Contraceptive prevalence surveys from sub-Saharan Africa typically show low rates of method use. The current study of one zone in Kinshasa, Zaïre, provides a more detailed view of fertility control in an urban population by examining the relative duration of breast-feeding, amenor-rhoea and sexual abstinence during the post-partum period. While motivations to prevent pregnancy remain high until the youngest child is over 24 months, the average duration of abstinence is only 4 months. This paper describes the methods women use to avoid pregnancy and the changes over the post-partum period.

This paper examines the effects of age at marriage and differential mortality of males and females on the incidence of widowhood between the sexes. Abridged life tables constructed from marital status and death registration data of a rural area of Bangladesh for the period 1974–79 were used. The difference in life expectancy between males and females varies from 0·4 to 2·2 years at the ages 0 to 65 years and over. The mortality differentials show that the probabilities of a male or a female surviving the other spouse would be approximately the same, were there no other influence. But the incidence of widows is about ten times that of widowers. Other relevant factors, under a given regime of mortality, are age at marriage and age difference between husband and wife.

Data from the 1985–86 Japanese census are analysed to explore the determinants of the divorce rates in Japan's forty-seven prefectures, using two theoretical models: (a) the social integration model, which is shown to have a greater utility in predicting Japanese divorce levels than (b), the human capital model. Female emigration patterns play a significant role in affecting the divorce rate. Population increase and net household income are also important predictors of the Japanese divorce rate and urbanization has a great influence in modern Japan. Demographic and aggregate variables such as migration, urbanization, and socioeconomic factors are useful when organized under a social integration model.

This study of the relationship between mortality risks of siblings born to the same mother shows that, in Bangladesh, the death of the immediately preceding sibling in its infancy has a negative influence on the survival chance of the child in question in its infancy; however, death of the preceding sibling appears to have a positive influence on the index child's survival at ages 1–5 years. Similar results are found for the survival status of the two preceding siblings. Preceding birth interval length and survival status and sex of the immediately preceding sibling are also significant predictors of child mortality between ages 1 and 5 years. Possible explanations may be that the index child faces stronger competition from its immediately preceding brother than from its immediately preceding sister, or that the index child is likely to be looked after more by its preceding sister than by its preceding brother.

From 1 January 1981 to 31 December 1982 information on all births to Bedouin Arab women residing in the Negev Desert of Israel showed a previously unreported seasonal pattern. The peak season, November-February, coincided with the period of cool temperatures and the Bedouin Arab cultural seasons of winter and spring. This pattern is different from those of Jewish and Christian groups in the same region, a difference not attributable to religion alone.

Sociodemographic factors associated with the peak season of birth include traditional occupations of fathers, multiparae 2+, and traditional place of residence. This pattern has persisted over the past 15 years although it is less apparent among the more recently sedentarized Bedouin Arabs.

In 1984 a prospective study of 1645 women and 1677 births in a rural community in north-eastern Brazil showed the infant mortality rate to be 65 per 1000 live births. Neonatal, post-neonatal and infant mortality are analysed to determine the most important risk factors for each period. Post-neonatal survival depends largely on factors relating to child care, while neonatal deaths are more likely to be associated with biological factors. The principal cause of death, diarrhoeal disease, was responsible for a third of the deaths.

About 10% of 3887 ever-married women included in the 1984–85 Malaysian Population and Family Survey revealed that they were influenced by the new population policy to desire more children than they had originally wanted. These women were more likely to be rural Malays from the lower socioeconomic class. Ideal family size was more than four children. Children are desired for economic benefits and emotional support. The natality of the Malays has risen since 1980: their total fertility rate has increased while their contraceptive prevalence rate has dropped sharply. Coupled with a decline in the crude death rate, the present fertility preferences and behaviour of the Malays will render the target of the population policy more attainable than is reflected by the survey data.

This paper examines mortality by cause of death in a rural area of Machakos district in Kenya. The cause-of-death data collected between 1975 and 1978 were likely to be of fairly good quality. The number of deaths was higher among infants and children. Infectious diseases and diseases of the respiratory system were the leading causes of death among children below 5 years of age. Next in prominence were the causes ascribed to congenital anomalies and perinatal conditions.

Among adolescents and young adults, injury and poisoning, together with tuberculosis and other infectious and parasitic diseases, were the leading causes of death. Degenerative diseases, especially diseases of the circulatory system and neoplasms and respiratory illness, were responsible for the majority of deaths among the older population.

Data from a 1985 survey in two major population centres in Southern Sudan, Juba and Wau, were analysed in order to assess childhood mortality levels and the effect of UNICEF's health care programme. There are continuing high levels of childhood mortality. Logistic regression analysis shows significant positive associations between child survival and immunization, oral rehydration therapy and maternal education.

This paper describes the origins and size of the Muslim population in Australia, at present about 1% of the total population. Their age distribution is younger and their sociodemographic characteristics are different from those of the rest of the Australian population.

Different methods of obtaining information in medical and social research present problems of interpretation for the researcher. However, there are few systematic studies on the extent of the lack of concordance yielded by different methods. This paper uses data from a randomized controlled trial of social support in pregnancy to examine this issue in relation to three methods of data collection—medical records, home interviews and a postal questionnaire—on the following topics: obstetric history; smoking, alcohol use, number of antenatal hospital visits, bleeding and depression in pregnancy; length of labour; baby's sex, birthweight and neonatal health problems; and ethnicity. Considerable discrepancies are found comparing the different data sources. These suggest that mothers may be more reliable sources of information than medical records, and that the anonymity of a postal questionnaire may provide higher estimates than home interviews on some sensitive topics, such as smoking in pregnancy.

Recent data from Bangladesh reveal evidence of some fertility decline. Although fertility increased among younger age groups between 1975 and 1983, it was offset by a decrease in fertility in the older age groups, resulting in a slight overall decrease in total fertility in 1983. Fertility was lower among urban residents, educated mothers and contraceptive users than among rural residents, uneducated mothers and contraceptive non-users, respectively, particularly in 1983.

The influence of some household and maternal variables on three anthropometric nutritional status indices of hospitalized children in Addis Ababa, Ethiopia, are examined. On admission, only 30% of these children can be classified as being of a normal overall nutritional status. There are no significant differences in weight-for-age of hospitalized children between those residing in Addis Ababa and those residing in the rural areas. Income and father's occupation appear to be the major household factors influencing the level of two of the three indices (weight-for-age and weight-for-height). Length of last closed birth interval and, to a lesser degree, maternal age appear to have significant effects on all three nutritional status indices. Upon admission to hospital, children who will in the end survive their hospital stay are on average nutritionally normal or in a mild state of malnutrition, whereas children who will die during their stay arrive in a moderate or severe state of malnutrition. The degree of malnutrition is positively related to the risk of mortality in respiratory disease patients.

Evidence on infant weaning processes provided by field research in Addis Ababa, Ethiopia, and among a refugee population of Eritreans in the Sudan is presented. The study in Addis Ababa, where households were economically disadvantaged but the situation was nutritionally stable, allowed the identification of factors constraining weaning, which includes both the introduction of supplementary foods and the termination of breastfeeding. While the timing of each aspect of weaning was the outcome of the interaction between mother and infant factors, ‘infant-centred’ factors were more important in the commencement and ‘mother-centred’ factors in the completion of weaning. The refugee population had in normal times a similar weaning regime, but under the unstable conditions of flight and life in a refugee camp the process had been significantly altered. Investigation of the factors which have led to altered weaning processes elaborates and confirms the model derived from the Addis Ababa study.

This paper examines factors influencing endogamy in a Dogon population in Mali. Situated in Boni district, this population of about 5000 individuals is distributed over fifteen villages located on four independent massifs. This population is strongly endogamous (only 4% of all marriages are contracted with neighbouring ethnic groups), and each massif shows high endogamy. The roles of lineage, residence in the same village, and geographical distance in mating choice are examined. These different factors are successively analysed using log-linear statistical models and the results offer a more precise interpretation of endogamy in this population.

The effects of frequency of intercourse on perceptions of two of the most widely used contraceptive methods, the pill and condom, were assessed in 128 female college students currently involved in a sexual relationship. Intercourse frequency was found to be strongly associated with knowledge of both methods. People experiencing more frequent sexual intercourse were more favourably disposed towards the pill and less towards the condom than people experiencing intercourse less frequently. Implications of these results are discussed.

In a comparative study to examine the effect of social factors on human twinning, data on sociodemographic and other factors were collected from parents of all twins born alive in Denmark in 1984 or 1985 and from a random sample of parents of singleton infants born in the same years. A postal questionnaire was used. The twins were classified as monozygotic (MZ) or dizygotic (DZ) twins by the similarity method. A trend was found in DZ-twinning, with significantly fewer DZ-twins born in the lower social classes, but not in MZ-twinning. All results were controlled for maternal age and parity.

The reproductive pattern of a sample of nuclear families from La Alpujarra (Andalusia, Spain) is analysed. The origin of the wife or consanguinity of the couple does not influence fertility. Variability in number of pregnancies is most closely associated with marriage duration followed by the wife's year of birth. Differences in the number of births are explained more by the number of pregnancies than by the number of miscarriages. The number of survivors to the first birthday is dependent on the number of births and to a lower extent on infant mortality. Data from incomplete families show that reproductive performance of the wife below the age of 45 cannot be accepted as a reliable estimate of complete reproduction.

Differences in fertility between the three major ethnic groups (Malays, Chinese and Indians) in Peninsular Malaysia and Singapore have existed since before the onset of fertility decline in the late 1950s and remain today, although the relative positions and the actual differences have changed due to the varying rates of decline. By 1987, the Malays experienced the highest fertility and the Chinese the lowest in both countries but in Singapore the Malay fertility was lower than the Chinese fertility in Peninsular Malaysia. The fertility differentials will lead to changes in the ethnic composition in both countries but more so in Peninsular Malaysia.

This paper analyses the socioeconomic and health care determinants responsible for the decline over the last two decades in infant mortality in Kuwait. Published data and the results of a national health survey conducted in 1984–85 show the following. With the overall affluence of the society, health care in terms of immunization has improved dramatically and more than 90% of all children are covered. Of all births, 99% now occur in a hospital or clinic. About half of the mothers continue to breast-feed their babies for about 16 months. Despite these favourable conditions, differences still exist between social classes. The risk of stillbirth remains much higher among the poorer women, those without any education and those who gave birth at home. These findings are consistent with developed countries like the USA and Japan, where the social class differences in mortality still persist.