fertility in accord with the trends in two key criteria, the percentage of girls in secondary school and the infant mortality rate. These conclusions are then buttressed for each country by the findings of anthropological demographic research programs in which the authors were involved. The predictions are that all three countries will attain a total fertility rate of 2.1 within the next 30 years and that the UN2000 Revision of the medium population projection is plausible in that regard. However, the authors part company with the UN projection in their assessment that the nature of these societies means that they will all subsequently fall to still lower fertility levels.     

Projecting future utilization of medically assisted fertility treatments

This study estimates the future utilization of medically assisted fertility treatments in Australia, focusing on assisted reproductive technologies (ARTs), intrauterine insemination (IUI), and ovulation induction. A multistate cohort component population projection model is used to determine future fertility rates from 2016 to 2026 by age and education level. These are combined with information on recent trends in use and success rates to indirectly estimate future age-specific probabilities of fertility treatment utilization. The number of ART cycles is expected to increase by 61 per cent between 2016 and 2026 if treatment success rates remain at 2015 levels, or by 34 per cent if recent improvements in ART success rates continue. The model also predicts that numbers of IUI cycles and ovulation induction cycles will decrease by 17 and 3 per cent, respectively. This research confirms the importance of including both technological improvements and socio-demographic changes when predicting future fertility treatment utilization.     

Below-replacement fertility in Thailand and its policy implications

The fertility transition in Thailand has been one of the most rapid among Asian countries that are yet to attain newly industrialized country status. In the early 1960s, the total fertility rate exceeded six births per woman; currently, it stands at 1.9 or slightly below replacement level. At present, it is hard to predict the future trend in fertility as this involves several factors that need much closer study, in particular, fertility preferences, changes in marriage patterns and the wider effects of the current economic crisis in Thailand. Rapid declines in fertility and mortality have had a profound effect on the age structure of the population, notably the increasing elderly proportion. Thailand now faces new challenges and priorities for population policy. Policy responses to concerns arising from below-replacement fertility will be much more complex and involve greater government activism, improved institutional capacities and more resources than in the past. This paper reviews the fertility transition in Thailand and looks at some consequences and policy implications of low fertility, with special reference to the family and the elderly population. National Statistical Office     

Fertility intentions and maternal health behaviour during and after pregnancy

This study examines associations between fertility intentions and maternal health behaviours during and after pregnancy among a nationally representative sample of 3,442 women from India. Two waves of data (2005, 2012) from the India Human Development Survey were analyzed to investigate the influence of unwanted births on women’s use of antenatal care, timely postnatal care, and the delivery setting using binary and ordered logistic regression, partial proportional odds models, and propensity score weighting. Fifty-eight per cent of sample births were unwanted. Regression results show that, net of maternal and household characteristics, women with unwanted births were less likely to obtain any antenatal care and had fewer antenatal tests performed. Unwantedness was also associated with a lower likelihood of delivering in an institutional setting and of obtaining timely postnatal care. The relationships between unwantedness and antenatal care, postnatal care, and delivery setting were robust to models accounting for propensity weighting.     

应用队列累计生育率分析我国生育水平变动趋势——兼与郭志刚教授讨论

本文对反映生育水平的两个基本指标——总和生育率和队列累计生育率进行分析,肯定多年来多个调查所得到的队列累计生育率的数据质量。尽管队列累计生育率反映的是"过去"而不是"当前"的实际生育水平,但历次调查所反映出的1990年代以来生育水平变化趋势是持续下降,并推断近几年的总和生育率已经下降到1.6以下。     

生育转型、性别平等与香港生育政策选择

香港是世界上生育率水平最低的超低生育率地区之一。低生育率现象是个体导向的社会机制所倡导的两性平等与家庭导向的社会机制在事实上的性别不平等之间强烈冲突的结果。“有偿养育计划”也许是刺激那些有多生倾向的家庭把生育意愿转变为实际生育行为的有效途径。     

用孩次递进比模拟“全面二孩”政策调整初期的生育行为--以湖北省为例

以2014年湖北省卫生和计划生育委员会提供的包括“单独”、“双独”方面的数据为基础，描述了生育政策调整下被压抑的生育潜能释放的规律性和用孩次递进比的方法预测“全面二孩”政策调整初期的生育行为，与意愿分析方法相互比照，丰富了当下生育政策下生育行为预测研究。从分析结果可以看出，假定2016年“全面二孩”生育政策调整，湖北省第一年内会新增二孩出生量52621人，占湖北省2014年总出生量的7?41％；三年内最低会新增139262人的二孩生育量。城乡对比发现，农村新增二孩生育占到将近六成，且由抢生而导致的堆积主要集中在农村，40岁后的高龄抢生情况不严重。     

我国生育意愿及其影响因素研究综述：1980～2015

2016年1月1日起实施的全面二孩政策能否有效地鼓励民众的生育行为，这关乎到我国未来几十年合理调整人口结构、稳固新常态发展的成功与否。本文通过对我国1980-2015年有关生育意愿的国内外文献总结回顾，将生育意愿的内涵界定为数量、时间、性别、动机四个维度，并在此基础上结合国内外学者们的研究归纳得出影响生育意愿的五个方面因素：政策、经济、观念、教育、年龄，以期在新政策背景下展望未来，借鉴国外发展的经验，做好养老、医疗、就业、教育方面的准备措施来迎接全面二孩时代，并为有关生育意愿的进一步研究提供参考。     

Case study: fertility decline in Iran

Iran has experienced one of the most successful family planning programs in the developing world, with 64 percent decline in total fertility rate (TFR) between 1986 and 2000. This paper focuses on Iranians’ unique experience with implementation of a national family planning program. Recognition of sensitive moral and ethical aspects of population issues resulted in successful collaboration of technical experts and religious leaders. Involvement of local health workers, women health volunteers and rural midwives led to great community participation. Demographic and Health Survey (DHS) data in 2000 indicated a TFR of 2.0 births per women and 74 percent contraceptive use among married women. This case study will help policy makers and researchers in Moslem countries and other developing countries with high fertility rate to consider a successful family program as a realistic concept with positive impacts on nation’s health and human development.     

Translation Formulae for Non-repeatable Events

China's one-per-hundred population survey, conducted in mid-1987, provides the first nation-level data with which to study recent fertility change in China. Using a recently developed extension of the ‘own-children’ method of fertility estimation, period parity progression ratios are computed from the survey data. Comparison with similar statistics computed from the 1982 one-per-thousand fertility survey provides a rigorous check on the quality of the results. The level of fertility so measured rose by 13 per cent between 1985 and 1987, compared with an increase of eight per cent in conventional total fertility ratios. Nearly 90 per cent of the increase was due to rising levels of progression from first to second birth. There can be little doubt that this, in turn, was due to a relaxation in the one-child family policy. Overall levels of progression to births of higher orders have been declining since 1982, but the evidence suggests that this is so only because of stringent government efforts to control births of third and higher orders.     

The demography of words: The global decline in non-numeric fertility preferences, 1993–2011

This paper examines the decline in non-numeric responses to questions about fertility preferences among women in the developing world. These types of response—such as ‘don’t know’ or ‘it’s up to God’—have often been interpreted through the lens of fertility transition theory as an indication that reproduction has not yet entered women’s ‘calculus of conscious choice’. However, this has yet to be investigated cross-nationally and over time. Using 19?years of data from 32 countries, we find that non-numeric fertility preferences decline most substantially in the early stages of a country’s fertility transition. Using country-specific and multilevel models, we explore the individual- and contextual-level characteristics associated with women’s likelihood of providing a non-numeric response to questions about their fertility preferences. Non-numeric fertility preferences are influenced by a host of social factors, with educational attainment and knowledge of contraception being the most robust and consistent predictors.     

独生子女比例、婚育意愿变动对未来政策生育率的影响

苏州市是我国计划生育政策执行得最早、最严格的地区之一,也是我国经济最为发达的地区之一.目前苏州市第一代独生子女大规模进入婚育年龄,使得政策生育率自然升高,同时经济的迅猛发展使得独生子女的婚姻观念发生深刻的变化.本文试探将婚育人口独生子女比例、婚育意愿等因素纳入预测模型,以期使得预测方法和结论更加准确.文章认为,未来15年苏州政策生育率上升0.415,而考虑婚育意愿后,现实的生育率上升仅0.23,终身生育率仍在1.5个以下,人口再生产将长期处于低生育水平.     

Where have all the children gone? Women's reports of more childlessness at older ages than when they were younger in a large-scale continuous household survey in Britain

Levels of childlessness reported by the same cohorts of women and surveyed by the British General Household Survey increase with age by over 50 per cent between their early 40s and their late 50s for women born in the early 1940s. Yet the reported mean fertility of parous women remains constant with increasing age. Similar results hold within sub-groups such as different educational and marital status groups. Possible reasons for these findings include declining comparability of the base population over time due to differential migration, mortality, or institutionalization, changes in survey design and content, and differential non-response by childless and parous women. The evidence shows that these are not adequate explanations. The most likely reason is deliberate under-reporting of childbearing among older cohorts of women. The findings have implications for the interpretation of retrospective data in surveys and for the availability of informal care for older people.     

Making Comparisons of Demographic Aggregates more Meaningful: A Case of Life Expectancies and Total Fertility Rates

With the recent emphasis on human development, development researchers are making frequent use of aggregate demographic measures in describing development experiences and more so while linking health and development. And it is often seen that comparison of these demographic aggregates across space and time is naïve given their complex construct on one hand and the implied meaning on the other. Are these comparisons across the board valid for the meanings ascribed to them? Or are the stated achievements as well as projected trends based on them reliable? This paper attempts to illustrate these concerns taking the twin aggregate measures frequently in use namely the life expectancy and Total fertility Rates. The primary focus here has been to link additional dimension of the same phenomenon (referring to survival or fertility here) which does not follow the principle of matched ordering while read along with these aggregates. Taking into account these additional dimensions, the magnitude of the differences in these aggregate measures gets moderated and their comparison across levels (between lower and higher) becomes more consistent.     

Cholera epidemics and their control in Ceylon

Summary Although cholera was never endemic in Ceylon, the country was subject to frequent (and in many instances explosive) cholera epidemics, due to its many contacts with the Indian sub-continent, the source where the disease was endemic. The frequency of epidemics was caused by the heavy movement of Indian labour working on the plantations of Ceylon between the two countries. This study charts the course of cholera in Ceylon beginning in the nineteenth century and seeks to identify the causes which led to its decline. Although there has always been doubt regarding the efficacy of quarantine in controlling cholera, its history in Ceylon indicates that whatever the drawbacks, quarantine was one of the major factors leading to the decline of this disease in the country. In addition, one of the essential elements in the battle against cholera in Ceylon was the development of a public health department which had the capacity to restrict the spread of an epidemic. This was done by the timely enforcement of various public health measures when the disease escaped the quarantine net. This survey also indicates that in the case of Ceylon, medical treatment and hospitalization was of no significance in controlling the number of deaths among those who contracted cholera, since all the great cholera epidemics occurred before treatment by intravenous re-hydration was introduced.