World Fertility Survey Research Articles

Sterility in sub-Saharan Africa

Simulations and empirical findings justified the estimation of sterility by age in many African countries where the prevalence of sterility has not been measured previously. Simulations indicated that age-specific sterility rates between ages 20 and 44 may be obtained from populations that use contraception, as long as the rates of contraceptive use and contraceptive efficacy do not exceed specified limits, and the sample size is at least 1,500 cases. In Botswana, Kenya, and Zimbabwe contraceptive practice has become so prevalent, that measures of sterility were deemed to be biased when all women were included in the samples analyzed. The prevalence of sterility varied markedly across selected African countries, and was high relative to levels prevailing in populations with little disease. Prevalence of sterility was highest in Cameroon and lowest in Burundi. In Cameroon and Sudan sterility before age 35 appeared to have declined slightly from the World Fertility Surveys around 1980 to the Demographic and Health Surveys around 1990. In Ghana, Kenya, Nigeria, and Senegal there was evidence of a decline in sterility during the 1980s.

Using Parity-progression Ratios to Estimate the Effect of Female Sterilization on Fertility

In this article, a new methodology that employs parity-progression ratios to estimate the effect of female sterilization on fertility is described, and results using data from Ecuador are compared to those obtained using a previously existing approach that classifies women by marital duration. The methods differ in how they disaggregate marital fertility and in the assumption they make about what the subsequent fertility of sterilized women would have been if they had not been sterilized. The analysis of the Ecuadoran data shows that the estimate of births averted by sterilization has diminished over time, even as sterilization prevalence has been increasing. This situation is attributed to a decline in the fertility of nonsterilized women resulting from increased use of reversible methods of contraception.

Statistical Models for Causal Analysis.

This book provides a quick overview of statistical models commonly used in causal analyses of nonexperimental data in the social and biomedical sciences. Topics covered are simple bivariate regression multiple regression multiple classification analysis path analysis logit regression multinomial logit regression and survival models (proportional hazard models and hazard models with time dependence). The methods described are illustrated using data from the 1974 Fiji Fertility Survey conducted as part of the World Fertility Survey. (EXCERPT)

The end of fertility: age, fecundity and fecundability in women

Onset of capacity for childbearing in women is dated biologically by menarche, although actual onset may be delayed. The end of childbearing is less understood but recent demographic and biological research on fertility at older ages in clarifying the end of fertility. The demographic view of declining fertility with age is based on age-specific fertility in natural fertility populations, artificial insemination and pregnancy rates by age and World Fertility Survey data. New data from the Demographic and Health Surveys on exposure to the risk of pregnancy shows that whereas older women biologically need longer exposure to pregnancy, exposure declines on behavioural grounds such as duration of marriage. Actual fecundity is obscured by factors of fecundability. Recent research on medically assisted conception is adding to the understanding of declining fecundity with age, especially the relative contributions of endometrial and ovarian ageing. This paper reviews the available information on declining fertility with age and discusses the implications of the extension of fertility through new medical technologies.

Twelve-year follow-up of respondents in a sample survey in peninsular Malaysia

"This note reports the experience of an attempt to find and re-interview in late 1988 and early 1989, as part of the Second Malaysian Family Life Survey (MFLS-2), the female respondents to the 1976-77 Malaysian Family Life Survey (MFLS-1) and a sample of their adult children aged 18 or older.... We discuss the field methods used to track the panel members and their adult children, report follow-up rates and analyze the selectivity of attrition from the panel, using data from the MFLS-1 on characteristics of both the missing and the re-interviewed respondents and their families. We then discuss the degree to which these results might be generalized to other such attempts at re-contacting survey respondents."

Seeking Common Ground: Unmet Need and Demographic Goals

Population growth has been a world issue since the 1950s. The debates of the 1960s and 1970s focused on how best to achieve fertility decline: through family planning service provision or development. The Bucharest World Population Conference of 1974 established that socioeconomic development was a necessary precondition to fertility decline. Family planning funding stagnated until evidence was provided from the World Fertility Surveys and the Demographic and Health Surveys (DHS) that there were high levels of unwanted fertility. By 1992 environmentalists had joined family planners in addressing population growth as a serious concern. Environmentalists saw growth as an impediment to environmental sustainability. An estimated 56% contraceptive prevalence level is needed in order to achieve the UN medium variant of population projection by the year 2000. Contraceptive use worldwide has increased but the numbers of women not practicing any form of contraception has declined very little. Surveys have indicated that sub-Saharan Africa was the most behind in meeting unmet demand. Studies of the relationship between stated fertility desired and actual fertility by different development levels showed that both actual and desired fertility declined with increased socioeconomic development. Regardless of level of development unwanted fertility remains constant. Meeting unmet family planning need was considered more effective in achieving replacement level fertility than by increasing contraceptive prevalence. Satisfaction of the about 17% of women with unmet need would reduce the fertility rate by 1.13 points without including China. If China were included fertility would decline to 3.11. The fertility decrease of 44% would meet the UN medium variant of desired fertility of 3.34 by the year 2000. Contraceptive prevalence could be increased from 42% to 59% by meeting unmet need in 10 years but not 7 years. Programs should emphasize health and not targets in satisfying individual and societal goals.

Breastfeeding and waiting time to conception for Malay women: a tale of two surveys.

This study investigates the unusual relationship between breastfeeding and waiting time to conception in Malaysia as reported in Goldman et al. (1987). Using data from the Malaysian World Fertility Survey (MWFS), Goldman and her colleagues (1987) find that noncontracepting Malaysian women have an unusually long waiting time to conception, given their relatively short durations of breastfeeding. This study provides a similar analysis using data from the Malaysian Family Life Survey (MFLS) and finds a more typical relationship. I conclude that the distinction between full and partial breastfeeding made to respondents of the MFLS probably led to more reliable responses to questions about breastfeeding duration, especially for women who breastfeed for long durations.

Estimates of Birth Intervals in Pakistan, with and without the WFS Restrictions

Almost all the World Fertility Surveys (WFS), and those repeating a similar pattern of pregnancy history data collection, like the Population, Labour Force, and Migration Survey (PLM) carried out in Pakistan in 1979-80, covered information on proximate determinants for the last closed and open birth intervals. This paper, based on the PLM data, discusses the methodological issue of data collection. The types of restriction used have often been doubted as they have produced biased estimates of contraceptive use and duration of breast-feeding, which are important in the estimation of birth interval and in the ultimate estimation of the structures of the relationship predicting fertility. The representativeness of the last closed and open birth intervals is limited if these are probed deeper in the time before survey, as the proportion of births gets quite small. It is inappropriate to estimate proximate determinants on fertility data that do not provide information on all the births. Therefore, an attempt has been made to estimate contraceptive use and breast-feeding with and without the WFS restrictions. The logit model has been used with a dichotomous variable, 'whether the next live birth occurs or not', on proximate determinants and other socio-economic variables to estimate the amount of biasedness. The results reveal that there appears to be a higher proportion of unbiased estimates if they are derived through the unrestricted sample; and these results are in conformity with the results found elsewhere. The biasedness of the restricted samples also affects the studies aimed at observing the relationship between the predictor and the dependent variables.

Changes in breastfeeding initiation and duration in Peru, 1977–1986

Both breastfeeding initiation and duration increased in Peru during 1977-86. Although one would have expected that the average incidence and duration of breastfeeding would have declined as a result of changes in population characteristics, the potential for an overall decline was more than overcome by changes in behavior. A net increase in initiation and duration is shown for all subgroups of interest. The largest absolute increases are documented for children who, in 1977, were the least likely to be breastfed and who were breastfed for the shortest durations.

Mean Duration of Breastfeeding Has Risen in Some Developing Countries, Fallen in Others Since 1970s

Data from 62 World Fertility Surveys (WFS) and Demographic and Health Surveys (DHS) conducted in 47 countries prior to 1990 indicate that the average duration of breast feeding ranges from 30.4 to 24.6 months in Bangladesh and Nepal respectively to 2.9 months in Costa Rica. The average duration of breast feeding was 18.3 and 17.2 months respectively in Africa and Asia and the Pacific vs. 9.5 months in Latin American and the Caribbean. The trimean duration of breast feeding in Africa ranged from 14.0 months in Morocco to 23.7 months in Burundi compared with a range of 4.1-30.4 months in Asia and the Pacific. In Africa children ever breast fed fell below 95% only in Cote dIvoire and Egypt. In Asia and the Pacific the proportion was 90% or higher in all countries except and the Pacific the proportion was 90% or higher in all countries except Fiji (86%) Malaysia (75%) the Philippines (85%) and Syria (88%). In Latin America and the Caribbean this proportion was less than 85% only in Costa Rica (74%) Mexico (81%) Panama (80%) and Trinidad and Tobago (80%). Average duration of breast feeding increased by 2 months in Ecuador Ghana Kenya Peru and Trinidad and Tobago. In contrast declines of 1-3 months were found in the Dominican Republic Indonesia Morocco Thailand and Tunisia. Women living in rural areas breast fed for 3.7 months longer in Africa 5.3 months longer in Asia and 4.6 months longer in Latin America and the Caribbean than their urban counterparts. Individual surveys showed large rural-urban differentials: 8 months in Morocco Panama Peru and Venezuela in the WFS; 12 and 9 months in Thailand WFS and DHS respectively; and 11 months in the Indonesia WFS. In Africa the current-status trimean for breast feeding duration fell from 19.7 months among those with no education to 15.9 months among those with 4-6 years of education and to 14.2 among those with 7 or more years of education. Increases in breast feeding duration either by education or by residence were found in Ecuador Ghana Kenya Mexico Peru Sri Lanka and Trinidad and Tobago. The most educated women and those living in urban areas had the highest gains.

A New Approach to Eliciting Information about Induced Abortion

Reliable quantitative data on abortion are sorely needed, particularly in developing countries. Past experience in large-scale survey research has demonstrated that direct questioning on this subject results in significant underreporting. This article presents results of an experiment to collect data on induced abortion in Côte d'Ivoire within the context of a family planning operations research study. First, questions were employed to broach the topic of unwanted pregnancy in a value-free manner, and then the potential for a variety of actions, including abortion, was acknowledged. The results indicate that approximately 25 percent of all women attending a family planning clinic on the day of the survey had had an induced abortion. The use of improved abortion-related questions shows promise for providing more complete measurement of a neglected dimension of women's reproductive health.

Contraception and women's health.

More and more women all over the world are opting for fertility by choice not by chance. Contraceptive use has a tremendous impact on women's health. The ability to regulate and control fertility is a basic component of health, positively defined as a state of physical, mental and social well-being. Contraception is saving the lives of women around the world from the hazards of unwanted pregnancy. Optimal childbearing is also contributing to infant and child survival. Contraception has a complex relationship to sexually-transmitted diseases. Contraceptive safety is a major public health concern. The risk/benefit assessment will differ for different populations, for different individuals, and even for the same individual at different periods of life. The family planning movement started as a movement by women for women. Women's perspectives and women's concerns should guide the future of contraceptive research and development.

The practice of terminal abstinence in Nigeria and Cameroon.

World Fertility Survey (WFS) data from Nigeria and Cameroon are used to examine the practice of permanent sexual abstinence in relation to menopause status to test the assumption that terminal abstinence may represent a "cultural menopause." Terminal abstinence is also examined in relation to cumulative fertility to determine if the cultural practice of abstinence at the biological end of reproductive life affects lifetime fertility. Among married, not pregnant women ages 31-49, the frequency of terminal abstinence is 4.3% in Nigeria and 4.6% in Cameroon. The frequency of terminal abstinence increases with age. Using probit analysis, the median age at menopause precedes the median age at terminal abstinence. Chi-square tests indicate significant relationships between terminal abstinence and menopausal status, although the relationships are country specific. Women in Nigeria who report terminal abstinence are more likely to be pre-menopausal, while in Cameroon terminally abstinent women are more likely to be post-menopausal. ANOVA and t-tests demonstrate no significant relationship between terminal abstinence and cumulative fertility, although there are significant relationship between terminal abstinence and number of miscarriages, religion, education (in Cameroon), and having grandchildren through sons (in Nigeria). The timing of terminal abstinence is considered in relation to various time scales: chronological age, family stage, and reproductive stage. In Nigeria the scale of family stage appears to be important in determining the timing of terminal abstinence, while in Cameroon the scale is more likely to be gynecological. © 1993 Wiley-Liss, Inc.

Population trends, issues and implications.

"The aim of the paper is to provide an overview of the population trends in Africa, the critical population issues of the region and their implications, as well as linkages with important social and economic sectors such as education, health, employment, food and nutrition etc. The time frame for the paper is the recent past and the immediate future until 2025 for which United Nations projections are available. The data utilized in the paper are the United Nations Population Projections as assessed in 1988 supplemented by information available from various surveys and studies, particularly the World Fertility Surveys and Demographic and Health Surveys."

The Influence of Rural-Urban Migration on Migrant's Fertility Behavior in Cameroon

An autoregressive model has been applied to the 1978 Cameroon World Fertility Survey data to test the fertility adaptation hypothesis of rural-urban migration. The fertility differential between rural-urban migrants and rural stayers is very small in Cameroon when compared with that of Korea and Mexico. However, the lack of fertility differentials between rural-urban migrants and rural stayers which are the result of the unique cultural and biosocial parameters of African fertility does not imply a weak fertility adaptation effect.

An Experiment Using a Month-by-Month Calendar in a Family Planning Survey in Costa Rica

Recent demographic surveys have incorporated a month-by-month calendar for the five-year reference period before the survey for the recording of fertility-related events (sexual unions, contraceptive use, pregnancies, and breastfeeding). In the 1986 survey of Maternal and Child Health and Family Planning in Costa Rica, approximately one-half of the 3,527 women interviewed were administered a questionnaire with traditional fertility and family planning questions; the other half were asked virtually the same questions, but the women's responses were entered in a month-by-month calendar. The assignment of questionnaire type was randomly alternated by cluster. Comparisons of the number of events (live births, pregnancy losses, and contraceptive use) showed that more events were recorded among the women in the calendar group. Significantly less erroneous superposition of events (contraceptive use in the last trimester of pregnancy and hormonal contraceptive use in the first month postpartum) was noted when the calendar was used.

Contributions of the proximate determinants to fertility change in Senegal.

The 1978 World Fertility Survey (WFS) and the 1986 Demographic and Health Survey (DHS) data are used to examine the relative contributions of three proximate determinants (nuptiality or marriage, contraception and post-partum infecundability) to fertility change in Senegal. The aim is to identify the important variables that is amenable for policy towards fertility reduction. Analysis shows that there are increases in the absolute measures of all three determinants. The magnitude of change is greatest in contraceptive use, moderate in marriage but least in duration of breast-feeding. However, the index of contraceptive use exerts the least impact on fertility reduction while that of post-partum infecundability makes the strongest impact on fertility. The impact of the nuptiality index on fertility change lies in-between contraception and breast-feeding.

Stalking the Elusive "Unmet Need" for Family Planning

The discourse on unmet need in family planning (FP) emphasizes the need to obtain better conceptualizations based on the experiences of southern hemisphere countries. Unmet need has become a concept important for policy decisions, program strategies, budgeting, and resource allocations. The concept varies with the survey questions, with the definitions, and through the exclusion of factors. Conventional means exclude the needs of those not in consensual or marital unions and those who report use of a contraceptive. The exclusion of these women can have a sizeable impact. Unmarried people of reproductive age range from 8% in Mali to 46% in the Dominican Republic. In a study of unmarried women in Paraguay, 6% of single women had an unmet need by their own definition. Contraceptive users may be grouped three ways: 1) those wanting to avoid or postpone a pregnancy and who are using an ineffective method; 2) those who are using a theoretically effective method incorrectly or sporadically; and 3) those who are using an unsafe or unsuitable method. Included in the concept of unmet need are women who has mistimed or unwanted conception. The problems are that the survey questions regarding wantedness are biased and under-reported. Reported unplanned pregnancies and live births do not take into account abortions. The KAP surveys rarely ask for information on abortion; World Fertility Surveys tend to under-report voluntary abortion. There is a need to assess the need for safe, accessible, and affordable methods of pregnancy termination. Projections are that FP demand will rise sharply in most southern countries. national program strategies must be devoted to reducing the level of unmet need for the following women: 1) nonusers who are at risk of an unplanned pregnancy and need contraception; 2) users who need better contraceptive methods; 3) nonusers and users who need a safe, accessible method of pregnancy termination; and 4) nonusers and users who need more comprehensive sexual and reproductive health services. The current conventional method are useful only when limitations are noted clearly. Better measures, which expand the net of unmet need, will show the true extent of women and men's need for family planning formation and services.

Trends and Differentials in Breastfeeding Behaviour: Evidence from the WFS and DHS

In this paper trends and correlates of breastfeeding behaviour are analysed with data from available surveys conducted in conjunction with the World Fertility Surveys (WFS) and the Demographic and Health Surveys (DHS). Both these series of fertility surveys were designed and carried out in similar fashions, and in both, similar information on breastfeeding behaviour and its correlates was collected. Therefore, these data provide the best comparative information currently available. The first objective is to compare current-status information on breastfeeding with retrospective reports on durations of lactation. The extent to which distortions in retrospectively reported ages at weaning produce biases in summary measures (means and quartiles) of breastfeeding durations is examined, and the loss of precision incurred by the use of current-status data is explored. On the basis of these results, the relative merits of the two types of breastfeeding information are discussed. The second objective is to document breastfeeding differentials by education and urban/rural residence, in populations with surveys conducted as part of the WFS or the DHS. The third objective is to document trends in breastfeeding in populations with both WFS and DHS surveys. The results should prove useful in helping public-health officials to target campaigns to promote breastfeeding among those who would benefit most.

The Socio-Cultural Context of Family and Fertility in Sub-Saharan Africa

The conclusion reached in this examination of fertility and family formation patterns in sub-Saharan Africa is that researchers and policymakers cannot assume that a unique population program can be developed and be successful in all regions and cultures. Socioeconomic factors and cultural factors vary between and within regions. The effect of economic crisis and of AIDS transmission is unknown. Demographic transition theory has not effectively accounted for the lack of fertility decline in Africa. Mortality levels have declined but not fertility. Even with national family planning programs womens use of contraceptives is low. There is a persistent preference for large families. Research has recommended policies which emphasize female education in order to lower the demand for children. Womens groups and grass roots mobilization must be engaged to promote and implement family planning. Womens autonomy in decision making needs to be encouraged by programs; economic independence from husbands needs to be secured for women. An overview is provided of the theoretical framework of fertility. Discussion focuses on factors affecting fertility in sub-Saharan Africa: the impact on supply and demand factors from individual socioeconomic differences and the cultural context. Attention is also given to African reproductive trends African population policies and future recommendations and research needs. Africa has had the highest fertility in the world i.e. 6-7 children/woman. There are short breast-feeding durations and short postpartum abstinence periods. Rwanda has the highest fertility currently and Kenyas fertility has dropped from the distinction of being the highest. Population growth is the highest because of a decline in mortality. Data from the World Fertility Surveys and Demographics Surveys have helped to develop a more complex view of the interaction between demographic and economic factors and fertility decline. Proximate determinants have been identified. By 1984 most governments had developed explicit population policies on birth spacing and integrated programs with appeal to the educated and urban population.