Showing papers on "Fertility published in 1978"

A framework for analyzing the proximate determinants of fertility

Abstract: Studies of the causes of fertility levels and their changes often seek to measure directly the impact of socioeconomic factors on fertility. Such procedures have a broad appeal to policymakers, offering as they do to pinpoint mechanisms susceptible to manipulation by official policy. Despite this appeal, such approaches are considerably more problematical in their application. Not infrequently, relationships are found to differ not only in magnitude but even in direction in different settings and at different times. Substantial insights can be gained if, in addition to the socioeconomic factors influencing fertility, the specific mechanisms through which these factors operate are identified. For example, the level of education of women is a socioeconomic indicator that is frequently found to be negatively related to fertility. A more detailed analysis may show that among educated women marriage is relatively late or the use of contraception more frequent, thus clarifying the relationship between education and fertility. In general, the biological and behavioral factors through which socioeconomic, cultural, and environmental variables affect fertility are called intermediate fertility variables. The primary characteristic of an intelmediate fertility variable is its direct influence on fertility. If an intermediate fertility variable, such as the prevalence of contraception, changes, then fertility necessarily changes also (assuming the other intermediate fertility variables remain constant), while this is not necessarily the case for an indirect determinant such as income or education. Consequently, fertility

Human Fertility: the basic components

Abstract: In this innovative and comprehensive work, expanded by one-third for the English-language edition, Henri Leridon integrates biology and demography to investigate human fertility, both natural and controlled. Traditionally, demographers have been concerned with birthrates in different populations under varying conditions, while biologists have limited themselves to the study of the reproductive process. Leridon has formulated the first coherent overview of the functioning of the human reproductive system in relation to the external conditions that affect fertility. The book begins with a readable, authoritative review of human fertility in its natural state. Leridon summarizes and evaluates current knowledge, drawing together rare statistical data on physiological variables as well as demographic treatments of these data. After discussing the classical framework used by demographers, Leridon undertakes a "microdemographic" analysis in which he focuses on the individual and explicates the biological processes through which social, psychological, and economic factors affect fertility. He isolates its components fecundability, intrauterine mortality, the physiological nonsusceptible period, and sterility then reviews the composite effect of variation in any one component. Leridon considers situations of controlled fertility: contraception, abortion, and sterilization. The author also presents valuable new data from his own investigations of varying risks of intrauterine mortality. Finally, he shows how the previous approaches can be complemented by the use of mathematical models."

Population, Food Intake, and Fertility

Abstract: Historical data provide support for the hypothesis that poor nutrition strenuous physical labor and substandard living conditions may account for the relatively small completed family size of the lower socioeconomic classes in Britain in 1850-60. The relatively late age at menarche (15.5-16.5 years) and late attainment of adult height suggests that some submaximal fecundity in combination with a late age at marriage may have also contributed to the small completed fertility of the upper classes. Married couples of this historical period produced only 6-7 children during a time when contraceptive devices were expensive and ineffective. Nutrition hard work and disease can affect fertility because reproduction requires energy and is synchronized with physical development. The undernourished female has later menarche and earlier menopause and a higher frequency of anovulatory menstrual cycles. In the adult male severe undernutrition results in loss of libido a decrease in sperm count a decrease in prostate fluid a loss of sperm mobility and even the cessation of sperm production. Historical reports indicate that about 25% of female mill workers suffered from retarded or suppressed menses and absolute sterility occurred in about 15% of marriages. Children who worked in factories had extremely slow physical growth and hence later sexual maturation. Undernutrition not the widespread use of traditional methods of contraception may also be the explanation of the completed family size of 6-7 children found in many developing countries today.

Conditions of fertility decline in developing countries 1965-75.

Abstract: This paper is a macro-analysis of the correlates of fertility decline in developing countries for the period 1965–75, during which there was substantial fertility decline in Asia, quite a bit in the Americas, some in North Africa, and almost none in black Africa. The analysis focuses on how much of the fertility decline is associated with such socioeconomic variables as health, education, economic status, and urbanization, or with “modernization” as a whole, and how much with popula­tion policies and programs, primarily family planning programs, designed to reduce rates of growth.

Adult Height and Fertility in Men with Congenital Virilizing Adrenal Hyperplasia

Abstract: The effects of congenital adrenal hyperplasia on adult height and fertility were studied in 30 afflicted men. The patients' heights ranged from 150.0 to 178.6 cm (mean ±1 S.D. of 164.0±7.6), which is significantly lower than both the mean adult height for American men and that of the patients' parents (P<0.005). There was no correlation between adult height and the age at which therapy was begun, possibly because the patients treated before one year of age had the salt-losing form of the syndrome. Therapeutic compliance may also have been involved. Apparently normal fertility, indicated by paternity and normal sperm counts, was found in 18 out of 20 patients evaluated. This group included five untreated patients who were found to be fertile and to have normal plasma testosterone and gonadotropin but elevated androstenedione levels. (N Engl J Med 299:1392–1396, 1978)

The Decline of Belgian Fertility, 1800-1970

Abstract: Fertility in Belgium declined early and remained low compared with that in other European countries. For this reason, and because of the nation's heterogeneity, study of its demographic transition illuminates the relationship between fertility behavior and socioeconomic development. Professor Lesthaeghe first describes the Belgian experience in a way that permits direct comparison with that of other European nations. He then tests the several explanatory hypotheses for the European fertility decline against his data. Belgium's heterogeneity in the nineteenth-century and in the first half of the twentieth was economic, social, and cultural. Some areas of the country underwent industrialization as early as 1800-1830, while others shifted away from agriculture and artisanal modes of production only between 1880 and 1910. Between 1890 and 1900, regional fertility levels differed drastically, as did regional infant mortality rates and life expectancies at birth. In addition, wide variation occurred in the process of secularization, linguistic characteristics, demographic trends, and other cultural indicators. By describing and analyzing these data in relation to Belgium's fertility decline, Professor Lesthaeghe makes a major contribution to the theory of the demographic transition that occurred throughout Europe. Originally published in 1978. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

Nonrecursive models of labor force participation, fertility behavior and sex role attitudes.

Abstract: A negative relationship has been established between female labor force participation and fertility but there has been considerable controversy over the direction and causes of this relationship. 2 causal models of the actual fertility and work behavior of a national sample of married women aged 30 in 1970 are examined using the 2-stage least-squares technique to disentangle reciprocal effects. A 2-variable feedback loop incorporating only fertility and labor force participation and a 3-variable model which adds sex role attitudes to the endogenous variables are included. Much of the work-fertility relationship can be accounted for by controlling background variables such as education and marital duration yet a negative effect from fertility to labor force participation remains. Adding sex role attitudes to the model as a potential source and consequence of fertility and work behavior slightly reduces the size of this effect. In sum the results seem to indicate that the worker and mother roles were to some extent incompatible for these young married women. For this cohort at least the childbearing and rearing role appears to have taken precedence. Work behavior was influenced by the number of children the women had during their 20s; childbearing was not influenced by their work.(AUTHORS MODIFIED)

Fertility after stopping different methods of contraception.

Abstract: Data on the return of fertility after discontinuing various methods of contraception were collected from among the women taking part in the Oxford-Family Planning Association contraceptive study. Return of fertility was measured as the time taken to give birth to a child. The fertility of both nulligravid and parous women who stopped taking oral contraceptives was initially impaired in comparison with that of women who stopped using other methods of contraception. But the effect of oral contraceptives on fertility had become negligible by 42 months after cessation of contraception in nulligravidae and by 30 months in multiparae. Impairment seemed to be independent of the length of use of oral contraceptives. Data relating to IUD users were sparse, but the figures that were available were reassuring. These results suggest that, although women may have temporary impairment of fertility after discontinuing oral contraception, they are unlikely to become permanently sterile through taking the pill.

Age and marital status at first birth and the pace of subsequent fertility.

Abstract: Taking care to minimize the truncation bias inherent in cross-sectional data and controlling for other variables, this paper demonstrates the strong effects of both age and marital status at first birth on the pace of subsequent fertility. These effects are particularly strong in the interval immediately following the first birth but persist even into the fourth interval. Important differences are found with respect to the experience of rapid fertility, rather than in the mean lengths of intervals. These results add to the growing attention to the social dimensions of age as a variable in fertility processes.

Early childbearing and subsequent fertility.

Abstract: Data from the National Survey of Family Growth which was conducted by the U.S. National Center for Health Statistics in 1973-1974 were searched for the relationship between early childbearing and subsequent fertility. The data show that early age at 1st birth especially if the mother is a teenager correlates with more rapid and higher levels of subsequent fertility. Women who start their childbearing in their teen years tend to have more unwanted and out-of-wedlock births. This is true within racial educational and religious subgroups. Marital status at 1st birth had little effect on subsequent fertility. Previously observed fertility differences between blacks and whites are largely attributable to differences in age at 1st birth. Blacks in fact seem to have slowed the pace of their current childbearing perhaps due to the growth of federally subsidized family planning programs in recent years. There are still differences in subsequent fertility between Catholics and non-Catholics when age at 1st birth is controlled. Subsequent childbearing seems to have no relation to whether the 1st birth was considered wanted or unwanted. Education proves to be an important predictor of contraceptive use and success. The reasons for this are complex.

The household life cycle and economic mobility in rural Bangladesh.

Abstract: In rural Bangladesh domestic organization is patriarchal ownership of land is concentrated among men and inheritance customs and laws favor sons. Sons establish their new households soon after marriage usually about 28 and they then assume independent authority while usually being given right to a portion of their fathers land. A household cycle ends at the death of the patriach in each household. Household expansion is achieved through reproduction; the average number of surviving children is 5.5 per family. Several features link the demographic evolution of the household to its economic fortunes: 1) the household depends on labor supplied by its members and sons particularly provide parents with economic returns 2) in time of crisis (illness of the patriach flood) a household with mature sons faces a smaller risk of economic decline and 3) following the patriach deaths the risk of property loss is diminished by the presence in the household of mature sons and other dependents capable of claiming the inheritance. These reasons explain why in rural Bangladesh the household strategy of risk aversion is best served by maximizing fertility which is likely to produce greater number of male births and consequently of surviving sons. Also since wives face a high probability of widowhood it is in their interest to produce sons that can provide for them in their later years. Not surprisingly class differentials depend heavily on child and infant mortalitya s much as on adult mortality. As fewer children of the poor survive to maturity and those who survive leave their parents household at an early age the poor face a higher risk of property loss and economic decline. The article suggests that projects for rapid fertility decline in Bangladesh are not promising.

Factors influencing the fertility of a cattle population.

Abstract: The many factors which may influence the fertility of a cattle population are reviewed. The following subjects are discussed: the bull, the method of insemination, the cow, the conditions of herd management and chance. Particular attention is paid to factors related to the conditions of herd management. These are the climate, the season, the size of the herd, the housing system, the choice of a bull, hygiene at the time of calving, the interval between parturition and the first insemination, detection of oestrus, the time of insemination during oestrus, nutrition, selection and the culling of cows. In the discussion, the effect which the various factors may have on fertility is illustrated by a case in point.

Determinants of fertility in advanced societies

Abstract: This book is an overall review of the research and theories on the social factors determining fertility in advanced countries. The question is both how to beget enough children and not too many. Measures of fertility are standard: age-specific birth rate crude birth rate. The theories of fertility are Malthuss theory of population; demographic transition; and economic theory. Determinants of fertility in centuries preceding the modern period are based on parish registers genealogies and literary sources. The economic and social background of the decline of fertility in some parts of Europe and high fertility in others is reviewed. The sources of data are Time series of vital statistical data census fertility data fertility surveys and international regional cross-sectional analylses of fertility. The social factors of fertility are marriage and knowledge of birth control. Demographic profiles are a social measure of determinant factors. An attempt is made to combine the economic and sociological theories of fertility. Womens status is one of the primary determinants the author concludes. Womens education and employment history determines whether or not she stays at home. Whether or not a woman stays at home determines her reproductive history. Nurseries and daycare centers may affect a womans decision about producing children.

Marital Homogamy the Second Time Around.

Abstract: Recent declines in the marriage rate and increases in the prevalence of remarriage point to the need for more careful analysis of the nature of second marriage. Very few sound empirical data are available concerning the mate selection or adjustment processes of second marriages, and this hampers the development of useful, generalized knowledge about remarriage. Utilizing data from the 1970 National Fertility Survey, this paper compares the levels of marital homogamy-in age, education and religious identification-of women in their first marriages and women in their second marriages, as well as in the previous marriages of the twice-wed women. The analysis shows that twice-wed women experience low homogamy in both their current and first marriages. The persistence of this pattern through the application of controls for status, age, and religiosity indicates that the differences do not result primarily from marriage market constraints. Though several caveats are noted, the results support the perspective that some women, either because of their conception of marriage, or because of their mate selection pattern, are disproportionately prone to divorce and remarry. The implications of these findings for divorce trends are discussed.

Natural fertility in pre-industrial Germany

Abstract: Summary Evidence from the analysis of reconstituted family histories of couples married before 1850 based on ten village genealogies suggests that family limitation was largely absent in pre-industrial German village populations. By and large, marital fertility schedules of this pre-industrial period conform to the age pattern of natural fertility. Women bore their last child at relatively high ages and apparently were not influenced by previous experience with infant and child mortality. These findings seem to hold over a substantial period and across villages in very different areas of Germany. A positive association between age at marriage and marital fertility at a given age was evident, but in most cases all or a substantial proportion of this relationship could be attributed to several plausible mechanisms other than deliberate attempts to limit family size. In addition, the age at last birth appeared to be unrelated to age at marriage. The results cast doubt on assertions that birth control was wid...

Declining world fertility: trends, causes, implications.

Abstract: This Bulletin examines the evidence that the worlds fertility has declined in recent years the factors that appear to have accounted for the decline and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world the authors derive estimates which indicate that the worlds total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975 thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors projections which are compared to similar projections from the World Bank the United Nations and the U.S. Bureau of the Census indicate that by the year 2000 less than 1/5 of the worlds population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."(AUTHOR ABSTRACT)

Productivity and Reproductivity: Fertility and Professional Achievement among Research Scientists

Abstract: Data for a group of research chemists are examined to test the hypothesis that marital fertility is associated with lower levels of research productivity and to assess the extent to which the fertility-productivity relationship varies by sex. The results show a negative relationship between fertility and productivity among the scientists; the relationships for the sexes are similar in direction and magnitude. We argue that previous studies of the impact of marital fertility on career attainments have failed to find the expected negative association because they have dealt with workers who cannot freely invest extra time and energy in work efforts and because they have used inadequate measures of attainment such as occupational mobility rather than more direct measures of job performance. The idea that occupational success is negatively associated with fertility is a classical hypothesis in social demography. Ambition for social achievement, it is reasoned, motivates couples to limit the number of their children in order to free the time, energy, and money which are usually required to rear a large family, for economic and occupational pursuits (Berant; Westoff et al.). Investing these resources in occupational activities should result in superior economic or occupational performance, which should in turn be reflected by later career success. The hypothesized negative association between career success and fertility should be due in part to deliberate attempts by ambitious couples to limit their fertility and in part to the advantages which extra resources confer on couples who have fewer children, regardless of the reasons for their lower fertility. *We are grateful to Paul D. Allison and Paula M. Hudis for their comments on a previous draft of this paper.

Trends in fertility family size preferences and family planning practice: Taiwan 1961-76.

Abstract: A time-series of 6 sample surveys was undertaken in Taiwan during 1965-1976 to determine trends and differentials in reproductive behavior. The first 3 surveys show a rapid increase in contraceptive practice and a rapid decline in fertility between 1965-1970. It is speculated that the fast rate of socioeconomic development combined with establishment of an islandwide Taiwan Family Planning Program after 1964 effected this observed fertility decline. Sharp increases were observed in the proportions of women wanting no more children at younger ages lower parities and earlier marriage durations. The preferred number of children has continued to drop in all major population subgroups. While the traditional Chinese son preference continues even this has been made to coincide with this lessening preferred number of total children. The use of contraception increased during the survey years among both couples wanting and couples not wanting additional children. Contraception for spacing purposes has risen. Survey data on contraceptive practice and preferred number of children suggests that cumulative fertility will continue to decline in the future.

The unmet need for birth control in five Asian countries.

Abstract: Using data from the World Fertility Survey interview a comparison was made to examine contraceptive use and couples fertility intentions in Korea Malaysia Pakistan Nepal and Thailand. Thailand 55%). In Korea where desire for male offspring is great contraceptive practice increases greatly after the birth of 1 or 2 sons. Thus sex predetermination technology made available could alter timing of contraceptive practice and also fertility in Korea. Although education of women affects contraceptive use there is considerable variation across countries of women at the same level of education. Contraceptive methods varied. In Nepal over 75% of the women knew of no method of contraception. In Pakistan where 75% of the women knew of a method only 1/3 knew of a source of information and services.

The determinants of marital fertility in the united states, 1968-1970: inferences from a dynamic model

Abstract: Criticizing the static assumptions of previous socioeconomic and microeconomic models of marital fertility, particularly regarding the sequential and stochastic facets of family building, this paper advocates a dynamic perspective. Of particular concern is the assumption of equilibrium family size made by those who employ the static perspective. The equilibrium family size assumption implies that the parameters relating social and economic variables to fertility will be similar for all births, regardless of order. To test this assumption of constancy, a two-equation model of fertility and female employment is introduced. Contrary to the static perspective’s implication of constant effects, substantial parity differences in the estimates of parameters for both equations are reported, as are several differences between blacks and whites. On the basis of this evidence, I conclude that the static decision-making framework should be replaced by a dynamic approach to marital fertility.

Effects of Parental Consanguinity on Fertility, Mortality and Morbidity among the Pattusalis of Tirupati, South India

Abstract: The incidence of consanguineous marriages is very high in the Pattusali population. First cousin marriages are preferred mostly. The consanguinity effects obtained in this population are also mostly c

Nutrition and human reproduction

Abstract: Issues, Definitions and an Analytic Framework.- Nutrition and Endocrine Fmiction.- Introductory Statement.- The Maintenance of Infecundity in Postpartum Women.- Impact of Malnutrition on Reproductive Endocrinology.- The Effect of Oral Contraceptives on Micronutrients.- Nutrition, Fertility and Infmt Mortality.- Introductory Statement.- Nutrition, Fatness, and Fertility: The Effect of Food Intake on Reproductive Ability.- Famine and Fertility.- Effect of Maternal Nutrition on Infant Mortality.- Nutrition, Breast-Feeding, and Fertility.- Introductory Statement.- The Impact of Prolonged Breast-feeding on Birth Intervals and on Postpartum Amenorrhea.- Maternal Nutrition, Breast-feeding and Infant Survival.- Economic Aspects of Breast-feeding.- Analytical Models of Nutrition-Fertility Relationships.- Introductory Statement.- Reproductive Models in the Study of Nutrition-Fertility Interrelationships.- Fecundability and Contraceptive Opportunities.- Malnutrition in Central Africa.- Field Studies.- Introductory Statement.- The Influence of Nutrition on Fertility: The Case of Senegal.- Relations Between Birth Intervals and Nutrition in Three Central African Populations (Zaire).- Nutrition and Birth Interval Components: The Guatemalan Experience.- Effect of Maternal Nutrition on Fertility in Rural Bangladesh.- Variations on Fertility with Breast-feeding and Contraception in Urban Filipino Women: Implications for a Nutrition Program.- A Study of Birth Interval Dynamics in Rural Java.- Economic Determinants of Breast-feeding Behaviour: The Case of Rural Households in Laguna, Philippines.- Contributors.

Age at menarche socio-sexual behavior and fertility.

Abstract: The purpose of this study is to examine factors associated with mothers age at first birth specifically to examine the process whereby age at menarche may affect the timing of the first birth. A sample of 541 black and white women aged 15-29 at time of their first birth was drawn from the birth records of residents of Brooklyn the Bronx and Queens in New York City. Mean age at menarche was 12.7 for blacks and 12.3 for whites; the mothers education was only weakly associated with age at menarche. There seems to be a direct relationship between age at menarche and fertility only for black women. Age at menarche may be a crude indicator of fecundity but does not seem to influence the timing of the first birth. However there is some evidence that for girls who did not use contraception at the time of their first sexual experience early age at menarche may be related to early age at first birth. Age at menarche does influence the timing of dating and consequently the timing of motherhood for black women only. Age at first date is correlated with age at first sexual intercourse especially for blacks.

Some speculations on the future of marriage and fertility.

Abstract: It is projected on the basis of current factors depressing fertility that the U.S. will reach zero population growth in about 50 years and that at a population of about 250 million; it will then begin to decline. Factors cited are available and effective contraceptive technology radical changes in the institution of marriage (massive postponement of marriage and high divorce cohabitation and illegitimacy rates) which in turn are based on changes in the role of women particularly greater educational and employment opportunities. Although it is asserted that these demographic changes seem desirable because of less pressure on the environment and resources with an opportunity to improve the quality of life the question is raised whether the changes taking place in the institutions of marriage and the nuclear family are so far-reaching as to require eventual serious government subsidization of reproduction.