This study assessed the rate of primary infertility and its associated factors among 402,807 currently married women aged 20–49 years in India using National Family Health Survey-4 data collected in 2015–2016. Dietary patterns and selected morbidities were included as independent variables, and socioeconomic variables were considered as covariates. Bivariate and multivariate analyses were done to estimate the prevalence of primary infertility and assess its association with the selected variables, respectively. The rate of primary infertility among currently married women in India in 2015–16 was 1.9% and this was significantly associated with younger age (<35 years), higher age at marriage (≥18 years), urban residence, higher secondary or above education and poverty. The consumption of dairy products (OR = 0.79, CI = 0.73–0.86), dark green leafy vegetables (OR = 0.57, CI = 0.39–0.81) and fruit (OR = 0.88, CI = 0.77–1.01) significantly reduced the odds of primary infertility. Daily consumption of fish and aerated drinks was related to 1.06–1.21 times higher odds of primary infertility. Overweight/obesity, high blood pressure and high blood glucose levels were associated with 1.08–1.21 times elevated odds of primary infertility. Thyroid disorder (OR = 1.38, CI = 1.21–1.60), heart disease (OR = 1.17, CI = 1.16–1.19) and severe anaemia (OR = 1.24, CI = 1.00–1.53) were associated with an increased likelihood of primary infertility among women (OR 1.17–1.39, CI 1.00–1.60). The findings provide compelling evidence that primary infertility among women is related to dietary patterns and morbidities. Interventions and programmes targeting the promotion of healthy diets and lifestyles could be beneficial in addressing the issue of primary infertility among women.

After a universal two-child policy was introduced in China in 2016, studies have been published using women’s fertility intentions to forecast future births; however, the recommended algorithms need to be improved. In this study, an algorithm based on the method of limiting factors is developed to retrospectively forecast annual births in Xi’an City in the first three years of policy implementation, i.e. 2016–2018. The 2015 Xi’an Fertility Survey (sample: 560 one-child mothers) showed that 17% of mothers intended to have a second child, 30% were undecided and 53% did not intend to do so at the end of 2015. The low forecast variant based on the updated algorithm indicates that there would be a baby boom in 2016–2018, but the annual births would increase by 13% at most. The forecasting results are basically consistent with the official reports on annual births. This study emphasizes the importance of appropriately adjusting all fertility intentions in birth forecasting, helps to understand women’s fertility behaviour and evaluate the effects of implementing the universal two-child policy, and has important implications for China’s population and family planning work.

The prevalence of overweight in Brazilian adults has grown in recent years. There is evidence indicating that environmental factors, especially social characteristics, may be involved in the aetiology of overweight, but few studies have investigated this association adequately. The main objective of this study was to identify residents’ perception of their social environment (social cohesion, security and violence) and assess its relationship with overweight in a central area of Porto Alegre, Brazil. The associations between socioeconomic characteristics and social environment perception were also explored. This cross-sectional study conducted in 2018–19 had 400 participants aged from 20 to 70 years living in low- and high-income areas of the city of Porto Alegre. Participants’ perception of social cohesion, security and violence were evaluated using a validated questionnaire. Participants’ body mass index (BMI) was measured, and those with a BMI ≥25 kg/m2 were considered to be overweight. Unadjusted and adjusted prevalence ratios (PRs) and 95% confidence intervals (95% CIs) were estimated through Poisson regression analysis; level of significance was 5%. The prevalence of overweight in the sample was 68.8% (95% CI 64.0–73.2). Individuals with a more positive social cohesion perception had a higher prevalence of overweight (PR 1.06; 95% CI: 1.00–1.12; p=0.02) than those with a less positive perception. Brown individuals also had a higher prevalence of overweight (PR: 1.08; 95% CI: 1.02–1.15; p=0.03) than those of other skin colour/race. No association was found between overweight and perception of security or violence. Therefore, social cohesion may be an important factor in overweight and the findings highlight the importance of considering social factors, and their perceptions, when planning actions for the prevention and control of overweight in a population.

Hypertension is one of the primary causes of morbidity and premature mortality among the working-age population in India. This study evaluated the burden of hypertension and unmet need for hypertension care among working-age men aged 15–54 years in India using data from the fourth round of the National Family Health Survey (NFHS-4, 2015–16). An individual was recognized as hypertensive if his blood pressure was over 140/90 mmHg or if he was consuming anti-hypertensive medication to lower his blood pressue. The study design was based on the Rule of Halves framework. Hypertensive cases were segmented into five analytical levels: (1) total, (2) screened, (3) diagnosed, (4) treated and (5) controlled cases. The prevalence of hypertension was 16% (n=16,254) among the men aged 15–54 years. Of the total hypertensive individuals, 63.2% (10,314) were screened, 21.5% (3428) were diagnosed, 12.6% (1862) were treated and only 6.1% (905) had controlled blood pressure. Of the screened individuals, 66.8% (6886) had never been diagnosed, 45.7% (1566) of those diagnosed had not receive treatment and 51.4% (957) of those treated still had uncontrolled blood pressure. The analyses revealed that 36.5% (5940) of hypertensive individuals were lost at the screening stage. The results demonstrate that there is a significant burden of hypertension and unmet need for hypertension care among men aged 15–54 in India. There is an urgent need to develop suitable strategies and programmes to manage this rising burden of hypertension among men, and reduce losses in the hypertension care continuum.

Utilization of antenatal care (ANC) services, as part of reproductive health care, presents a lifesaving chance for health promotion and the early diagnosis and treatment of illnesses throughout pregnancy. This study examines the factors associated with the number and timing of ANC visits among married women in Cameroon using data from the 2018 Cameroon Demographic and Health Survey. The outcome variables were number of ANC visits, categorized as <8 visits or ≥8 visits, and the timing of first ANC visit, categorized as ≤3 months (early) or >3 months (late) (as per the new 2016 WHO recommendations). Descriptive statistics and binary logistic regression were used to analyse the data. Crude odds ratios (cOR) and adjusted odds ratios (aOR) and p-values with significance at <0.05 were used to interpret the results. The proportions of women who had ≥8 ANC visits and first ANC visit at ≤3 months gestation were 6.3% and 35.6% respectively. Women aged 35–39 at childbirth (aOR=3.99, 95% CI=1.30–12.23), middle wealth quintile women (aOR=3.22, 95% CI=1.01–10.27), women whose husbands had secondary (aOR=7.00, 95% CI=2.26–21.71) or higher (aOR=16.93, 95% CI=4.91–58.34) education were more likely to have ≥8 ANC visits. Early timing of first ANC visit was low among women with birth order 3–4 (aOR=0.63, 95% CI=0.46–0.85). Conversely, the likelihood of having early ANC visits was high among women whose pregnancies were intended (aOR=1.32, 95% CI=1.01–1.74), the richest women (aOR=3.89, 95% CI=2.30–6.57) and women whose husbands had secondary (aOR=2.41, 95% CI=1.70–3.64) or higher (aOR=3.12, 95% CI=2.40–7.46) education. The study highlights that age at childbirth, wealth, husband’s educational attainment, birth order and pregnancy intention could influence the utilization of ANC services among married women in Cameroon. Hence, to improve attendance and early initiation of ANC, interventions should be targeted at empowering women financially and removing all financial barriers associated with accessing ANC, improving ANC education among women and encouraging male involvement in ANC education.

Vitamin D is an important nutrient for bone health, and vitamin D deficiency increases the risk of various diseases. Gilgit Baltistan, the northern-most area of Pakistan, has a high prevalence of vitamin D deficiency, despite many nutritional and food safety programmes. The present study aimed to find how knowledge, attitudes and practices associated with vitamin D related to the prevalence of vitamin D deficiency among people residing in different areas of Gilgit Baltistan. The cross-sectional study was descriptive and used data from a survey carried out between February 2019 and December 2020 on individuals of both sexes aged 10 years or over in Gilgit Baltistan. Of the 575 survey participants, 306 (53.2%) had experienced signs and symptoms of vitamin D deficiency, i.e. tiredness, fatigue and bone weakness. Approximately 64.8% had some general knowledge of vitamin D and its relation to health. Participants aged 19–25 years had the highest scores on knowledge of vitamin D. Only 22.7% of interviewees had ever taken any supplements and only 25.6% often exposed themselves to sunlight. Females’ mean knowledge score (28.7; SD 7.02) was higher than that of males (24; SD 9.01). A lack of consistency was observed between attitude towards daylight exposure and knowledge of vitamin D. There was a large correlation between knowledge and attitude (p = 0.001), while a non-significant association was demonstrated between knowledge and practices (p = 0.1). Better knowledge, attitude and practices by people living in cities or more-developed regions indicates that education can be an effective way to provide awareness regarding micronutrient deficiencies. More emphasis is needed on enhancing knowledge, awareness and practices associated with vitamin D deficiency in rural areas of Pakistan. It is strongly recommended that an awareness campaign on micronutrients is launched in both rural and urban areas of Pakistan, concentrating on poor socioeconomic settings.

Around 40% of pregnancies worldwide are unintended and a half of those are terminated. Yet, few international comparisons of unintended pregnancy resolution (choosing birth or abortion) exist. This study analysed how parous women’s pregnancy intentions and abortion decisions are associated with their reproductive histories and country contexts using twelve Demographic and Health Surveys representing four context groups: post-Soviet/communist and Asian countries with liberal abortion legislation, and Asian and Latin American countries with restrictive abortion legislation. Similarities were found across contexts: preference to have children of both sexes, space births, stop childbearing after reaching desired family size and an increased likelihood of unintended pregnancy when using less-effective contraceptive methods versus none. Contextual factors most clearly associated with reports of unintended pregnancy resolution were type of abortion legislation and living in post-Soviet/communist contexts. Women’s propensity to report abortions and unintended pregnancy varied by context and the decision-making processes for pregnancy versus fertility management were different.

Digit ratio – a putative measure of prenatal sex steroids – may be related to body mass index (BMI). However, reports of correlations between 2D:4D and BMI have yielded mixed results with some studies showing no relationship while others have reported positive associations in men or women only. This study considers associations between self-reported 2D:4D and BMI in a large online survey (i.e. the BBC Internet Study). At the individual level, there was a weak positive association between 2D:4D and BMI in both sexes with greater effect sizes in women. Body mass index was positively related to age and negatively related to parental income; however, the relationship between 2D:4D and BMI was independent of both variables. At the national level, mean 2D:4D per country showed positive associations with mean national BMI but those correlations were restricted to females. It is concluded that BMI is positively related to low prenatal testosterone and high prenatal oestrogen. Parental income inequality may influence both prenatal sex steroids (through a ‘Trivers–Willard’ effect) and BMI such that increases in inequality result in reductions in prenatal testosterone and increases in BMI at the individual and national level.

In the light of changes in the living conditions of populations, excess adiposity is currently a serious public health problem worldwide. The aim of this study was to assess the changes in the body fat ratio among preschool children aged 3–7 years from Kraków, Poland, between 2008 and 2018. The study group consisted of children examined in two cross-sectional studies. Analysed characteristics included triceps, calf, subscapular, abdominal and suprailiac skinfold thicknesses, and adiposity calculated according to Slaughter’s equations. The trunk adiposity index and limbs-to-trunk fat ratio were also calculated. Statistical significance was obtained using two-way ANOVA and Tukey’s tests. Lower-limb adiposity was largest in the 2008 cohort and trunk adiposity was greater in the 2018 cohort. The mean values of the trunk adiposity index and limbs-to-trunk fat ratio were lower in the 2018 cohort than in the 2008 cohort. The 2018 cohort was also characterized by a lower overall adiposity. Regardless of the lower body adiposity percentage, in 2018 there was a tendency towards the central allocation of fat tissue. This is a negative phenomenon because, especially when co-existing with reduced lower-limb adiposity, it is associated with an increased risk of metabolic and cardiovascular diseases, even in young children.

In October 2015, the Chinese Government announced that the one-child policy had finally been replaced by a universal two-child policy. China’s universal two-child policy is highly significant because, for the first time in 36 years, no one in an urban city is restricted to having just one child. This cross-sectional study was conducted to explore future fertility intentions and factors influencing individual reproductive behaviour (whether to have two children) in Dalian City. A total of 1370 respondents were interviewed. The respondents’ mean ideal number of children was only 1.73, and urban respondents’ sex preference was symmetrical. A total of 19.0% of the respondents were unmarried, 64.5% were married and had childbearing experience and only 6.3% of married respondents had two children. Among the 1370 participants, 30.4% stated that they would have a second child, while 69.6% refused to have a second child in the future. Binary logistic regression analysis (Model 1) showed that the following characteristics were associated with having only one child in the future: being female, being older, having a lower education level, being born in Dalian, having a lower family income and reporting one child as the ideal number of children. Model 2 (comprising only respondents with childbearing experience) showed that respondents who were female, had a lower family income and were unable to obtain additional financial support from parents were more likely to intend to stick at one child. In addition, respondents’ ideal number of children and childbearing experiences had a significant influence on future fertility intentions. These results suggest that fertility intentions and reproductive behaviours are still below those needed for replacement level fertility in Dalian City. China’s policymakers should pay more attention to these factors (socioeconomic characteristics, economic factors, desired number of children and childbearing experiences) and try to increase individual reproductive behaviour.

Age misreporting is a common phenomenon in Demographic and Health Surveys, and there are numerous reasons for this. The trend and pattern of disparity in age heaping vary between countries. The present study assesses age heaping in the selected South Asian countries of Afghanistan, India, Nepal, Bangladesh and Pakistan using data from the most recent round of the Demographic and Health Survey. The respondent sample sizes were 203,703 for Afghanistan, 2,869,043 for India, 49,064 for Nepal, 81,618 for Bangladesh and 100,868 for Pakistan. Age heaping was assessed by respondent’s age, education level, sex and level of education. Whipple’s index was calculated to assess systematic heaping on certain ages as a result of digit preference. Bangladesh, Afghanistan and India showed stronger preference for ages ending with the digits ‘0’ and ‘5’ compared with Pakistan and Nepal among uneducated respondents. On the other hand, strong avoidance of ages ending in the digits ‘1’, ‘4’ and ‘9’ was observed in Bangladesh, Afghanistan and India. However, urban–rural place of residence was not found to be associated with digit preference in the study countries. Among males, age misreporting with the final digits ‘0’ and ‘5’ was highest in Bangladesh, followed by Afghanistan and India, and Nepal showed the least displacement. Strong digit preference and avoidance, and upper age displacement, were witnessed in the surveys conducted in Bangladesh, Afghanistan and India on the parameters of sex and education level. Innovative methods of data collection with the measurement and minimization of errors using statistical techniques should be used to ensure accuracy of age data.

Empirical data on the relations between mating and reproductive success are rare for humans, especially for industrial and post-industrial populations. Existing data show that mating (and especially long-term mating) can be beneficial for fitness, especially that of males. This finding is in line with the hypothesis of sexual selection operating in human populations. The present research expands on previous studies by: 1) analysing additional fitness indicators, including having children with different partners; 2) including parental investment in the analysis as another important marker of sexual selection; 3) analysing several mediators between mating, reproductive fitness and parental investment, i.e. age of first and last reproduction and desired number of children. The data were obtained in 2019 from a sample of parents living in Serbia (N=497). The findings showed that long-term mating (duration of longest partner relationship) was positively related to parental investment and number of offspring and grand-offspring. Furthermore, the link between long-term mating and reproductive success was completely mediated by the age of first reproduction and desired number of children. Short-term mating (number of sexual partners) was marginally positively related to the number of children participants had with different partners and negatively related to parental investment. No sex differences in the link between mating, fitness and parental investment were detected. In general, the signatures of sexual selection were weak in the present data, but those that were detected were in line with sexual selection theory. The present findings provide a deeper insight into the adaptive function of mating and also the mechanism of how mating is beneficial for fitness.

The aim of this paper was to evaluate the socioeconomic differences in adult anthropometric parameters of young women in Poland. The study was cross-sectional and conducted in the years 2015 to 2018 among 1257 women aged 19–24 years. The heights, weights, wrist widths and waist, hip and chest circumferences of the subjects were measured. Body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), waist-to-chest ratio (WCR) and chest-to-height ratio (CHtR) were calculated. A survey was conducted to collect data on the women’s socioeconomic characteristics. The application of the Generalized Linear Model (GLM) including all socioeconomic indicators (urbanization level of place of residence in childhood, parental education, number of siblings, material conditions) revealed no significant association of these with any of the analysed anthropometric traits. The results of the logistic regression showed no significant differences in the risk of underweight, too low abdominal adiposity or too high abdominal adiposity. However, the risk of overweight and obesity was significantly affected by the degree of urbanization of the women’s place of residence in childhood and by their number of siblings. The results show that the socioeconomic factors that once had a significant influence on anthropometric traits currently do not play such an important role. This change can be explained by the equalization of living conditions and lifestyles of individual social groups in Poland.