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The study investigates sex differences in the prevalence of undernutrition in sub-Saharan Africa. Undernutrition was defined by Z-scores using the CDC-2000 growth charts. Some 128 Demographic and Health Surveys (DHS) were analysed, totalling 700,114 children under-five. The results revealed a higher susceptibility of boys to undernutrition. Male-to-female ratios of prevalence averaged 1.18 for stunting (height-for-age Z-score Z-score Z-score Z-scores

Background: The mean age at menarche remains poorly documented in Africa. Aim: To document levels, trends, and determinants of mean age at menarche in selected African populations. Subjects and methods: The World Fertility Surveys recorded the age at menarche in 12 African countries. These surveys were conducted from 1977 to 1983 and were based on large representative samples of national populations. Demographic and Health Surveys provided trends in adult height for the same cohorts. Results: The mean age at menarche was higher in sub-Saharan Africa (14.5 years) than in North-Africa (13.5 years). Age at menarche was declining significantly in all sub-Saharan African countries, but only in one North-African country. The speed of decline in sub-Saharan Africa averaged 0.47 years for a 30-year period, comparable to the speed of decline in Europe. Sub-Saharan African countries with higher increase in female adult height also had larger declines in mean age at menarche. In multivariate analysis, trends in age at menarche were correlated with trends in adult height and child survival. Conclusion: In sub-Saharan Africa, age at menarche was undergoing a transition similar to that of European countries in the nineteenth century and was associated with improving health of young women. North-African countries were more advanced.

Objective:To investigate trends in child anthropometry in Senegal between 1990 and 2015 and relate them with potential causes. Several hypotheses were tested: changes in health status, income, diet and socio-economic status.Design:Statistical analysis of trends in anthropometric data: height, weight, BMI and associated Z-scores calculated with the CDC-2000 standard (Centers for Disease Control and Prevention): height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ). Trends were fitted with linear regression models and were related with changes in health and socio-economic status.Setting:Nine nationally representative samples of Senegalese children aged 12–59 months, taken between 1986 and 2017 by Demographic and Health Surveys (DHS).Participants:Children aged 12–59 months.Results:Over the 25 years of investigation, the average height of children increased by +1·88 cm, their average weight by +0·10 kg, but their BMI decreased by −0·53 kg/m2. Corresponding changes expressed in Z-scores were +0·454 in HAZ, +0·109 in WAZ and −0·302 in WHZ. This pattern of decreasing stunting while increasing wasting was correlated with decreasing child mortality, despite small changes in income per capita and in adult heights or BMI. Largest improvements in HAZ were among the lower socio-economic strata, while largest declines in WHZ were among higher socio-economic strata.Conclusions:Decline in stunting appeared associated primarily with the control of infectious diseases, also responsible for the mortality decline. Increase in wasting was surprising. It appears associated with small changes in income per capita, and therefore in diet, in a context of increasing height.

Age at menarche was investigated using data collected from demographic surveys (WFS, DHS) conducted in Nigeria between 1982 and 2018, all of which were based on large representative samples of the female population. Linear-logistic regressions were used to estimate mean age at menarche, its trends and its risk factors. Mean age at menarche had underwent a marked secular decline from 15.02 years for girls born in 1933 to 13.78 years for girls born in 2003. In multivariate analysis, height (stature), body mass index (BMI), level of education and household wealth had independent effects on age at menarche, whereas urban residence had no effect. Socioeconomic gradients were large: +9 years of schooling was associated with a –0.52 year decrease in age at menarche, and +2 standard deviations in household wealth with a –0.33 year decrease. The impact of anthropometry was even greater: +2 standard deviations in height was associated with a –0.99 year decrease in age at menarche, and +2 standard deviations in BMI with a –1.42 year decrease. Northern provinces had a higher mean age at menarche than southern provinces. Compared with independent sources, long-term trends in age at menarche, as well as their fluctuations, appeared to be correlated with trends and fluctuations in income per capita and in under-five mortality, but not with divergent trends in adult height.

BackgroundExcess male morbidity and mortality is well recognised in neonatal medicine and infant health. In contrast, within global nutrition, it is commonly assumed that girls are more at-risk of experiencing undernutrition. We aimed to explore evidence for any male/female differences in child undernutrition using anthropometric case definitions and the reasons for differences observed.MethodsWe searched: Medline, Embase, Global health, Popline and Cochrane databases with no time limits applied. Eligible studies focused on children aged 0-59 months affected by undernutrition where sex was reported. In the meta-analysis, undernutrition-specific estimates were examined separately for wasting, stunting and underweight using a random effects model.Results76 studies were identified: 46/76 studies were included in the meta-analysis. In 20 which examined wasting, boys had higher odds of being wasted than girls (pooled OR 1.26, 95% CI 1.13-1.40). 39 examined stunting: boys had higher odds of stunting than girls (pooled OR 1.31 95% CI 1.24-1.39). 25 explored underweight: boys had higher odds of being underweight than girls (pooled OR 1.19, 95% CI 1.07-1.32). There was some limited evidence that the female advantage indicating lower risk of stunting and underweight was weaker in South Asia than other parts of the world.44/76 (58%) studies discussed possible reasons for boy/girl differences; 11/76 (14%) cited studies with similar findings with no further discussion; 21/76 (28%) had no sex difference discussion. 6/44 studies (14%) postulated biological causes, 21/44 (48%) social causes and 17/44 (38%) to a combination.ConclusionOur review indicates that undernutrition in children under 5 is more likely to affect boys than girls, though the magnitude of these differences varies and is more pronounced in some contexts than others. Future research should further explore reasons for these differences and implications for nutrition policy and practice.Key QuestionsWhat is already known?Undernutrition (wasting, stunting, and underweight) is a public health problem affecting millions of children aged under 5 years globally.Although higher neonatal and infant morbidity/mortality for boys is well described, little attention has been given to sex differences in the field of undernutrition due to an assumption that girls are very often disadvantaged over boys.What are the new findings?In most settings studied, undernutrition is more common among boys than girls, though the extent of these differences varies and is reversed in a few contexts.Both biological and social mechanisms have been proposed to be responsible for the observed differences as well as a combination of the two.What do the new findings imply?Greater awareness of actual sex differences is needed within the field of nutrition. While sex-specific data is routinely analysed and reported in nutrition surveys it should be used in nutrition programming to better identify and understand what differences exist. Analysis should assess if the sex balance in programme admissions is reflective of the population undernutrition burden.Further research is needed to understand the mechanisms that lead to sex and gender differences in undernutrition and their implications. Better epidemiological understanding is a priority, as is work to explore their consequent effects on morbidity and mortality.

The study analysed the HIV/AIDS situation in Zambia six years after the onset of mass campaigns of Voluntary Medical Male Circumcision (VMMC). The analysis was based on data from Demographic and Health Surveys (DHS) conducted in 2001, 2007 and 2013. Results show that HIV prevalence among men aged 15–29 (the target group for VMMC) did not decrease over the period, despite a decline in HIV prevalence among women of the same age group (most of their partners). Correlations between male circumcision and HIV prevalence were positive for a variety of socioeconomic groups (urban residence, province of residence, level of education, ethnicity). In a multivariate analysis, based on the 2013 DHS survey, circumcised men were found to have the same level of infection as uncircumcised men, after controlling for age, sexual behaviour and socioeconomic status. Lastly, circumcised men tended to have somewhat riskier sexual behaviour than uncircumcised men. This study, based on large representative samples of the Zambian population, questions the current strategy of mass circumcision campaigns in southern and eastern Africa.

The study describes the patterns of concurrent wasting and stunting (WaSt) among children age 6–59 months living in the 1980s in Niakhar a rural area of Senegal under demographic surveillance. Wasting and stunting were defined by z scores lower than -2 in weight for height and height for age. Both conditions were found to be highly prevalent wasting more so before age 30 months stunting more so after age 30 months. As a result concurrent WaSt peaked around age 18 months and its prevalence (6.2%) was primarily the product of the two conditions with an interaction term of 1.57 (p < 10-6). The interaction was due to the correlation between both conditions (more stunting if wasted more wasting if stunted). Before age 30 months boys were more likely to be concurrently wasted and stunted than girls (RR = 1.61) but the sex difference disappeared after 30 months of age. The excess susceptibility of younger boys could not be explained by muscle mass or fat mass measured by arm or muscle circumference triceps or subscapular skinfold. Concurrent WaSt was a strong risk factor for child mortality and its effect was the product of the independent effect of each component with no significant interaction. Key messages: 1) Prevalence of concurrent wasting and stunting (WaSt) among under-five children is the product of independent wasting and stunting plus an interaction term of 57%. Prevalence of WaSt peaks around age 18 months; 2) Prevalence of WaSt is about 50% higher among boys than among girls before age 30 months largely because their higher susceptibility to stunting but not higher thereafter; and 3) Excess mortality associated with WaSt is the product of that associated with wasting and that associated with stunting.

The study documents cases of extremely high fertility in sub-Saharan Africa. The DHS surveys were used for the analysis, with straightforward calculations of period and cohort fertility. Two case studies were further analysed: Kenya (1965-69) and Niger (1982-86). In both cases, total fertility in rural areas reached 9 children per woman, as high as among the Hutterites of North-America (1921-1940). However, the complete family size never exceeded 8.0 children per woman in Kenya (cohorts 1939-1946) and 8.2 children per woman in Niger (cohorts 1960-1967). Compared with the Hutterites, in both African countries the age pattern of fertility was earlier and with a lower mode, age at marriage was earlier, birth intervals were longer because of long breastfeeding, and secondary infertility was more frequent after the 5th birth. Other proximate determinants of fertility appeared similar in the three populations, with the probable exception of health and nutritional status. Implications for modelling are discussed.

SummaryThis study analysed sex ratios at birth (defined as the number of male births per 100 female births) using data on children ever-born from three censuses conducted in Ethiopia in 1984, 1994 and 2007. The results showed very high values by any standard, with an average of 108.4 for a sample of some 8.2 million births, with somewhat lower values in urban areas. Analysis of socioeconomic correlates revealed that the sex ratio varied very much by household wealth, from about 110 for very poor women to about 102 for wealthier women. The high value of the sex ratio at birth in Ethiopia could be explained by poverty, used as a proxy for poor nutritional status. In multivariate analysis, the effects of living in urban areas and of maternal education were less important than household wealth. Among the many ethno-linguistic groups, the Nilotic family had higher sex ratios than other groups. The results were confirmed using data from DHS surveys conducted in the country, and by the analysis of children still living at time of census.

Background : Completeness of vital registration remains very low in sub-Saharan Africa, especially in rural areas. Objectives : To investigate trends and factors in completeness of birth and death registration in Agincourt, a rural area of South Africa covering a population of about 110,000 persons, under demographic surveillance since 1992. The population belongs to the Shangaan ethnic group and hosts a sizeable community of Mozambican refugees. Design : Statistical analysis of birth and death registration over time in a 22-year perspective (1992–2014). Over this period, major efforts were made by the government of South Africa to improve vital registration. Factors associated with completeness of registration were investigated using univariate and multivariate analysis. Results : Birth registration was very incomplete at onset (7.8% in 1992) and reached high values at end point (90.5% in 2014). Likewise, death registration was low at onset (51.4% in 1992), also reaching high values at end point (97.1% in 2014). For births, the main factors were mother’s age (much lower completeness among births to adolescent mothers), refugee status, and household wealth. For deaths, the major factors were age at death (lower completeness among under-five children), refugee status, and household wealth. Completeness increased for all demographic and socioeconomic categories studied and is likely to approach 100% in the future if trends continue at this speed. Conclusion : Reaching high values in the completeness of birth and death registration was achieved by excellent organization of the civil registration and vital statistics, a variety of financial incentives, strong involvement of health personnel, and wide-scale information and advocacy campaigns by the South African government. Keywords: completeness of vital registration; demographic surveillance system; socioeconomic factors; level of education; household wealth; Mozambican refugee; South Africa; Agincourt (Published: 24 October 2016) Citation: Glob Health Action 2016, 9 : 32795 - http://dx.doi.org/10.3402/gha.v9.32795

The study uses data from eight censuses conducted between 1970 and 2011 to reconstruct long term trends in terminal celibacy in South Africa. The cohort analysis covers those born between 1870 and 1971. Results show a quasi-stable prevalence of terminal celibacy for cohorts born before 1920, followed by a steep rise. Levels and trends were notably different for the four population groups. Black/Africans had the highest level at endpoint (50% celibate), despite lower levels at onset, followed by Coloured (34%). Indian/Asian had the lowest level at endpoint (14%). White/European had highest levels at onset, and intermediate values at endpoint (17%). Differences were large by ethnicity, Zulu and Swazi having the highest prevalence of terminal celibacy (60%). Correlations with development were complex, with higher values among persons with lower education, and those living in urban areas, and lower values among those who were employed. Overall, cultural factors dominated the rise in terminal celibacy in South Africa.

The study presents an analysis of long-term trends in terminal celibacy and primary infertility in South Africa. Sources of data were four population censuses conducted in 1996, 2001, 2007 and 2011, which cover cohorts of women born between 1900 and 1971 (women age 40 years and above at time of census). Terminal celibacy was defined as not being married, widowed or divorced at time of census. Primary infertility was defined as not having had any live birth at time of census. Results showed complex dynamics of both infertility and celibacy. Infertility first declined for cohorts born before 1940 then increased. Celibacy first declined for cohorts born before 1920, then increased. All dynamics varied by population group, by ethnic group, by area of residence, by province of residence, and by level of education. A multivariate analysis indicated that being never-married was the most important factor of infertility, explaining about half of cases. Dynamics of marriage and infertility are discussed in light of the complex population history of the country in the 20 th century. Cultural factors appear critical for explaining levels and trends of celibacy and infertility, far above any socio-economic factor.

Demographic surveys and censuses often record pregnancy-related deaths, defined as those occurring during the maternal risk period (pregnancy, delivery, and six weeks postpartum), but do not include cause of death. This study presents a method for estimating obstetric mortality from pregnancy-related deaths data. Calculations are based on multiple-decrement life tables, and data needed are simply age-specific fertility and mortality rates that are commonly available in Demographic and Health Survey (DHS) or census data, and an estimate of the relative risk of death from nonobstetric causes during the maternal risk period. The method is tested on 59 DHS surveys from Africa. Results show that, on average, less than half of the pregnancy-related deaths are attributable to obstetric causes. This proportion varies with the level of mortality and fertility, and in particular with the prevalence of HIV in the population.

The World Health Organization and UNICEF define non-oedematous severe acute malnutrition (SAM) either by a mid-upper arm circumference (MUAC) less than 115 mm or by a weight-for-height z-score (WHZ) less than -3. The objective of this study was to assess whether there was any benefit to identify malnourished children with a high risk of death to combine these two diagnostic criteria. Data of a longitudinal study examining the relationship between anthropometry and mortality in rural Senegal and predating the development of community-based management of SAM were used for this study. First, the receiver operating characteristic (ROC) curves of MUAC and of WHZ to predict mortality were drawn, and then the points corresponding to WHZ less than -3 and/or MUAC less than 115 mm were positioned in relation to these curves. MUAC had the highest ROC curve, which indicates that it identifies high-risk children better than WHZ. Both points representing WHZ less than -3 and/or MUAC less than 115 mm were below the MUAC ROC curve. It is concluded that to identify high-risk malnourished children, there is no benefit in using both WHZ less than -3 and/or MUAC less than 115 mm, and that using MUAC alone is preferable.

SummaryIn this study, sex ratios at birth (male/female births) were found to vary according to family composition. Using Demographic and Health Survey (DHS) maternity histories from sub-Saharan Africa, the study shows that the sex ratio at birth increases with the number of previous male births and decreases with the number of previous female births. For families with only males, the sex ratio increases from 1·046 for the first birth to 1·083 for the 8th birth. For families with only females, the sex ratio decreases from 1·046 for the first birth to 0·942 for the 8th birth. The differences were highly significant when tested with a linear logistic model (p=0·018 for males; p=1·85✕10−11 for females). The effect was not symmetrical, and was found to be significantly stronger for females. These effects could be reproduced assuming a strong heterogeneity between couples. The distribution of sex ratios was fitted with an asymmetrical log-gamma function, which revealed a wide range of variation in the sex ratio between 0·50 and 1·30, and a peak around 1·14. The results and their implications are discussed in the light of former findings in France and in the United States of America.

The study analyses the profile and the behavior of male clients of female commercial sex workers (CSW's) in Zambia. According to the Zambia 2001 DHS survey, among the 1730 men sexually active during the past year, the pro- portion who used the services of CSW's in the 12 months prior to the survey was 13.2%. This proportion varied very much with age and marital status. Most clients of CSW's were unmarried men. Several demographic, socioeconomic, and personal factors were identified, which effect differed according to marital status. Using the services of CSW's appears as a very heterogeneous behavior, with major differences according to age, marital status, socioeconomic status, and per- sonal attitudes. A multiple correspondence analysis revealed that attitudes (drinking, smoking, wife-beating) were or- thogonal to age, marital status and socioeconomic status. The frequency of visits to CSW's was fitted with a Poisson model. On the average, clients visited CSW's 3.8 times a year.

This paper examines the complex relationship between male circumcision and HIV prevalence and incidence in sub-Saharan African countries that have generalised epidemics. In South Africa, the mean yearly HIV incidence and an estimate of the net reproduction rate of the epidemic (R0) (in this case, the ratio of the number of HIV-infected persons between 1994 and 2004 to the number of persons infected in 1994 from which they were presumed to have become infected) were computed from antenatal clinic data for the period 1994–2004, and then compared, by province, to prevailing levels of male circumcision (high, medium and low). In South Africa, mean yearly HIV incidence and net reproduction rate of the epidemic were not lower in provinces with higher levels of male circumcision. For thirteen other countries where Demographic and Health Survey data were available, male HIV prevalence in circumcised and non-circumcised groups was compared. A meta-analysis of that data, contrasting male HIV seroprevalence according to circumcision status, showed no difference between the two groups (combined risk ratio [RR] = 0.99, 95% CI = 0.94–1.05). Individual case study analysis of eight of those countries showed no significant difference in seroprevalence in circumcised and uncircumcised groups, while two countries (Kenya and Uganda) showed lower HIV prevalence among circumcised groups, and three countries (Cameroon, Lesotho and Malawi) showed higher HIV prevalence among circumcised groups. In most countries with a complex ethnic fabric, the relationship between men's circumcision status and HIV seroprevalence was not straightforward, with the exception of the Luo in Kenya and a few groups in Uganda. These observations put into question the potential long-term effect of voluntary circumcision programmes in countries with generalised HIV epidemics. Keywords: demography; epidemiology; HIV infection; household surveys; meta-analysis; prevention and control; quantitative data; statistical analysisAfrican Journal of AIDS Research 2008, 7(1): 1–8

Background The HIV seroprevalence among women aged 15–24 years was compared according to their pattern of contraceptive use in four African countries: Kenya, Lesotho, Malawi and Zimbabwe. Study Design Data were derived from Demographic and Health Surveys (DHS) conducted between 2003 and 2006 on representative samples, totaling 4549 women. Results It is indicated that users of depo-medroxyprogesterone acetate (DMPA) have a significantly higher seroprevalence than nonusers [odds ratio (OR)=1.82, 95% CI=1.63–2.03] and higher than users of oral contraceptives and users of traditional methods. The results were confirmed in a multivariate analysis including as controls, age, duration since first intercourse, urban residence, education, number of sexual partners in the last 12 months and marital status. A somewhat smaller net effect (OR=1.34, 95% CI=1.10–1.63) was found. In contrast, oral contraceptives and traditional methods did not show any risk for HIV (OR=0.96 and 0.92, respectively). Conclusion The increased risk of DMPA was present in three of the four countries investigated, and significant in Zimbabwe and Lesotho, the countries with the highest HIV seroprevalence. The HIV risk attributable to DMPA remained small altogether and was estimated as 6% in the four countries combined.

Before 1965, under-five mortality was declining in Rwanda, from an estimated value of 346 per 1,000 in 1950 to 229 per 1,000 in 1965. Then it rose for about 12 years to 261 per 1,000 in 1977, to decline again, reaching a level of 132 per 1,000 in 1990. The 1991–2000 period witnessed a major peak of mortality in 1994 and another peak in 1998. This paper explores reasons for these significant changes in mortality. The 1965–77 period was marked by severe difficulties after independence in 1962, due to the sudden departure of expatriates, the relative international isolation, the lack of international aid, the flight of educated persons of Tutsi origin, and possibly the departure of herders and their cattle following ethnic conflicts between Hutu and Tutsi during the 1959–66 period. During the 1977–90 period, social indicators became more favourable, with the increasing benefits from earlier social investments, higher openness to international markets, more international aid and more internal political stabil...

Rationale for study: Vital registration is generally lacking in infrastructurally weak areas where health and development problems are most pressing. Health and demographic surveillance is a response to the lack of a valid information base that can provide high-quality longitudinal data on population dynamics, health, and social change to inform policy and practice. Design and measurement procedures: Continuous demographic monitoring of an entire geographically defined population involves a multi-round, prospective community study, with annual recording of all vital events (births, deaths, migrations). Status observations and special modules add value to particular research areas. A verbal autopsy is conducted on every death to determine its probable cause. A geographic surveillance system supports spatial analyses, and strengthens field management. Population and sample size considerations: Health and demographic surveillance covers the Agincourt sub-district population, sited in rural north-eastern South Africa, of some 70,000 people (nearly a third are Mozambican immigrants) in 21 villages and 11,700 households. Data enumerated are consistent or more detailed when compared with national sources; strategies to improve incomplete data, such as counts of perinatal deaths, have been introduced with positive effect. Basic characteristics: A major health and demographic transition was documented over a 12-year period with marked changes in population structure, escalating mortality, declining fertility, and high levels of temporary migration increasing particularly amongst women. A dual burden of infectious and non-communicable disease exists against a background of dramatically progressing HIV/AIDS. Potential and research questions: Health and demographic surveillance sites — fundamental to the INDEPTH Network — generate research questions and hypotheses from empirical data, highlight health, social and population priorities, provide cost-effective support for diverse study designs, and track population change and the impact of interventions over time.

Aims: This paper examines trends in age-specific mortality in a rural South African population from 1992 to 2003, a decade spanning major sociopolitical change and emergence of the HIV/AIDS pandemic. Changing mortality patterns are discussed within a health-transition framework. Methods: Data on population size, structure, and deaths, obtained from the Agincourt health and demographic surveillance system, were used to calculate person-years at risk and death rates. Life tables were computed by age, sex and calendar year. Mortality rates for the early period 1992—93 and a decade later, 2002— 03, were compared. Results: Findings demonstrate significant increases in mortality for both sexes since the mid-1990s, with a rapid decline in life expectancy of 12 years in females and 14 years in males. The increases are most prominent in children (0—4) and young adult (20—49) age groups, in which increases of two- and fivefold respectively have been observed in the past decade. Sex differences in mortality patterns are evident with increases more marked in females in most adult age groups. Conclusions: Empirical data demonstrate a marked ``counter transition'' with mortality increasing in children and young adults, ``epidemiologic polarization'' with vulnerable subgroups experiencing a higher mortality burden, and a ``protracted transition'' with simultaneous emergence of HIV/AIDS together with increasing non-communicable disease in older adults. The health transition in rural South Africa is unlikely to predict patterns elsewhere; hence the need to examine trends in as many contexts as have the data to support such analyses.

This study analyzes the distribution of sex ratio at birth in African populations using data collected in birth histories in sample demographic surveys (Demographic and Health Surveys and World Fertility Surveys). The average sex ratio from 56 surveys, totaling 1.130 million births, was 1.033 (95% CI, 1.029-1.037), significantly different from the world average of 1.055. The distribution of sex ratios across surveys was found to be heterogeneous, and different from what could have been expected from random fluctuations due to sample size. Three subsets were identified: a subset with lower sex ratios, primarily in countries of eastern and southern Africa of Bantu populations (1.010), a subset with average sex ratios (1.035), and a subset of countries with higher sex ratios, in particular Nigeria and Ethiopia (1.070). Further analysis revealed that African populations are as diverse as other populations, with sex ratios ranging from low values (below 1.00) to high values (above 1.08). Results are discussed in light of independent data sources and in comparison with other human populations.

Using data collected by the Agincourt Health and Population Programme in a rural sub-district of South Africa's Northern Province, this paper describes the residential arrangements of a population in rural South Africa, and analyses the impact of these arrangements on children's educational attainment. Children with co-resident parents generally have higher levels of schooling than those who have one or no co-resident parents. However, having a father who is away from home as a migrant appears to benefit older children whereas, for girls aged 11 to 15, having a mother who is a migrant lowers educational attainment. Children who live in households headed by Mozambican refugees have lower levels of schooling than those who live in non-refugee households. Living in a household headed by a woman is not associated with lower levels of education and, for some age-sex groups, appears to be an advantage.

SummaryThe study investigates the complex relationships between sex-selective abortion and family composition in two countries of the Southern Caucasus: Armenia and Azerbaijan. Data were drawn from maternity histories recorded in Demographic and Health Surveys (DHSs). In both countries, the relationship between the sex ratio of the next birth and the number of girls already born changed from negative to positive after 1992, when sex-selective abortion became prevalent. In Azerbaijan, but not in Armenia, a similar change was noticed for the relationship between the sex ratio of the next birth and the number of boys already born, this time from positive to negative. All changes in slopes were highly statistically significant. These findings indicate that sex-selective abortion was prevalent in both countries, and could work both ways in Azerbaijan. The results are interpreted in terms of ‘gender saturation’, that is a desire of families to better balance the composition of the family when too many children of the same sex are already born, which is consistent with opinion surveys indicating a preference for balanced families.

In October 1994, a retrospective study of mortality of children was conducted in Maringué, a district of central Mozambique. Estimates based on maternity histories of 1503 women aged 15-60 years revealed complex changes in the under-5 death rate. During the colonial period (1955-1974), mortality declined from 373 to 270 per 1000. During the civil war period (1975-1991), mortality increased rapidly to reach a peak of 473 per 1000 in 1986. It declined again thereafter and reached a plateau of 380 in 1991. A health intervention conducted by the International Red Cross Committee since 1992 further reduced mortality to 269 per 1000 in 1994. Most of the 1992-1994 decline was attributable to vaccinations, in particular measles and tetanus immunizations, and to Vitamin A supplementation. (Résumé d'auteur)

Background: Measurement of the level and composition of maternal mortality depends on the definition used, with inconsistencies leading to inflated rates and invalid comparisons across settings. This study investigates the differences in risk of death for women in their reproductive years during and outside the maternal risk period (pregnancy, delivery, puerperium), focusing on specific causes of infectious, non-communicable and external causes of death after separating out direct obstetrical causes. Methods: Data on all deaths of women aged 15-49 years that occurred in the Agincourt sub-district between 1992 and 2010 were obtained from the Agincourt health and socio-demographic surveillance system (HDSS) located in rural South Africa. Causes of death were assessed using a validated verbal autopsy instrument. Analysis included 2170 deaths, of which 137 occurred during the maternal risk period. Findings: Overall, women had significantly lower mortality during the maternal risk period than outside it (age-standardized RR = 0.75; 95% CI = 0.63-0.89). This was true in most age groups with the exception of adolescents aged 15-19 years where the risk of death was higher. Mortality from most causes, other than obstetric causes, was lower during the maternal risk period except for malaria, cardiovascular diseases and violence where there were no differences. Lower mortality was significant for HIV/AIDS (RR = 0.29, P

The 2007 Community Survey conducted in South Africa included questions on maternal deaths in the previous 12 months (pregnancy-related deaths). The Maternal Mortality Ratio (MMR) was estimated at 700 per 100,000 live births, some 30% more than at the 2001 census. This high level occurred despite a low proportion of maternal deaths (4.3%) among deaths of women aged 15–49 years, which was even lower than the proportion of time spent in the maternal risk period (7.6%). The high level of MMR was due to the astonishingly high level of adult mortality, which increased by 46% since 2001. The main reasons for these excessive levels were HIV/AIDS and external causes of death (accidents and violence). Differentials in MMR were very marked, and similar to those found in 2001 with respect to urban residence, race, province, education, income, and wealth. Provincial levels of MMR correlated primarily with HIV/AIDS prevalence. Maternal mortality defined as `pregnancy-related death' appears no longer as a proper indicator of `safe motherhood' in this situation.

The Agincourt health and socio-demographic surveillance system (HDSS), located in rural northeast South Africa close to the Mozambique border, was established in 1992 to support district health systems development led by the post-apartheid ministry of health. The HDSS (90 000 people), based on an annual update of resident status and vital events, now supports multiple investigations into the causes and consequences of complex health, population and social transitions. Observational work includes cohorts focusing on different stages along the life course, evaluation of national policy at population, household and individual levels and examination of household responses to shocks and stresses and the resulting pathways influencing health and well-being. Trials target children and adolescents, including promoting psycho-social well-being, preventing HIV transmission and reducing metabolic disease risk. Efforts to enhance the research platform include using automated measurement techniques to estimate cause of death by verbal autopsy, full 'reconciliation' of in- and out-migrations, follow-up of migrants departing the study area, recording of extra-household social connections and linkage of individual HDSS records with those from sub-district clinics. Fostering effective collaborations (including INDEPTH multi-centre work in adult health and ageing and migration and urbanization), ensuring cross-site compatibility of common variables and optimizing public access to HDSS data are priorities.

The paper presents and discusses the progress in knowledge of African populations and their dynamics over the past 50 years. It takes as a starting point the landmark series of studies published in The Demography of Tropical Africa. Since then major progresses in data collection and data analysis were made, which are reviewed and discussed, with special reference to direct and indirect methods of demographic estimation. A major change occurred about 25 years ago with the development of DHS surveys and the focus on epidemiology and public health issues. Demographic research had to change its paradigms, and major advances were made in our understanding of population dynamics in relation with health issues. In a last part, the paper addresses special topics, unforeseeable events such as the HIV/AIDS epidemics which had major consequences for many demographic processes, and new fields for research around environmental issues. Keywords: Demography; public health; demographic methods; history; sub-Saharan Africa Resume en francais Cette communication presente et discute les progres faits depuis un demi-siecle sur la connaissance des populations africaines et leurs dynamiques. Elle part d’une serie d’etudes pionnieres publiees dans l’ouvrage intitule : The Demography of Tropical Africa. Depuis cette epoque, de nombreux progres ont ete faits en matiere de collecte et d’analyse des donnees, qui sont presentes et discutes, en mettant l’accent sur les methodes directes et indirectes d’estimation demographique. Un changement majeur se produit 25 ans plus tard avec le developpement des enquetes demographiques et sanitaires (EDS), l’interet se portant alors sur les questions epidemiologiques et de sante publique. La recherche demographique a du changer ses paradigmes, permettant de realiser des avancees majeures sur la comprehension des dynamiques de population en relation avec les questions de sante. Dans une derniere partie, la communication traite de sujets speciaux, d’evenements imprevisibles comme l’emergence du VIH/sida, qui a eu d’enormes consequences sur les phenomenes demographiques, et de nouvelles questions comme celles qui ont trait aux questions d’environnement. Mots cle: Demographie; Sante publique; Methodes d’estimation; Histoire; Afrique sub-Saharienne.

International audience; This study compares two methods for testing fertility trends and fertility stalls using Demographic and Health Surveys data. The first method is based on linear regression and uses the equivalence of period and cohort estimates with the same cumulative fertility at age 40, the same number of births, and the same distribution of women by parity. The second method is based on logistic regression. It assumes that the age pattern of fertility is constant over short periods of time. Both methods were applied to fertility trends in several African countries (Ghana, Kenya, Madagascar, Nigeria, Rwanda, Senegal, Tanzania, and Zambia). The two methods were found to predict similar values of cumulative fertility, to produce consistent slopes, to document fertility trends the same way, and to characterize fertility stalls with similar statistical evidence. They can also be used to refute apparent fertility stalls obtained when comparing two point estimates from two successive surveys.

To the Editor—The journal's recent supplement on sex differences in susceptibility and response to infectious diseases was an excellent initiative for promoting research on a neglected topic of major interest [1–8]. If, in general, males show a higher susceptibility to many infectious diseases, the reviews displayed a number of infectious and autoimmune diseases for which females are more vulnerable. Differential vulnerability between males and females may come from exposure, infection (local or systemic), immune reaction, or a combination of these factors. Evidence came mainly from medicine, epidemiology (direct observation), and biology (animal models and in vivo observation). I address another dimension: demographic evidence.

This paper reviews the demographic evidence for the relationship between male circumcision and HIV infection in national or sub-national African populations. A meta-analysis based on 18 countries, representing more than half of the population of sub-Saharan Africa, shows no relationship [standardized odds ratio = 1.00; 95% CI: 0.96–1.05]. There were even more countries in which HIV prevalence was higher among circumcised persons than countries where it was lower. In only five countries, the odds ratio of HIV prevalence (circumcised/intact) was significantly different from 1.0; three countries where it was higher, and two countries where it was lower. The contrast between lack of demographic impact and results from clinical trial is striking, and can probably be explained by the low clinical efficacy in situations of intense and repeated exposure, and by the interactions with the many other determinants of HIV spread. This paper also addresses some ethical and political issues, and in particular raises the question of power abuse, which may lie in the practice of genital mutilations and relevant international recommendations.

SummarySex ratios at birth are known to change during wars or shortly after. This study investigated changes in sex ratios during the civil war that occurred in Tajikistan after the dismantling of the Soviet Union. This civil war was particularly bloody and long lasting, and had many demographic consequences. According to vital registration data, some 27,000 persons died in excess of previous trends during the civil war period (1992–1997), and total mortality was sometimes estimated to be three times higher by independent observers. Birth rates dropped markedly during the war, and sex ratios at birth increased significantly from 104.6 before the war to 106.9 during the war, to return to baseline values afterwards. The change in sex ratio is investigated according to demographic evidence (migration, delayed marriage, spouse separation), substantiated with qualitative evidence (difficulties with food supply), and compared with patterns found in Europe during World War II, as well as with recent wars in the Middle East.

Variations of the sex ratio at birth (SRB) were investigated using maternity history data collected in demographic surveys conducted in sub-Saharan Africa. Thirty-three countries were covered, totaling about 2.0 million births. The average SRB was 1.034 and varied by ethnicity, birth order, and maternal age. The effect of maternal age was significant for younger mothers (12–19 years old) and older mothers (40–49 years old), with a decline in sex ratios with increasing maternal age in both cases. The effect of birth order was significant only for the 20–39-year-old women, with a decline in sex ratio with increasing birth order. These two effects were similar for the three main population groups identified: populations from southern, eastern, and central Africa (SRB = 1.015), populations from West Africa and Sahelian countries (SRB = 1.040), and populations from Nigeria and Ethiopia (SRB = 1.087). In contrast, no effect of marital duration was found.

A comparative study of fertility trends since 1950 in 30 countries from sub-Saharan Africa revealed several cases of “fertility stall”, that is a change from downward fertility trends to flat- or even slightly rising- trends for some time, usually a few years: Ghana (1998-2003), Kenya (1995-2003), Madagascar in urban areas (1987-1993), Nigeria (1999-2003), Rwanda in rural areas (1999-2005), Tanzania in rural areas (1995-2004). In a first part, the paper presents the statistical evidence of changes in fertility trends. In a second part, the analysis focuses on possible causes of these changes. Fertility stalls were often associated with changes in two proximate determinants (contraceptive use and age at marriage) and in two socio-economic correlates (income and labour force participation). The paper concludes to a variety of situations leading to different causality in the various countries, including one case (Ghana) for which no reasonable explanation could be found from the available data.

The study compares the association between using the services of commercial sex workers and male HIV seroprevalence in five African countries: Ghana, Kenya, Lesotho, Malawi and Rwanda. The HIV seroprevalence among men who ‘ever paid for sex’ was compared with controls who ‘never paid for sex’. Results were based on 12,929 eligible men, aged 15–59 years, interviewed in Demographic and Health Surveys. The odds ratio of HIV seroprevalence associated with ever paying for sex was 1.89 (95% confidence interval = 1.57–2.28), with only minor differences by country. The results were stable in multivariate analysis after controlling for available potential cofactors (data on non-sexual routes of transmission were not available). Given the relatively small proportion of men involved, the risk attributable to ‘ever paying for sex’ remained low: 7.1% in univariate analysis and 4.4% after adjustment, and it varied among countries (range 1.3–9.4%). These results match previous observations that commercial sex seems to play a minor role in the spread of HIV in mature epidemics.

Background Maternal mortality remains poorly researched in Africa, and is likely to worsen dramatically as a consequence of HIV/AIDS. Methods The 2001 census of South Africa included a question on deaths in the previous 12 months, and two questions on external causes and maternal mortality, defined as "pregnancy-related deaths". A microdata sample from the census permits researchers to assess levels and differentials in maternal mortality, in a country severely affected by high death rates from HIV/AIDS and from external causes. Results After correcting for several minor biases, our estimate of the Maternal Mortality Ratio (MMR) in 2001 was 542 per 100,000 live births. This level is much higher than previous estimates dating from pre-HIV/AIDS times. This high level occurred despite a relatively low proportion of maternal deaths (6.4%) among deaths of women aged 15–49 years, and was due to the astonishingly high level of adult mortality, some 4.7 times higher than expected from mortality below age 15 or above age 50. The main reasons for these excessive levels were HIV/AIDS and external causes of deaths. Our regional estimates of MMR were found to be consistent with other findings in the Cape Town area, and with the Agincourt DSS. The differentials in MMR were considerable: 1 to 9.2 for population groups (race), 1 to 3.2 for provinces, and 1 to 2.4 for levels of education. Relationship with income and wealth were complex, with highest values for middle income and middle wealth index. The effect of urbanization was small, and reversed in a multivariate analysis. Higher risks in provinces were not necessarily associated with lower income, lower education or higher proportions of home delivery, but correlated primarily with the prevalence of HIV/AIDS. Conclusion Demographic census microdata offer the opportunity to conduct an epidemiologic analysis of maternal mortality. In the case of South Africa, the level of MMR increased dramatically over the past 10 years, most likely because of HIV/AIDS. Indirect causes of maternal deaths appear much more important than direct obstetric causes. The MMR appears no longer to be a reliable measure of the quality of obstetric care or a measure of safe motherhood.

In a rural area of Senegal, 1500 cases of measles and 98 deaths (6.5%) were registered during a 4-year period (1983-1986). For children less than 5 years old, the acute case fatality ratio (CFR) was 9.6%. Compared with index cases who contracted measles in the village, secondary cases infected within the compound had a significantly higher mortality (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.3-6.1). The CFR of secondary cases increased with the closeness of contact with the index cases; the ORs were 1.9 (CI, 0.6-6.0) for children living in the same compound but not the same household, 2.3 (CI, 1.0-5.7) for children living in the same household but not in the same hut, and 3.8 (CI, 1.7-8.4) for children living in the same hut. In large compounds with many cases, the CFR increased exponentially through the succession of generations; the ORs were 2.3 (CI, 1.0-5.2) in the second generation, 3.7 (CI, 1.1-3.0) in the third generation, 5.5 (CI, 1.7-18.1) in the fourth generation, and 16.1 (CI, 5.6-46.3) in the fifth or later generations. Postmeasles mortality through the year following measles infection was also significantly related to the intensity of exposure. Differences in exposure may be a major determinant of child survival, both at time of acute disease and for the long term impact of measles infection.

Aims: To analyse trends in fertility rates and net reproduction rates in Agincourt, a rural area of South Africa located in the former homeland of Gazankulu near the Mozambican border. Trends are analysed in the context of widely available modern contraceptive methods and increasing HIV/AIDS. Methods: A health and demographic surveillance system has been in place since 1992, covering a population of approximately 70,000 persons, with an annual census update and comprehensive recording of births and deaths. It was complemented by a retrospective study of fertility at baseline. Retrospective and prospective data were used to calculate trends in fertility, survival, and net reproduction. When possible, they were compared with data from other censuses and surveys in the same ethnic group. Results: The fertility transition has almost ended over a course of 25 years in Agincourt. The total fertility rate (TFR) averaged 6.0 in 1979 and 2.3 in 2004. Fertility declined in proportionate fashion in all age groups including adolescents in the recent period. The net reproduction rate (NRR) declined from 1.8 to 1.0 during the prospective period (1992—2004). At current rates of change in fertility and mortality, the NRR can be expected to reach 0.63 by the year 2010. Conclusions: The situation of a below-replacement fertility level is new for rural Africa, and is likely to have many demographic, economic and social implications. The population could decline in the country as a whole, and is nearly static in Agincourt because of negative migration flows balancing the small excess from natural increase.

Aim: To identify risk factors for severe childhood malnutrition in a rural South African district with a high HIV/AIDS prevalence. Design: Case-control study. Setting: Bushbuckridge District, Limpopo Province, South Africa. Participants: 100 children with severe malnutrition (marasmus, kwashiorkor, and marasmic kwashiorkor) were compared with 200 better nourished (>-2 SD weight-for-age) controls, matched by age and village of residence. Bivariate and multivariate analyses were conducted on a variety of biological and social risk factors. Results: HIV status was known only for a minority of cases (39%), of whom 87% were HIV positive, while 45% of controls were stunted. In multivariate analysis, risk factors for severe malnutrition included suspicion of HIV in the family (parents or children) (OR 217.7, 95% CI 22.7—2091.3), poor weaning practices (OR 3.0, 95% CI 2.0—4.6), parental death (OR 38.0, 95% CI 3.8—385.3), male sex (OR 2.7, 95% CI 1.2—6.0), and higher birth order (third child or higher) (OR 2.3, 95% CI 1.0—5.1). Protective factors included a diverse food intake (OR 0.53, 95% CI 0.41—0.67) and receipt of a state child support grant (OR 0.44, 95% CI 0.20—0.97). A borderline association existed for family wealth (OR 0.9 per unit, 95% CI 0.83—1.0), father smoking marijuana (OR 3.9, 95% CI 1.1— 14.5), and history of a pulmonary tuberculosis contact (OR 3.2, 95% CI 0.9—11.0). Conclusions: Despite the increasing contribution of HIV to the development of severe malnutrition, traditional risk factors such as poor nutrition, parental disadvantage and illness, poverty, and social inequity remain important contributors to the prevalence of severe malnutrition. Interventions aiming to prevent and reduce severe childhood malnutrition in high HIV prevalence settings need to encompass the various dimensions of the disease: nutritional, economic, and social, and address the prevention and treatment of HIV/AIDS.

A two-sex compartmental model of the dynamics of HIV infection was developed and applied to the case of Zambia. Parameters included age specific rates of fertility mortality entry into sexual life number of partners and age of partners. They were all derived from empirical data from Demographic and Health Surveys and applied by single year of age. The model was unable to fit age and sex patterns of infection observed in 2001. Current knowledge of HIV transmission does not allow fitting the dynamics of HIV epidemics. Further research is needed to understand the dynamics of HIV heterosexual epidemics in Africa. (authors)

This study investigates trends and age-and-sex patterns of mortality in pulmonary tuberculosis (PTB) and PTB/HIV co-infection in a rural population of South Africa. The PTB/HIV mortality emerged in 1994 and has been rising ever since (men: P = 0.001; women: P = 0.020 test for trend). In the last 2 years for both sexes combined 63% (95% CI 51-74%) of PTB deaths were attributable to HIV/AIDS. PTB/HIV death rate was higher in men than in women for all ages combined (RRMH = 2.48 95% CI 1.53-4.04 P less than 0.001). PTB/HIV death rate was also higher in younger individuals (less than 25 years) compared with PTB without HIV/AIDS (P = 0.033) and the median age at death from PTB/HIV in women (28 years) was lower than in men (38 years P = 0.002). While mortality from PTB without HIV remained constant over time HIV/AIDS explained the rise in PTB mortality. In the last 3 years the HIV/AIDS epidemic has caused the number of persons dying of PTB to increase by +117% with the mortality excess being higher in women (+164%) than in men (+103% P = 0.001). Combined PTB and HIV programme activities need to be reinforced to respond to the increase in PTB mortality particularly in women. (authors)

OBJECTIVE: To reconstruct and analyse mortality trends in children younger than 5 years in sub-Saharan Africa between 1950 and 2000. METHODS: We selected 66 Demographic and Health Surveys and World Fertility Surveys from 32 African countries for analysis. Death rates were calculated by yearly periods for each survey. When several surveys were available for the same country, overlapping years were combined. Country-specific time series were analysed to identify periods of monotonic trends, whether declining, steady or increasing. We tested changes in trends using a linear logistic model. FINDINGS: A quarter of the countries studied had monotonic declining mortality trends: i.e. a smooth health transition. Another quarter had long-term declines with some minor rises over short periods of time. Eight countries had periods of major increases in mortality due to political or economic crises, and in seven countries mortality stopped declining for several years. In eight other countries mortality has risen in recent years as a result of paediatric AIDS. Reconstructed levels and trends were compared with other estimates made by international organizations, usually based on indirect methods. CONCLUSION: Overall, major progress in child survival was achieved in sub-Saharan Africa during the second half of the twentieth century. However, transition has occurred more slowly than expected, with an average decline of 1.8% per year. Additionally, transition was chaotic in many countries. The main causes of mortality increase were political instability, serious economic downturns, and emerging diseases.

Premarital fertility, defined as fertility before first marriage, was found to be highly prevalent in Namibia. According to data from the 1992 and 2000 DHS surveys, the proportion of premarital births was 43% for all births, and 60% for the first birth. This seemed to be primarily due to a late mean age at first marriage (26·4 years) and low levels of contraception before first marriage. Data were analysed using a variety of demographic methods, including multiple decrement life table and multivariate logistic models. Major variations were found by ethno-linguistic groups: Herero and Nama/Damara had the highest levels of premarital fertility (above 60%); Ovambo and Lozi had intermediate levels of premarital fertility (around 40%); Kavongo and San appeared to have kept a more traditional behaviour of early marriage and low levels of premarital fertility (around 20%). The largest ethno-linguistic group, the Ovambo, were in a special situation, with fast increasing age at marriage and average level of premarital fertility. Whites and mixed races also differed, with Afrikaans-speaking groups having a behaviour closer to the average, whereas other Europeans had less premarital fertility despite an average age at marriage. Ethnic differences remained stable after controlling for various socioeconomic factors, such as urbanization, level of education, wealth, access to mass media, and religion. Results are discussed in light of the population dynamics and political history of Namibia in the 20th century.

The age pattern of fertility in a rural area of South Africa under health and demographic surveillance (Agincourt subdistrict) was investigated over the 1992–1997 period. The total fertility rate (number of children born, on average, to the women of this population) averaged 3.3 over the period, a major drop from earlier estimates in the same area (6.0 in 1970–1974). Age-specific fertility rates showed an atypical bimodal pattern composed of two components of similar magnitude: premarital fertility (ages 12–26) and marital fertility (ages 15–49). These two components demonstrate a peak of premarital fertility (around age 18–20 years) and a peak of marital fertility (around age 28–30 years). Premarital fertility accounted for 21 per cent of all births, and for 47 per cent of births to women aged 12–26 years. Thus, in the Northern Province of South Africa at least, premarital fertility is a significant demographic and social phenomenon that contributes to a deeper understanding of both teenage and adolescen...

The age pattern of fertility in a rural area of South Africa under demographic surveillance (Agincourt subdistrict) was investigated over the 1992-97 period. The total fertility rate (TFR) averaged 3.3 births per woman of reproductive age over the period, a major drop from earlier estimates in the same area (6.0 births in 1970-74). Age-specific fertility rates showed an atypical bimodal pattern. They were decomposed into two components of similar magnitude: premarital fertility (among women aged 12-26) and marital fertility (among women aged 15-49). The decomposition revealed the two underlying modes: a mode of premarital fertility (among women aged 18-20) and a mode of marital fertility (among women aged 28-30). Premarital fertility accounted for 21 percent of all births and for 47 percent of births among women aged 12-26. This pattern of high premarital fertility appears to reflect a low incidence of contraceptive use before the first birth, especially among adolescents, a low prevalence of abortion, and a high contraceptive prevalence thereafter. This finding calls for a reorientation of the family planning policy, which until now has targeted married women and women who have been pregnant once, but has failed to address the contraceptive needs of young women before their first pregnancy, especially adolescents.

Although the 1918 influenza epidemic was a major demographic event in the US and worldwide it has not been the major focus of studies by demographers. Some of its salient features include the enormity of the number of people who were affected; estimates indicate that one-quarter of the American population had clinically recognizable cases of flu during the epidemic. Also noteworthy is the fact that the 1918 influenza epidemic was associated with exceptionally high mortality both qualitatively and quantitatively. This study presents a relevant finding in the reexamination of published statistics on death: that the 1918 influenza had a strong and fairly long-lasting effect on differential mortality by sex diminishing the earlier female advantage. Specifically it is noted that the mechanism posited is a selection effect whereby those with tuberculosis (TB) in 1918 were more likely than others to die of influenza. This possible outcome affected males more than females because TB morbidity disproportionately affected males. However the reduction of the pool of male TB cases lowered the male TB death rate in the 2 years following 1918 thereby bringing males life expectancy closer to the longer female life expectancy.