Showing papers on "Fertility published in 1984"

The demographic transition.

Abstract: Demographic transition is a set of changes in reproductive behaviour that are experienced as a society is transformed from a traditional pre-industrial state to a highly developed, modernized structure. The transformation is the substitution of slow growth achieved with low fertility and mortality for slow growth maintained with relatively high fertility and mortality rates. Contrary to early descriptions of the transition, fertility in pre-modem societies was well below the maximum that might be attained. However, it was kept at moderate levels by customs (such as late marriage or prolonged breast-feeding) not related to the number of children already born. Fertility has been reduced during the demographic transition by the adoption of contraception as a deliberate means of avoiding additional births. An extensive study of the transition in Europe shows the absence of a simple link of fertility with education, proportion urban, infant mortality and other aspects of development. It also suggests the importance of such cultural factors as common customs associated with a common language, and the strength of religious traditions. Sufficient modernization nevertheless seems always to bring the transition to low fertility and mortality.

The proximate determinants of fertility in sub-Saharan Africa

Abstract: Rapid population growth has played an important role in producing the poor economic conditions that exist today in sub - Saharan Africa. However, in the past, few governments have expressed concern about demographic developments such as this. This is now changing and effective policies are being sought to reduce excessive fertility in order to effect a decline in the rate of population growth. The policy design and implementation of such policies would benefit from an understanding of the socioeconomic, cultural, biological and environmental factors that determine fertility. This paper seeks to provide such an understanding by assessing the proximate determinants of fertility. It is concluded that a rapid decline in fertility is unlikely to occur in the near future, partly because desired family size is very high and partly because upward pressure on fertility levels will result from the erosion of traditional childspacing practices of postpartum abstinence and prolonged breastfeeding, or from decline in levels of pathological sterility in response to public health measures.

Rapid population change in China, 1952-1982

Abstract: The remarkable changes in fertility, nuptiality, and mortality that have occurred in the People's Republic of China from the early 1950s to 1982 are summarized in this report. Data are based largely on the single-year age distributions tabulated in the 1953, 1964, and 1982 censuses of China and a major 1982 fertility survey.

Profiles of fertility, labour supply and wages of married women: a complete life-cycle model.

Abstract: Of all the major economic and demographic events in the postwar United States period, the trends in fertility and female labour supply stand out as among the most dramatic. Fertility rates, after their Depression lows, rose unexpectedly after World War II far more than was anticipated as an adjustment to the War, and continued to rise until the late 1950's and early 1960's, when they again took an unexpected turn downward all the way to today's historical lows. Female labour-force-participation rates, continuing their historical climb, grew throughout the postwar period at an increasing pace, by 4 percentage points during the 1950's, by 5 percentage points during the 1960's, and by 8 percentage points during the 1970's. These two trends are of course closely related, for most married women have traditionally spent at least some minimal time out of the labour force while caring for their own children. Thus, for example, the slower growth rate of labour-force-participation rates in the 1950's is probably connected with the higher fertility rates in that period. In this paper a complete model of female labour supply and fertility choice is constructed and estimated. The model is more complete than previous models in several respects. First, labour supply and fertility decisions are modelled as completely joint in the same sense as the consumption of two goods is joint. Second, both are modelled as life-cycle decisions, that is, as decisions regarding sequences of labour-supply and fertility events rather than levels of the same. Hence the timing of both is important. Third, the life-cycle path of wage rates is made endogenous to the model-given a wage function showing the effect of work experience on future wages, the path of wages is determined automatically by the chosen path of labour supply, which in turn is related to fertility decisions that require some period of non-work. Econometrically, the three profiles for labour supply, fertility, and wages are estimated with a full-information maximum likelihood technique that solves several econometric problems, such as the problem of heterogeneity of tastes; the selectivity problem of missing wage rates for non-workers; and the problem of simultaneous-equations bias. The value of constructing a complete model is best seen by briefly reviewing past work in this area. The modern literature in the area is based upon the work of Becker

Understanding U.S. fertility: findings from the National Survey of Family Growth Cycle III.

Abstract: The 1st overview of findings from Cycle III of the National Survey of Family Growth the latest of 7 such surveys of US fertility since 1955 and the 1st to cover all women of childbearing age in the conterminous US is presented. Interviews between August 1982 and February 1983 with 7969 women representative of 54 million women aged 15-44 reveal that sterilization is now the leading contraceptive method in the US used by 33% of all contraceptors in 1982 (22% female sterilization; 11% male sterilization) followed by the pill (29%) condom (12%) diaphragm (8%) and IUD (7%). Linked to this is the continuing decline in unwanted births since the baby boom peak in 1957 which accounted for nearly 1/2 of the drop between 1973 and 1982 in ever-married womens children ever born from 2.2 to 1.9/woman. However births conceived sooner than planned increased slightly among younger married women probably due to the large drop in pill use since 1973 and increased use of the less effective diaphragm and condom among couples still intending to have more children. Black women are now more likely than white women to use the most effective female methods: female sterilization pill and IUD. Only 45% of women aged 15-44 in 1982 had used a contraceptive method at 1st intercourse. 4 out of 5 women married for the 1st time between 1975 and 1982 had intercourse before marriage. However premarital sexual activity may be leveling off among white teenagers after a steep rise since the early 1970s and declining moderately among black teenagers. 16% of 1st marriages among ever-married women aged 15-44 in 1982 had been dissoved within 5 years mostly by divorce or separation. 59% of black women with children in 1982 had their 1st birth before marriage compared to 11% of white mothers. The proportion of babies who were breastfed more than doubled between 1970-71 and 1980-81 from 24 to 53%. (authors modified)

A Prospective Study of the Relationship Between Semen Quality and Fertility in Cases of Unexplained Infertility

Abstract: The male partners of 68 couples exhibiting 5.1 +/- 0.3 (SEM) years of unexplained infertility were assessed using the conventional criteria of semen quality, the movement characteristics of the spermatozoa and the outcome of the zona-free hamster egg penetration test. After a follow-up period of 2.3 +/- 0.06 (SEM) years, 25 (37%) of these patients were found to have initiated a pregnancy, thereby permitting an analysis of those aspects of semen quality which most accurately predicted their subsequent fertility. A multivariate discriminant analysis revealed that the conventional semen profile, per se, was not of significant value in discriminating the incidence of pregnancy. However, significant discrimination (P = 0.0173) was obtained when the postcapacitation movement characteristics of the spermatozoa were incorporated into the analysis. The accuracy of this prognosis was further increased if either the duration of infertility or the outcome of the zona-free hamster egg penetration test was taken into consideration. Overall classifications of fertility were then 76.3% and 76.5% accurate, respectively. These results suggest that in vitro assessments of human sperm function are of significant value in evaluating male fertility.

Determinants of fecundity and reproductive success in captive vervet monkeys.

Abstract: Between 1975 and 1983, adult female vervet monkeys (Cercopithecus aethiops sabaeus) over 3.5 years of age, living in two undisturbed social groups in a captive colony in Sepulveda, California, have averaged 1.0 births per female year with a mean interbirth interval of 10.7 months. Increased fecundity did not result in decreased survival rates of offspring in this population. Fecundity was influenced by the mother's age and dominance rank. The primary factor in the age-fecundity relationship was the age at first birth, which varied from three to five years. High-ranking females contributed the most to the high rate of fecundity, with significantly shorter interbirth intervals, more births per female year, and more surviving infants compared to low-ranking females.

Age at menarche and subsequent reproductive events

Abstract: A woman's age at menarche may be related to later reproductive performance, including age at first birth and risk of spontaneous abortion. This paper presents data from 2062 women with 4477 pregnancies in the Menstrual and Reproductive Health Study, a prospective study which has been in progress since 1935. Age at menarche is directly related to the age at which a woman marries and conceive a first child, but is unrelated to total fertility, frequency of induced abortion, or risk of stillbirth. Women with either early or late menarche are significantly more likely to have had an ectopic pregnancy. Overall spontaneous abortion risk declines slightly with increasing age at menarche. This trend is not seen, however, when first pregnancies alone are considered. This suggests that the overall trend with age at menarche is not related to a woman's underlying spontaneous abortion risk but rather to unknown selective factors. Women who were very young (less than 11 years) at menarche differ from the others with regard to many measures of reproductive performance. However, these women represent only a small proportion of the total study group.

Rather never than late: celibacy and age at marriage in English cohort fertility, 1541-1871.

Abstract: Most explanations of fertility change in preindustrial England emphasize changes in age at marriage. This paper shows that even after correcting for possible exaggerations in estimated celibacy rates it was celibacy and not age at marriage that accounted for most of the fertility variations before 1750. New research and new models of marriage behavior are needed. It may be necessary to abandon homeostasis to arrive at an adequate explanation of English fertility history. (authors)

Women's Status and Fertility in Developing Countries: Son Preference and Economic Security

Abstract: The relationship between women's status, which is defined in terms of the degree to which they are economically dependent on men, and fertility in developing countries is examined. The paper adopts a particular theoretical perspective regarding fertility determinants and explores the implications of women's status within that context. This perspectives gives special attention to the value of children as security assets in settings where public welfare assistance is minimal or non-existent and financial and insurance markets are poorly developed. In this context, women's economic status, and the institutional factors that create a degree of dependence, determine the relevance of sex of children in defining security goals. High dependence results is defining security goals in terms of surviving sons. Given similar security needs, and other things being equal, fertility will be considerably higher in settings where there is a strong preference for sons than in settings where son preference is weak. A cross-national empirical analysis is presented that supports this argument.

Fertility transition in Thailand: a qualitative analysis.

Abstract: This paper analyzes qualitative information gathered through focus group sessions with men and women who built their families before the Thai fertility decline and with a younger generation whose members are limiting family size to 2 or 3 children. The ultimate aim of the study is to generate qualitative data (perceptions opinions and attitudes) that will complement the quantitative documentation of the ongoing fertility transition in Thailand including its timing and pace. 4 major components are identified all of which interacted to result in an abrupt and rapid shift in reproductive patterns. 1) Fundamental social and economic changes under way in Thailand for some time are responsible in part for the latent demand for fertility control among the older generation and far more so for the current desire for smaller families among the younger. Participants viewed larger numbers of children as a burden with which they are either unable or unwilling to cope. The analysis points to a perceived increase of monetary costs of raising children and a decrease in some benefits. However some participants felt that more was to be gained from rearing few better educated children than from having many less educated ones. 2 The cultural setting is relatively conducive to the acceptance of deliberately regulated fertility and limitation of family size as adaptations to changing circumstances. There exists a prevailing expectation that each conjegal unit will be largely responsible for the support of their ownn children. In addition Thai women enjoy a considerable degree of autonomy and influence over birth control and family size enabling them to effectively take into account their own stake as the bearers and rearers of children. Finally Budddhism as practiced in Thailand also appears to pose no barriers to fertility control. 3) Organized efforts to provide contraception throughout the country met with immediate success largely because of the existence of a receptivity of latent demand for effective and acceptable birth control prior to the widespread availability of contraceptives. 4 The national family planning programs efforts to promote and provide effective modern contraception have facilitated the widespread use of birth control. The analysis shows that the 2 most dynamic components explaining Thailands fertility transition are the set of fundamental social changes that have been taking place and the effect of the family planning program. It is the interaction between these 2 forces both operating within a cultural setting conducive to reporoductive change that has resulted in the rapid and extensive decline of fertility. (summaries in ENG FRE SPA)

Pregnancy and systemic sclerosis.

Abstract: Pregnancy has been reported infrequently in patients with systemic sclerosis. Consequently, the outcome and appropriate management of such patients is uncertain. We review the obstetric experience of 19 female patients with systemic sclerosis, and report 2 women in whom 3 pregnancies occurred during the course of disease. Maternal complications included hypertension during 2 of these pregnancies and congestive heart failure during 1. There were 2 premature deliveries, although all 3 infants survived. Our experience with these patients and a review of the available literature suggest that, in patients with systemic sclerosis, fertility may be reduced and complications of pregnancy may be more frequent.

Natural fertility in pre-industrial England, 1600–1799

Abstract: Summary In this paper the result of 14 family reconstitution studies of parishes in England in the seventeenth and eighteenth centuries are analysed. It is shown that the prevailing regime of childbearing within marriage was one of natural fertility and that no convincing evidence exists, in the aggregate, for family limitation. Moreover, none of the 14 parishes when analysed individually shows any significant sign of family limitation. In addition, it is apparent that the level of marital fertility was low in comparison with other populations with natural fertility regimes and that there was little regional variation, levels and age-patterns of fertility being similar in all 14 parishes.

A demonstration of the effect of seasonal migration on fertility

Abstract: Fertility estimates were calculated using own children data from the Mexican migrant town of Guadalupe, Michoacan. In this town, 75 percent of families have a member working in the United States, and wives are often regularly separated from their migrant husbands. Simulations by Menken (1979) and Bongaarts and Potter (1979) suggest that fertility among these women should be depressed. Our results confirmed this hypothesis, showing that the seasonal absence of migrant husbands disrupted both the level and timing of fertility. However, the effect was greater for legal than for illegal migrants, a pattern that stemmed from social factors as well as physical separation. A logistic regression analysis showed that reductions in birth probabilities are greater the longer a couple is separated, and that these reductions are in the range expected from prior simulations.

Induced fertility transition: impact of population planning and socio-economic change in the People's Republic of China.

Abstract: The relative influence of population planning programs and socioeconomic development on fertility decline in the different provinces in China is assessed using provincial fertility and socioconomic data. The differences in rates of fertility decline that existed in the 1960s became larger in the 1970s even as government efforts to curtail fertility intensified giving rise to the question whether socioeconomic factors might have played a part to some extent. To examine the theory 4 hypotheses are tested for negative correlation with high fertility: higher levels of urbanization higher total output per head higher grain output per head and higher life expectancy. Except for grain output which is not found to be associated with fertility the correlation between fertility and the others is negative and statistically significant permitting the inference that fertility at the provincial level is affected by socioeconomic factors. Urbanization higher total output per head (higher standard of living) and increeased life expectancy create some of the necessary conditions for lower rates of natural increase by reducing mortality and fertility. As financial and other benefits form part of Chinas population planning program the better-off provinces are able to defray the costs involved in getting couples to limit their family size. Thus the impact of population planning activities is greater where socioeconomic change has already taken place. An analysis of Chinas fertility transition must take into consideration the socioeconomic changes of the past and present alongside government policies and programs. Tables provide statistics on Chinas birth rates by province 1949-81; population size and growth by province 1953-82; socioeconomic variables by province 1973-1980; and rates of natural increase by province and by correlation to socioeconomic measures 1978-1980.

Some Characteristics of Children's Second Families

Abstract: The structure of second families is conditioned by characteristics of children and parents at the time or remarriage and by subsequent fertility. For U. S. children whose mothers have recently remarried this report documents the ages and number of siblings at the time of remarriage, the previous marital status of the new stepfather, the duration of single-parent experience before remarriage, and the age and education of the mother. Estimates are also made of the acquisition of a half sibling through second-family fertility. Finally, the consequences of these patterns for the parental and sibling composition of the families of all U. S. children in 1980 are examined.

Conception-waits in fertile women after stopping oral contraceptives.

Abstract: Conception waits were studied retrospectively in 1403 fertile oral contraceptive (OC) users who had stopped medication in order to conceive and in 4477 controls who stopped using other contraceptives. The proportion of pill users who conceived in the 1st month was 30% less than the others but by the 3rd month this difference had disappeared. There was no excess of long conception waits in the OC group nor any evidence for a cyclic return of fertility in them. There was a highly significant interaction between pill use and age older women having a greater degree of temporary reduction in conceptions shortly after stopping the pill. There was also an interaction involving age and duration of use. In women who had used the pill for a short time there was little age effect and in younger women there was little effect of the duration of use. Older women who had used the pill for several years however had a marked temporary reduction in fertility on its cessation. (authors modified)

Fertility and Pension Programs in LDCs: A Model of Mutual Reinforcement

Abstract: Surveys of the determinants of fertility decline often include adoption of state-sponsored pension programs among the many socioeconomic changes responsible for smaller average family size. Old age insurance appears in analyses of the Western demographic experience.' Pension programs have also been suggested as a policy tool that Third World governments might use to reduce fertility.2 The theoretical literature on the pension/fertility relationship has thus far emphasized the substitution of old age benefits provided by the state for help received from children and the implications of this substitution for the value of children and desired family size. Quantitative analysis of the pension/fertility relationship has likewise proceeded in terms of the presumed impact of old age insurance.3 Very little attention has been given to the possibility that pension programs might be implemented in response to fertility decline and to consequent shifts in the demand for old age security and in the ability of the government to finance such programs. It is even possible that the pension response to falling levels of fertility could be mistaken for the assumed fertility effect of old age security programs. Our purpose is to consider and analyze both directions of effect. The literature addressing the determinants of pension expenditure has not yet been linked with the literature addressing the determinants of fertility. Doing so will not only increase our understanding of fertility patterns, but will make an important contribution to the study of how demographic demand factors influence social welfare policy. For example, Aaron and Wilensky have utilized the percentage of the population over 65 in their models of pension expenditure.4 Although