The contribution of adolescents' childbearing to total fertility rates in many sub-Saharan African countries is higher than in other parts of the world. In this paper, data collected from 897 female adolescents aged 15–19 years are analysed to investigate patterns and determinants of entry into motherhood in two informal settlements in Nairobi, Kenya, using Kaplan–Meier estimates and Cox regression models. About 15% of these adolescents have had a child. The findings show that marriage, being out of school and having negative models in peer, family and school contexts are associated with early childbearing among females aged 15–17 years. For adolescents aged 18–19 years, school attendance considerably delays entry into motherhood while marriage hastens its timing. Furthermore, older adolescents with high levels of social controls (parental monitoring or perceived peer orientation to or approval of prosocial behaviours) and individual controls (high religiosity and positive orientation to schooling) are likely to delay childbearing. Programmes aiming to reduce risky sexual behaviours that could lead to childbearing among adolescents should be introduced very early, and before the onset of sexual activity. Also, the findings underscore the need to identify and address the risky factors and reinforce the protective ones in order to improve sexual and reproductive health outcomes of adolescent girls in Nairobi slum settlements.

Malaria is a major cause of under-five mortality in Mali and many other developing countries. Malaria control programmes rely on households to identify sick children and either care for them in the home or seek treatment at a health facility in the case of severe illness. This study examines the involvement of mothers and other household members in identifying and treating severely ill children through case studies of 25 rural Malian households. A wide range of intra-household responses to severe illness were observed among household members, both exemplifying and contravening stated social norms about household roles. Given their close contact with children, mothers were frequently the first to identify illness symptoms. However, decisions about care-seeking were often taken by fathers and senior members of the household. As stewards of the family resources, fathers usually paid for care and thus significantly determined when and where treatment was sought. Grandparents were frequently involved in diagnosing illnesses and directing care towards traditional healers or health facilities. Relationships between household members during the illness episode were found to vary from highly collaborative to highly conflictive, with critical effects on how quickly and from where treatment for sick children was sought. These findings have implications for the design and targeting of malaria and child survival programming in the greater West African region.

Survey data on contraceptive use for about 80 countries are related to measures of contraceptive access, by method, from 1999 to 2009. Cross-tabulation and correlational methods are employed, with geographic comparisons and time trends. Total prevalence of use for five modern contraceptive methods correlates well to a variety of access measures. Greater access is also accompanied by a better balance among methods for both access and use. Sub-Saharan African countries show similar patterns though at lower levels. Improved access to multiple methods is consistently associated with higher levels of contraceptive use.

The majority of studies of the birth spacing–child survival relationship rely on retrospective data, which are vulnerable to errors that might bias results. The relationship is re-assessed using prospective data on 13,502 children born in two Nairobi slums between 2003 and 2009. Nearly 48% were first births. Among the remainder, short preceding intervals are common: 20% of second and higher order births were delivered within 24 months of an elder sibling, including 9% with a very short preceding interval of less than 18 months. After adjustment for potential confounders, the length of the preceding birth interval is a major determinant of infant and early childhood mortality. In infancy, a preceding birth interval of less than 18 months is associated with a two-fold increase in mortality risks (compared with lengthened intervals of 36 months or longer), while an interval of 18–23 months is associated with an increase of 18%. During the early childhood period, children born within 18 months of an elder sibling are more than twice as likely to die as those born after an interval of 36 months or more. Only 592 children experienced the birth of a younger sibling within 20 months; their second-year mortality was about twice as high as that of other children. These results support the findings based on retrospective data.

The prevalence of consanguinity in eight provinces of Afghanistan has recently been reported by Saify & Saadat (2012). The present cross-sectional study was done in order to illustrate the prevalence and types of consanguineous marriages among other populations of Afghanistan. Data on types of marriages were collected using a simple questionnaire. The total number of couples in this study was 5200 from the following provinces: Farah, Ghazni, Herat, Hilmand, Kabul, Kandahar, Logar, Parwan and Wardak. Consanguineous marriages were classified by the degree of relationship between couples: double first cousins, first cousins, first cousins once removed, second cousins and beyond second cousins. The coefficient of inbreeding (F) was calculated for each couple and the mean coefficient of inbreeding (α) estimated for each population. The α in the country was 0.0226, ranging from 0.0203 in Farah province to 0.0246 in Herat province. There were significant differences between provinces for frequencies of different types of marriages (p<0.001). First cousin marriages (21.7%) were the most common type of consanguineous marriages, followed by second cousins (16.0%), first cousins once removed (14.0%), beyond second cousins (6.9%) and double first cousins (1.6%). There was significant difference between ethnic groups for the types of marriages (p<0.001). Tajiks (Soni) and Sadats showed the lowest (α=0.0215) and highest (α=0.0242) levels of consanguinity among ethnic groups in Afghanistan, respectively. The present study shows that the Afghani populations, the same as other Islamic populations, have high levels of consanguinity.

This study uses Swedish occupational register data to examine whether the proportion of men in administrative workplaces in the Swedish public service affects all-cause mortality risks amongst both males and females of working age. Using piecewise constant survival models to analyse occupational data from the Swedish administrative registers from 1995 to 2007, it was found that for males, a 1% increase in the proportion of males was associated with a 1.3% increase in mortality risk (hazard ratio, HR 1.013, 95% CI 1.007–1.020, p<0.001), but no association was found for females (HR 1.004, 95% CI 0.996–1.012, p=0.297). Adjustments were made for age, family status, education, occupational status, occupational segregation by sex, the total number of individuals in the workplace, level of government, region, period and variables reflecting the workplace structure by age, age by sex, occupation and education. A higher proportion of males may be related to (i) an increased exposure to risky health behaviours such as alcohol consumption and unhealthy dietary patterns, (ii) a tendency towards sickness presenteeism, and (iii) an increase in the levels of several well-established emotional stressors in the workplace, leading to an increased level of psychosocial stress. The findings and potential extensions of this research are discussed.

During famines females generally have a mortality advantage relative to males, and the highest levels of mortality occur in the very young and the elderly. One popular hypothesis is that the sex differential in mortality may reflect the greater body fatness combined with lower metabolism of females, which may also underpin the age-related patterns of mortality among adults. This study evaluated the ‘body fat’ hypothesis using a previously published and validated mathematical model of survival during total starvation. The model shows that at a given body weight females would indeed be expected to survive considerably longer than males in the absence of food. At a mass of 70 kg for example a female aged 30 would survive for 144 days compared with life expectancy of only 95 days for a male of the same age and weight. This effect is contributed to by both the higher body fatness and lower metabolism of the females at a given body weight. However, females are generally smaller than males and in addition to a sex effect there was also a major effect of body size – heavier individuals survive longer. When this body size effect was removed by considering survival in relation to BMI the sex effect was much reduced, and could be offset by a relatively small difference in pre-famine BMI between the sexes. Nevertheless, combining these predictions with observed mean BMIs of males and females across 48 countries at the low end of the obesity spectrum suggests that in the complete absence of food females would survive on average about 40% longer (range 6 to 64.5%) than males. The energy balance model also predicted that older adult individuals should survive much longer than younger adult individuals, by virtue of their lower resting metabolic rates and lower activity levels. Observations of the female survival advantage in multiple famines span a much wider range than the model prediction (5% to 210%). This suggests in some famines body fatness may be a significant factor influencing the mortality differential between the sexes, but in other famines other factors are likely to be more important. Moreover, the pattern of mortality in relation to age is completely opposite that predicted. These data emphasize the complex nature of famine mortality and suggest that a simple model of energy utilization alone is inadequate to explain the major aspects of this phenomenon.

A detailed database on the genealogy of the Makarska region in Croatia has been created. The twinning rate for three villages in the region (Podgora, Tučepi and Brela) were analysed over the period 1870 to 1940 and factors such as mother's age and birth order are discussed. Of the three villages, Podgora was identified as having the highest twinning rate and consequently records for Podgora were examined further to include almost 400 years of historical data (from 1621 to 1950).

This paper investigates whether ethnic diversity at the Demographic and Health Surveys (DHS) cluster level predicts HIV serostatus in three sub-Saharan African countries (Kenya, Malawi and Zambia), using DHS household survey and HIV biomarker data for men and women aged 15–59 collected since 2006. The analysis relates a binary dependent variable (HIV positive serostatus) and a weighted aggregate predictor variable representing the number of different ethnic groups within a DHS Statistical Enumeration Area (SEA) or cluster, which roughly corresponds to a neighbourhood. Multilevel logistic regression is used to predict HIV prevalence within each SEA, controlling for known demographic, social and behavioural predictors of HIV serostatus. The key finding was that the cluster-level ethnic diversity measure was a significant predictor of HIV serostatus in Malawi and Zambia but not in Kenya. Additional results reflected the heterogeneity of the epidemics: male gender, marriage (Kenya), number of extramarital partners in the past year (Kenya and Malawi, but probably confounded with younger age) and Muslim religion (Zambia) were associated with lower odds of positive HIV serostatus. Condom use at last intercourse (a spurious result probably reflecting endogeneity), STD in the past year, number of lifetime sexual partners, age (Malawi and Zambia), education (Zambia), urban residence (Malawi and Zambia) and employment (Kenya and Malawi) were associated with higher odds of positive serostatus. Future studies might continue to employ multilevel models and incorporate additional, more robust, controls for individual behavioural risk factors and for higher-level social and economic factors, in order to verify and further clarify the association between neighbourhood ethnic diversity and HIV serostatus.