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1.
Summary The 1973 U.S. National Survey of Family Growth is used to examine the effects of removing number and timing failures from the reproductive histories of various cohorts of white and black married women. Blacks are more fertile than whites primarily because of their greater unwanted fertility. Removing number and timing failures from the past reproductive histories of American women would have reduced their fertility considerably. These reductions would have been greater for blacks than for whites and would be greater if some wanted pregnancies had continued to terminate in foetal loss.  相似文献   

2.
Social differentials in cumulative fertility revealed by field surveys in a number of countries typically have been interpreted with the implicit assumption that the timing of childbearing within the reproductive period remains constant. However, the reproductive histories that have been collected in such surveys provide a largely unexploited source of data for the analysis of trends in timing. An analysis by birth cohort of the fertility experience of 592 ever-married women surveyed in San Juan, Puerto Rico, in 1966 shows that significant changes in timing have occurred. Women in the more recent birth cohorts are distinguished by earlier childbearing and sustained higher fertility in consecutive age periods. The inter-cohort differences remain when adjustments are made for duration of time in legal and consensual unions.  相似文献   

3.
Ryder NB  Westoff CF 《Demography》1969,6(4):435-444
Data concerning the planning circumstances of the interval preceding each pregnancy, collected from a national sample of 4810 married women, are used to establish the fertility planning status of each respondent as one of five classes: (1) never-pregnant; (2) number failure; (3) at least one timing failure; (4) at least one timing success; (5) neither success nor failure. For the ever-pregnant women who intended no more children, 32 percent of the exposed were number failures and 62 percent of the rest were timing failures. For the ever-pregnant women who intended more children, 67 percent of the exposed were timing failures. Women not exposed to the risk of timing failure because they claimed to want all of their pregnancies as soon as possible had similar characteristics to women reporting failures; accordingly the reliability of their reports is suspect. The probabilities of failure are well-patterned by race, religion and education: higher for Blacks than for Whites; within the latter, higher for Catholics than for Non-Catholics; and inversely related to education, except among White Catholics. Although uniformly high, the proportions classified as failures are probably under-estimates of the true values for completed families, because of misreporting and continuing exposure to risk, subsequent to interview.  相似文献   

4.
Keyfitz N 《Demography》1969,6(3):261-269
Some populations, like that of the United States in the 1950's, have a smaller proportion of women of reproductive age than they would ultimately attain with continuance of their age-specific birth and deaths rates, a continuance which produces the condition known in demography as stability. Others, like that of the United States in the 1930's, have relatively more women of reproductive age than they would ultimately attain with stability. A way of studying ages is to calculate how many women of stable age distribution would be equivalent from the viewpoint of reproduction to the women observed. This stable equivalent was 69,535,000 or 16 percent below the observed United States female population in 1955, and 12 percent above the observed in 1935. The stable equivalent is a measure of fertility potential, closely related to R. A. Fisher's reproductive value. Calculations for four countries illustrate how a fall of the birth rate, for example in demographic transition, occasions an age distribution in which the stable equivalent is greater than the observed number of women. The notion of stable equivalent is useful for comparison because changes in it are nearly invariant with respect to the age-pattern of fertility used. The statement that the United States stable equivalent increased by 11 percent between 1960 and 1965 holds irrespective of whether the 1960 or the 1965 age-specific fertility and mortality rates are used as standard.  相似文献   

5.
Most young people in the United States express the desire to marry. Norms at all socioeconomic levels posit marriage as the optimal context for childbearing. At the same time, nonmarital fertility accounts for approximately 40 % of U.S. births, experienced disproportionately by women with educational attainment less than a bachelor’s degree. Research has shown that women’s intentions for the number and timing of children and couples’ intent to marry are strong predictors of realized fertility and marriage. The present study investigates whether U.S. young women’s preferences about nonmarital fertility, as stated before childbearing begins, predict their likelihood of having a nonmarital first birth. I track marriage and fertility histories through ages 24–30 of women asked at ages 11–16 whether they would consider unmarried childbearing. One-quarter of women who responded “no” in fact had a nonmarital birth by age 24–30. The ability of women and their partners to access material resources in adulthood were, as expected, the strongest predictors of the likelihood of nonmarital childbearing. Nonetheless, I find that women who said they would not consider nonmarital childbearing had substantially higher hazards of fertility postponement and especially of marital fertility, even after controlling for race/ethnicity, mother’s educational attainment, family of origin intactness, self-efficacy and planning ability, perceived future prospects, and markers of own educational attainment and work experience into early adulthood.  相似文献   

6.
Summary In 1970, Polish women in agricultural households reported larger numbers of children born alive than women in other occupations. When controlling for the influence of age at marriage and duration of marriage, the average number of children born per women among the farming population increased directly with the amount of privately owned agricultural land. Consistently, women whose principal source of livelihood was derived from non-agricultural sources even though they resided in villages, showed lower fertility than those in the agricultural sector, but significantly higher fertility than city women. This study is based on the five per cent sample of ever-married women between 15 and 70 years of age interviewed about their past reproductive histories in Poland during the 1970 Census of Population.The conclusions identify the high level of human fertility in rural populations as the main determinant of economic status among Polish peasants whose sources of support derive primarily from farming. Additional evidence supporting the hypothesis of dependence of the agricultural economy on the force of human reproduction is based on data for Slovakia and the Czech regions.  相似文献   

7.
Assisted reproductive technologies (ART) in a model of fertility choice   总被引:1,自引:1,他引:0  
We examine the relationship between assisted reproductive technologies (ART) and the microeconomics of fertility choice. Along the way, we develop a model consistent with between-country differences in overall fertility and fertility timing. Our analysis of ART centers around the distinction between biomedical and behavioral effects. While improvements in ART have the biomedical effect of raising fertility, they may cause some women who would otherwise have tried to have children earlier on in life to postpone childbirth to later in life when the conception success probability is lower. This behavioral effect of postponement may reduce the fertility rate.  相似文献   

8.
John Knodel 《Demography》1987,24(2):143-162
Examination of the reproductive histories of a sample of German married couples during the 18th and 19th centuries provides insights into behavioral changes involved in the shift from natural fertility to deliberate marital fertility control. A simple accounting scheme is used to assess the relative contributions of starting, spacing, and stopping to changes in family size during the initial phases of the fertility transition. The results suggest that in rural Germany, attempts to terminate childbearing prior to the end of the reproductive span were far more important in initiating the onset of fertility transition than efforts to deliberately prolong intervals between births or changes in the timing of the start of childbearing.  相似文献   

9.
This account reports on a project in progress that aims to obtain a comprehensive picture of contemporary fertility levels and trends in 27 low‐fertility countries. Cohort analysis is applied to review the fertility experience of women born from the 1930s through the 1970s. This choice of dates ensures that not only completed fertility but also the fertility patterns of women in the midst of or near the onset of their reproductive period are examined. In most of the 27 countries, completed fertility of successive cohorts has been declining. It appears plausible that the trends discerned in the analysis will continue in the foreseeable future. For these trends to be reversed, women who are about to enter or who are in the midst of their reproductive periods would have to adopt fertility patterns markedly different from those of women born in the 1960s and 1970s.  相似文献   

10.
Previous studies have documented varying fertility responses to childhood mortality and to the sex composition of the surviving offspring during the demographic transition. We contribute to this literature by applying a mixture cure model to reproductive histories of Estonian women born 1850–99. This model, unlike standard event history models, is capable of separating the effect of the covariates on the propensity of having another birth from their effect on its timing. Child fatalities, not having sons, and to a smaller extent, not having daughters, increased the propensity to have another child and decreased the interval to it. The response was stronger among later cohorts, but only with respect to parity progression. By contrast, the accelerated childbearing response diminished over time. Our findings suggest that behavioural responses in the quantum and tempo of childbearing can occur relatively independently.  相似文献   

11.
Using 30 years of longitudinal data from a nationally representative cohort of women, we study the association between breastfeeding duration and completed fertility, fertility expectations, and birth spacing. We find that women who breastfeed their first child for five months or longer are a distinct group. They have more children overall and higher odds of having three or more children rather than two, compared with women who breastfeed for shorter durations or not at all. Expected fertility is associated with initiating breastfeeding but not with how long mothers breastfeed. Thus, women who breastfeed longer do not differ significantly from other breastfeeding women in their early fertility expectations. Rather, across the life course, these women achieve and even exceed their earlier fertility expectations. Women who breastfeed for shorter durations (1–21 weeks) are more likely to fall short of their expected fertility than to achieve or exceed their expectations, and they are significantly less likely than women who breastfeed for longer durations (≥22 weeks) to exceed their expected fertility. In contrast, women who breastfeed longer are as likely to exceed as to achieve their earlier expectations, and the difference between their probability of falling short versus exceeding their fertility expectations is relatively small and at the boundary of statistical significance (p = .096). These differences in fertility are not explained by differences in personal and family resources, including family income or labor market attachment. Our findings suggest that breastfeeding duration may serve as a proxy for identifying a distinct approach to parenting. Women who breastfeed longer have reproductive patterns quite different than their socioeconomic position would predict. They both have more children and invest more time in those children.  相似文献   

12.
Wu LL 《Demography》2008,45(1):193-207
Historical trends in U.S. nonmarital fertility have been compiled almost exclusively from vital statistics on births. This paper complements this historical record by providing cohort estimates of nonmarital fertility for cohorts of U.S. women spanning approximately 50 years of cohort experience. Life table estimates using retrospective marital and fertility histories in the June 1980, 1985, 1990, and 1995 Current Population Surveys reveal nonnegligible levels of nonmarital fertility historically. For women born between 1925 and 1929, nearly 1 in 10 had at least one nonmarital birth by age 30. For women born between 1965 and 1969, more than 1 of 4 had one or more nonmarital births by age 30, with roughly 1 of5 white, 3 of 5 black, and 1 in 3 Hispanic women having at least one nonmarital birth by age 30. Life table estimates reveal a twofold increase between ages 20 and 30 in the percentage of women with at least one child outside of formal marriage for all cohorts of white and Hispanic women, and an increase of roughly two-thirds for all cohorts of black women. I also document qualitative differences in nonmarital fertility by race/ethnicity, with the percentage of nonmarital births following a divorce or marital separation for white women approximately twice that for black or Hispanic women. Finally, I introduce a new measure, the cohort nonmarital fertility ratio (CNMFR), which provides a cohort complement to the standard period nonmarital fertility ratio. Conservative estimates reveal a roughly threefold increase in the CNMFR for women born from 1925-1929 to 1950-1954 for both whites and blacks, despite substantially higher levels of nonmarital fertility among black women. Overall, these findings reveal surprisingly high levels of nonmarital fertility for women born since the 1920s and confirm that nonmarital fertility has become an increasingly substantial component of overall U.S. fertility.  相似文献   

13.
Measuring sterility from incomplete birth histories   总被引:1,自引:0,他引:1  
In this article, methods are presented for measuring the level and age pattern of sterility from incomplete birth histories, such as those that can be collected in demographic surveys of women who may not yet have reached the end of their reproductive span. The characteristics of the methods are examined in a simulation study that demonstrates that estimates based on information about fertility subsequent to a given age are more robust to variations in reproductive determinants, sample size, and sampling variation than the other measures, which include the frequently employed length of the open birth interval. In an illustrative analysis of World Fertility Survey data from sub-Saharan Africa, sterility was found to be high in Cameroon, intermediate in Lesotho and Sudan, and low in Ghana and Kenya relative to an English historical population.  相似文献   

14.
This report describes a study of the fertility experience of an Amazon Indian tribe that has shown evidence of having the highest documented fertility of any human group. The Shipibo, who live in the upper Peruvian Amazon, are experiencing rapid cultural change, including a decline in the prevalence of polygyny. This study tests the specific hypotheses that polygyny limits individual female and community fertility through the mechanism of post partum sexual abstinence and longer birth intervals. Total population counts in eight villages and reproductive histories of all females age 13+ show that mean birth interval lengths of polygynous women are four months longer than those of monogamous women. Fertility of polygynous women was lower, with 1.3 fewer term-births per reproductive span than that of monogamous women. The community general fertility rate is negatively associated with the proportion of polygynous birth intervals in the community. In this study, cultural change is strongly associated with higher fertility.  相似文献   

15.
The author argues that the effect of sex preference must be disentangled from the effect of number preference in Korea. This study tests--with hazard models--the effect of the number of previous children on the next birth according to the sex composition of previous children. Data were obtained from the 1974 Korean Fertility Survey. This paper also analyzes the timing of childbearing in recent periods in order to determine whether replacement-level fertility is temporary or permanent. The ideal number of children declined from 3.9 children in 1965 to 2.1 in 1991. The age-specific fertility rates for ages 20-24 years declined rapidly during the late 1980s. The fertility rates among women aged 25-29 years and 30-34 years increased during 1985-90. The proportion of fertility among women aged 20-29 years increased from 67.9% in 1975 to 86.6% in 1984. Women born in the late baby boom period of the late 1950s to mid-1960s reached prime reproductive age during the late 1980s and 1990s, but the crude birth rate remained about the same during 1985-92. A higher percentage of women (22.4%) born during 1955-59 remained single in 1990. During 1960-90, the percentage of women aged 20-24 years who were married declined. These trends indicate later age at childbearing and an explanation for the temporary nature of below-replacement fertility in the late 1980s. Korean women did not want to have more than 2 children, and the interval between first and second births increased since 1985. Among pregnancies of parity 2 conceived since 1985, over 90% of women with at least one son ended subsequent pregnancies by abortion compared to only 59% without sons. Hazard models of 1974 data reveal that son preference had an important effect on fertility. Fertility was higher among women with only daughters. Findings suggest that the value of sons must be measured at the societal and not at the individual level.  相似文献   

16.
Abstract Data from a national rural and urban sample survey are analysed in order to examine various demographic aspects of fertility in Thailand. Marital fertility rates found for Thailand are among the highest in Asia. Particularly noteworthy is the persistence of high fertility at older ages of childbearing for rural women. Cumulative fertility shows a pronounced relationship with age at marriage and current marital status. Women who marry at an older age or who experience disruption of their marriages are clearly more likely to have fewer children ever born. Differences in both current and cumulative fertility are strongly associated with residence. Rural women who constitute the vast majority of Thai women, experience the highest fertility, Bangkok-Thonburi women experience the lowest fertility and provincial urban women are characterized by an intermediate fertility level which is closer, however, to the experience of their counterparts in the capital than in the countryside. Rural-urban fertility differences are mitigated but by no means eliminated by differences in infant mortality. In both rural and urban areas a positive association between cumulative fertility and infant morality is evident. Breast-feeding, commonly practised for extended periods-among both rural and urban Thai women, undoubtedly serves to some extent as an intervening variable in this relationship. A comparison of current fertility with cumulative fertility strongly suggests that a decline in marital fertility has been under way recently among urban women, especially those residing in the capital, but not at all among rural women. Although it seems safe to assume that the urban fertility decline results in large part from an increasing use of contraception among urban women, those still in the reproductive ages who were using or had previously used birth control were characterized by higher cumulative fertility than women who had never practised contraception. Evidently couples resort to family planning only late in the family building process after they have already achieved or exceeded the number of children they wish to have.  相似文献   

17.
We use a set of linked reproductive histories taken from Sweden, the Netherlands, and Spain for the period 1871–1960 to address key issues regarding how reproductive change was linked specifically to mortality and survivorship and more generally to individual agency. Using event-history analysis, this study investigates how the propensity to have additional children was influenced by the number of surviving offspring when reproductive decisions were made. The results suggest that couples were continuously regulating their fertility to achieve reproductive goals. Families experiencing child fatalities show significant increases in the hazard of additional births. In addition, the sex composition of the surviving sibset also appears to have influenced reproductive decisions in a significant but changing way. The findings offer strong proof of active decision-making during the demographic transition and provide an important contribution to the literature on the role of mortality for reproductive change.  相似文献   

18.
In a previous paper a formula was derived from which the total fertility rate of a group of women could be estimated from the average number of live births to women in the reproductive period. In the present paper the argument is carried further and a method is given by which the total fertility rate may be estimated from the average number of children born to fertile women during the reproductive period. The method given in this paper may, under certain circumstances, have considerable advantages over the previous method suggested.  相似文献   

19.
We use a method of standardization and decomposition developed by Das Gupta to update Smith and Cutright’s analysis of demographic factors responsible for increases in the nonmarital fertility ratio (illegitimacy ratio) among blacks and whites in the United States. We create standardized rates for each year between 1960 and 1992, and consistent, exhaustive decompositions of the nonmarital fertility ratio for any interval during this period in terms of four components: (1) the age distribution of women of reproductive age, (2) the proportion of women unmarried at each age, (3) the age-specific birth rates of married women, and (4) the age-specific birth rates of unmarried women. Nonmarital fertility ratios are much higher among blacks than among whites, but both increased monotonically from 1960 to 1992. During the last 10 years, each increased by nearly 10 percentage points. Increases in the proportion of women not married, at all ages, account for the preponderance of the increase in black nonmarital fertility ratios. Increasing rates of unmarried childbearing, however, have played a role during the most recent decade (1983–1992). For whites, from 1960 until 1975, declines in marital fertility were most important in producing increases in the proportion of children born out of wedlock. Since then, these proportions have increased primarily because of increases in unmarried women s birth rates, and secondarily because of declines in the proportion of women who are married. These trends are consistent with arguments that emphasize declining economic incentives to marry and reduced access to, and acceptability of, abortion.  相似文献   

20.
This paper explores the hypothesis that the fertility transition in France entailed a structural change in behaviour from natural to controlled fertility. We define the hypothesis in terms of an empirically estimable model of lifetime fertility. The model produces separate estimates of the three main proximate determinants: the hazard rate of conception for ovulating women, the timing of ovulation resumption after a birth, and permanent sterility. Fertility control is defined as responsiveness of the conception hazard to number of surviving children. We demonstrate key features of the model by simulated family histories. The historical application provides support for the transition hypothesis in the south of France, and mixed results for the north. We also find strong evidence of persistent couple-specific heterogeneity even after controlling for unobserved heterogeneity in fecundability. We suggest how future research might improve the model.  相似文献   

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