Urinary oestrogen and pregnanediol values were measured in 24 boys and 38 girls between the ages of 2 and 13 years. Longitudinal studies were conducted on eight girls, two of whom collected for periods of 4 and 5 years which included menarche and in one case establishment of ovulation. Highly sensitive assay methods were developed for measuring the very small amounts of oestrone, oestradiol and oestriol and pregnanediol present in the urine of young children. The total oestrogen values were within the submicrogram range of 0·1–0·5 μg/24 hr in the children aged 2–8 years, with no differences seen between the boys and girls. After the age of 8 years, oestrogen values above 1 μg/24 hr began to be encountered and by age 11½ years the majority of subjects were recording oestrogen values above this figure. The rise in the oestrogen values was more rapid in the girls than in the boys. Evidence was presented that a value of approximately 1 μg/24 hr represents the minimum oestrogen production for the initiation of breast development. The oestrogen values were fluctuating with irregular periodicities at all ages and the gradual general rises seen after the age of 8 years could be arrested at any stage for a year or more. Menarche was preceded by marked periodic fluctuations in oestrogen output which peaked above 15 μg/24 hr. In all subjects studied, the initial bleeding cycles were anovulatory as judged by the low pregnanediol values, the usual pattern being one of fluctuating oestrogen production. One subject was studied fully through to the establishment of ovulation, which first occurred 12 months after menarche. The approach of ovulation was indicated by pre-menstrual rises in pregnanediol which increased in amplitude from 0·4 mg/24 hr until finally 2 mg/24 hr was exceeded (the value accepted for ovulation). Evidence was presented that the interval from menarche to ovulation in different individuals was very variable, extending from ovulation at menarche itself to periods of more than a year. Recording of self-observed symptoms of production of cervical mucus could be of considerable value in documenting these events in larger populations.

Despite the increasing interest in the determinants of adolescent undernutrition in low- and middle-income countries, a comprehensive multi-level overview at the country level is missing. Using the nationally representative 2014 Nepal Adolescent Nutrition Survey, this study aimed to provide a comprehensive overview of the sociocultural and economic determinants of stunting and thinness of adolescent boys and girls in Nepal. Multivariate logistic regression models were used to estimate the associations between multiple individual, household and community determinants and stunting and thinness among 3773 adolescents aged 10–19 years (1888 boys and 1885 girls). The prevalence rates of stunting and thinness indicated suboptimal nutritional status and an inadequate growth environment in Nepali adolescents. The results highlighted an association of paternal occupation and education, household income, number of earning household members, geographical place of residence, caste/ethnicity and nutritional knowledge with stunting, with higher odds for males and older adolescents. Paternal occupation, education, household income, geographical region, caste/ethnicity and nutrition knowledge were associated with thinness, with higher odds for males and younger adolescents. The findings underscore the importance of involving adolescents, their parents and their communities in interventions. Such interventions should not only be aimed at improving adolescent nutrition but also at optimizing adolescents’ growth environment for better health and development. Future research should focus on context-specific causal pathways and mechanisms through which sociocultural and economic determinants influence nutritional outcomes within broader societal, cultural and political settings. A longitudinal approach, including a range of dietary and nutrition indicators would allow understanding how and when the relative importance of these factors change during adolescence.

Two samples of births were used to examine the effect of son preference and population policy on sex ratios in Hebei and Shaanxi provinces of China. The results from all births to women aged 15–49 in the 1985 In-Depth Fertility Survey indicated a strong son preference but no clear policy impact on sex ratios at different birth orders. In a sample of selected births during 1975–84 to women aged 40 or under, the mixed influences of son preference and population policy were clearly reflected in the high and rising overall ratios at birth, and the increasing sex ratios with parity. Possible explanations for these findings are discussed.

Consanguinity is studied in a large sample of marriages among Dhangars of Maharashtra, India. The 22 endogamous castes included in the study show great variation in incidence, about an overall frequency of 26.4%. Matrilateral first cross-cousin unions are more frequency than patrilateral, and maternal uncle-niece nuions least frequent. Geograbhical differences are conspicuous, and all three types of consanguineous union show characteristic patterns; matrilateral unions increase in frequncy northwards, patrilateral and uncle-niece decrease northwards. The inbreeding levels among the Dhangars are high compared to other Maharashtrian groups, but substantially lower than in southern Dravidian speaking groups.

Eight hundred and eighty-seven students from two major universities in Delhi, India, were surveyed, using a self-administered questionnaire, about their sexual knowledge, attitudes and behaviour. The data show that female students seem to be rejecting traditional Indian repressive sexual standards of premarital and non-procreative sex and the gender differences are beginning to narrow. Despite their sexual awareness, the students were highly ignorant of the facts of life. Being male and married did not make them more knowledgeable.

In India, non-communicable diseases (NCDs) accounted for nearly 62% of all deaths in 2016. Four NCDs – high blood pressure, diabetes, asthma and heart disease – together accounted for over 34% of these deaths. Using data from two rounds of the India Human Development Surveys (IHDSs), levels and changes in the prevalence rates of the four NCDs (based on diagnosed cases) among adults aged 15–69 years in India between 2004–05 and 2011–12 were examined by socioeconomic and demographic factors and for five broad occupation categories. The socioeconomic and demographic risk factors for each of these NCDs were determined using multiple linear logistic regression analysis of pooled data from two rounds of the IHDS. The results showed that while urban residence, age, female sex and education were associated with higher odds of high blood pressure, diabetes and heart disease, household economic status was associated with higher odds for all four NCDs. Furthermore, increased higher odds of high blood pressure, diabetes and heart disease were found for the legislator/senior official/professional occupation group compared with non-workers. Skilled agricultural/elementary workers had lower odds of high blood pressure, diabetes, asthma and heart disease. Craft/machine-related trade workers had higher odds of high blood pressure and diabetes, and reduced odds of asthma and heart disease. Compared with non-workers, the odds ratios for asthma were lower for all other occupational categories. During the two study decades, the Government of India implemented several programmes designed to improve the health and well-being of its people. However, more focused attention on the adult population is needed, and special attention should be paid to the issue of the occupational health of the working population through the strict implementation of work place safety protocols and the removal of potential health hazards.

This study investigated gender difference in the effects of social support, including emotional support and instrumental support (such as help when sick and financial assistance), and social activities on perceived health of middle-aged and older adults in South Korea. Data were acquired from 3771 men and 4954 women aged 40 years and older who participated in the 2005 cross-sectional survey of the Seoul Citizens Health and Social Indicators Survey. Using multiple regression analysis, both age- and gender-specific differences related to social support and engagement in social activities and self-rated poor health were examined. Poor emotional support from close friends, relatives or someone with whom one could talk about worries was strongly associated with poor self-rated health in men, with the greatest effect in older men. Lack of engagement in social activities was associated with self-rated poor health in older adults, especially in older men. Poor instrumental support was associated with perceived poor health only in middle-aged women. As a health improvement strategy for men aged 65 years and older especially, emotional support should be considered. Measures should be considered for encouraging social activities by older adults, particularly older men.

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.

Differentials in child survival in Bangladesh have been examined using a number of socioeconomic and environmental factors on data from the 1989 Bangladesh Fertility Survey. Multivariate analysis reveals that both wife's and husband's education and household electricity show a significant positive association with child survival. The respondent's working status exerts a significant negative influence. Wife's education has a greater influence on child survival in Bangladesh than that of husband's education.

Medical records from maternity clinics in three Norwegian cities, Oslo, Bergen and Trondheim, have been used to study the relationship between lactation and post-partum amenorrhoea during the period 1860–1964. Resumption of menses after a period of post-partum amenorrhoea has been examined separately during lactation, after cessation of lactation, and in the absence of lactation, in 5250 cases. During ongoing lactation the median duration of post-partum amenorrhoea was found by survival analysis to be 12 months for women who had given birth before 1900 and 6 months for women who had given birth after 1900. In a Cox regression analysis, age of menarche and parity were found to influence the duration of post-partum amenorrhoea, in addition to the child's birth year. With a later age of menarche there was longer amenorrhoea, and primiparae resumed menses earlier than multiparae. After cessation of breast-feeding the median duration of amenorrhoea was 1 month, the only variable significantly influencing it being the age of menarche, a younger age showing a shorter duration. In the absence of lactation the survivor function started to decline after 3–4 weeks, and had a half-life of 2 months.

None of the variables indicating the woman's social condition seemed to influence the duration of amenorrhoea. The decline in the duration of post-partum amenorrhoea during ongoing lactation from 1860 until today is therefore probably caused by a changed breast-feeding pattern rather than by improved nutrition for women giving birth.

I read with great interest Akrami and Osati’s article entitled ‘Is consanguineous marriage religiously encouraged? Islamic and Iranian considerations’ published in the March 2007 issue of the Journal of Biosocial Science (Akrami & Osati, 2007). The authors showed that in many Islamic sources, there is no sign that could be described as encouraging cousin marriages. I would like to make a few comments about it.

This study was carried out to quantify secular trends in seasonal variation in births in Malta, a small Mediterranean country where the vast proportion of births occur in wedlock due to a predominantly Roman Catholic population. It also related such variations to seasonal variation in marriages. Annual seasonal peaks of marriages and births were analysed over the period 1950–1996 by X11 ARIMA. A significant peak in marriages (n=111,932) in the third quarter of the year was found for almost the entire period under study. This was paralleled by a peak in births (n=299,558) for the period 1970–1996, which lagged after the peak in marriages by 13–14 months. For the period 1994–1996, when monthly data for monthly pregnancies were available by pregnancy order, the peak in births was caused by first pregnancies only. Seasonal patterns in births occur almost universally due to cultural and/or biometeorological factors. The best known patterns include those of the southern United States, where births decline in April and May, and in northern Europe, where births peak in March and April. In Malta, the late summer peak in births appears to be due to a practical and planned approach by Maltese couples to contraceptive planning, probably influenced by the Roman Catholic ethos and social pressures, with unprotected intercourse occurring only after marriage. In Malta, birth control, albeit by so-called natural methods, was introduced in the 1960s. Prior to this period, births peaked towards the beginning/end of the year, and this may be the more natural seasonality of births in Malta.

In this study it is hypothesized that taller individuals are more likely to move up the scale of educational attainment compared with shorter individuals from the same social background. Three national cohorts of 19-year-old males were considered: 29,464 born in 1967 and surveyed in 1986, 31,062 born in 1976 and surveyed in 1995, and 30,851 born in 1982 and surveyed in 2001. Four social variables were used to describe the social background of each conscript in the three surveys: degree of urbanization, family size, and parental and maternal educational status. The educational status of each conscript was classified into two groups: (1) those who were secondary school students or graduates, or who had entered college, and (2) those who had completed their education at the primary school level or who had gone to a basic trade school. Multiple binomial logistic regressions were used to estimate the relative risk of achieving higher educational status by 19-year-old males relative to height and the four social factors. Consistently across the three cohorts the odd ratios (ORs) indicate that height exerts an independent and significant effect on the attained level of education at the age of 19 years in males (1986: OR=1·24, p<0·001; 1995: OR=1·24, p<0·001; 2001: OR=1·20, p<0·001). Two possible, not mutually exclusive, selective mechanisms are postulated and discussed: ‘passive’ and ‘active’ action.

The origin of talent and expertise is currently the subject of intense debate, with explanations ranging from purely biological to purely environmental. This report shows that the population of expert chess players in the northern hemisphere shows a seasonal pattern, with an excess of births in late winter and early spring. This effect remains when taking into account the distribution of births in the population at large, using statistics from the European Union member countries. A similar pattern has been found with schizophrenia, and the possible link between these two phenomena is discussed.

The effects of socioeconomic and geographical factors on age-specific mortality by suicide in men were assessed in 46 Japanese prefectures (counties) by stepwise regression analysis twice at 5-year intervals, before and after a serious economic crisis. The following factors were significantly related to the mortality in the two years: (1) the proportion of old and young men in the population for young men; (2) low income for middle-aged men; and (3) rural residence for elderly men. The mortality significantly increased after the crisis in young and middle-aged men, while no significant alteration was observed in elderly men. It is suggested that young and middle-aged men are more sensitive to socioeconomic changes in society while elderly men are mainly affected by the factor of rural residence.

That married people have lower death rates than either the unmarried or the widowed has been recognized since the mid-19th century. Marital condition involves diverse and complex selection processes and is associated with differences in life style, factors which may contribute to differences in mortality. Mortality statistics of married people are presented here by age of surviving partner in an attempt to assess the influence of age difference between spouses.

This study estimates the effect of dysgenic trends in Taiwan by exploring the relationships among intelligence, education and fertility. Based on a representative adult sample, education and intelligence were negatively correlated with the number of children born. These correlations were stronger for females. The decline of genotypic intelligence was estimated as 0.82 to 1.33 IQ points per generation for the Taiwanese population.

A geographically stratified cross-sectional survey was conducted in 2002 to investigate household-level factors associated with use of mosquito control measures and self-reported malaria in Malindi, Kenya. A total of 629 households were surveyed. Logistic regressions were used to analyse the data. Half of all households (51%) reported all occupants using an insecticide-treated bed net and at least one additional mosquito control measure such as insecticides or removal of standing water. Forty-nine per cent reported a history of malaria in the household. Of the thirteen household factors analysed, low (OR=0·23, CI 0·11, 0·48) and medium (OR=0·50, CI 0·29, 0·86) education, mud–wood–coral (OR=0·0·39, CI 0·24, 0·66) and mud block–plaster (OR=0·47, CI 0·25, 0·87) wall types, farming (OR=1·38, CI 1·01, 1·90) and travel to rural areas (OR=0·48, CI 0·26, 0·91) were significantly associated with the use of mosquito control, while controlling for other covariates in the model. History of reported malaria was not associated with the use of mosquito control (OR=1·22, CI 0·79, 1·88). Of the thirteen covariates analysed in the second model, only two household factors were associated with history of malaria: being located in the well-drained stratum (OR=0·49, CI 0·26, 0·96) and being bitten while in the house (OR=1·22, CI 0·19, 0·49). These results suggest that high socioeconomic status is associated with increased household-level mosquito control use, although household-level control may not be enough, as many people are exposed to biting mosquitoes while away from the house and in areas that are more likely to harbour mosquitoes.

In 1996, the Ministry of Health in Ghana included emergency contraception (EC) in its newly issued National Reproductive Health Service Policy and Standards. A short survey was conducted in the summer of 1997 to evaluate health providers' knowledge of EC. Of the 325 providers interviewed, about one-third (34%) had heard of EC. No provider had sufficient knowledge to prescribe EC correctly. A well-coordinated training programme for providers will have to precede successful introduction of EC in Ghana. Moreover, a dedicated product may be critical for the successful introduction of EC in a country like Ghana, where provider knowledge is low.

The study examines the impact of body build on differential fertility patterns in 93 !Kung San and 85 Kavango females from northern Namibia. In both groups shorter females had more offspring, but also more dead offspring, than taller females. The interaction between body weight and fertility was different in both groups and may be due to different nursing behaviour. There was a positive relationship between the typical pedomorphy and fertility in the! Kung San, and directional selection processes may be important.