Reproduction in India is mainly confined to within marriage. The fertility preferences of spouses will not necessarily be the same, but discussion between couples creates scope for understanding between spouses after marriage. Knowing each other’s opinions facilitates decision-making on sensitive matters such as contraception use and desired family size. This study used data from the India Human Development Survey-II (2011–12), and was based on a sample of 31,276 currently married women. The aim was to understand the role of pre-marital communication, studied through the choosing of husbands, mutual communication before marriage and duration of time spouses knew each other before marriage on the fertility preferences of couples post-marriage. These preferences included contraception use, who has most say on the number of children and the gap between desired and actual number of offspring. The results showed that wives who knew their husbands or who had any kind of communication with them before marriage had a greater chance of being involved in fertility decisions. However, most fertility decisions were found to be male-driven. Wives who knew their husbands for more than a month before marriage took more decisions on number of children (27%) than those who only knew their husbands from the day of their wedding (20%). Wives were less likely to have more children/sons/daughters than desired if they had some communication with their husbands before marriage. A better understanding of fertility preferences between spouses might help to curb unwanted births through delaying or limiting births by contraception use. Families in India could encourage couples to interact before marriage so they can make collective decisions on contraception use and/or the number of children they have.

Several studies have indicated that consanguineous marriages (unions between biologically related persons) are associated with increased risk of autosomal recessive diseases and several multifactorial traits. Mandaeans are a closed ethno-religious community living in areas of southern Iraq and Iran (Khuzestan Province). There are currently no data on the prevalence of consanguineous marriages among Mandaeans. The present study was carried out in 2016 to determine the prevalence of consanguinity among Iranian Mandaeans living in Khuzestan Province, south-west Iran. A total of 137 couples (urban areas: 79 couples; rural areas: 58 couples) were included in the study. Information on the consanguineous marriages of the subjects was collected through direct interviews. Marriages were classified by the degree of relationship between couples as double first cousins, first cousins, first cousin once removed, second cousins and unrelated marriages. The coefficient of inbreeding (F) was calculated for each couple and the mean coefficient of inbreeding (α) estimated for the population, stratified by rural and urban areas. The overall frequency of consanguinity was found to be 50.7% in urban and 86.2% in rural areas. There was a significant difference between rural and urban areas in types of marriages (χ2=24.8, df=4, p<0.001) and first cousin marriages (51.8%) were the most common type. The overall α-value was estimated to be 0.0363 for the Iranian Mandaean population.

The enduring sub-replacement level of fertility in Iran is the result of changing timing of births. Using data from the 2015 Hamedan Survey of Fertility, conducted in a representative sample of 3000 married women aged 15–49, this study examined variations in median lengths of birth intervals employing cumulative survival functions, and investigated the determinants of birth interval lengths using regression hazard models. The results showed that the median first, second and third birth intervals, estimated at 28, 74 and 136 months respectively, doubled between 1995 and 2015. The multivariate analysis results indicated the strong impact of contraceptive use and higher education on lengthening birth intervals, with greater effects on the timing of second and third births. The relative risks of second and third births were higher among rural migrants, unemployed women and those with shorter periods of breast-feeding and the death of a preceding birth. Only timing of the third birth was influenced by son preference. The implications of the results for low fertility and maternal and child health in Iran are discussed.

The inability to have children affects couples worldwide and causes emotional and psychological distress in both men and women. Turkey is a country that lays particular emphasis on the issue of infertility, especially after experiencing a dramatic fertility decline over the last two decades. This study aimed to understand the changes in the prevalence of infertility in Turkey using three different approaches: the DHS Approach, the Constructed Approach and the Current Duration Approach. Furthermore, the factors contributing to elevated risks of infertility as derived from the Constructed Approach were investigated using four different logistic regression models. The data came from the 1993, 1998, 2003, 2008 and 2013 Demographic and Health Surveys conducted by the Hacettepe University Institute of Population Studies. The findings of the Constructed and Current Duration Approaches suggested that the prevalence of infertility decreased markedly from 1993 to 2013 in Turkey. This decline was the result of improvements in maternal health care services in Turkey, as well as an increase in the use of Assisted Reproductive Technology (ART), from 1.9% in 2008 to 4.1% in 2013. The results of the final logistic regression model suggested that the risk of infertility was significantly higher among women aged between 35 and 49 (p<0.01), uneducated women (p<0.01), women whose age at first marriage was over 30 (p<0.01), women defined as overweight (p<0.05) and women whose age at menarche was less than 12 years (p<0.05). This is the first nationwide study to examine the prevalence of infertility and its socio-demographic risk factors in Turkey, a developing country; previous studies have established these risk factors mainly in developed countries.

Societal gender inequality and a preference for male children has been shown to be detrimental to girls’ health. This is despite females’ innate biological advantage early in life. The negative effects of gender inequity on female health are most pronounced in resource-poor countries, where cultural norms supporting a preference for male children are strongest. However, most of what is known about gender inequality and child health comes from studies of singleton births. There is little evidence for how, or if, the disadvantages associated with gender bias and son preference extend to multiple births, a population inherently at risk for a number of health challenges. This analysis examines whether gender bias in health outcomes exists for twins. Data on live twin births from 38 Demographic and Health Surveys were compiled (n=11,528 individuals) and twins were categorized as girl/girl, girl/boy, boy/girl or girl/girl. Gender inequality was measured via the Gender Inequality Index. Multilevel logistic regression models examined associations between twin sex composition, gender inequality and eight outcomes of infant and child morbidity, mortality and mother’s treatment-seeking behaviours. Twin pairs containing girls had significantly lower odds of first-year mortality. Higher country-level gender inequality was associated with higher odds of reporting diarrhoea and fever/cough, as well as an increased odds of post-neonatal mortality. Results suggest that the biological advantage for females may be stronger than son preference and gender inequality in the first year of life. Understanding these relationships has the potential to inform efforts to curb the influence of gender preference on the health of female children in resource-poor settings.

Tubal ligation is the modal form of family planning among American women aged 30 and older. As the preference for tubal ligation over cheaper, lower risk and more reliable methods, such as vasectomy, has puzzled experts, a theoretical approach that explains this preference would be useful. The present study investigates the high prevalence of voluntary sterilization among American women from the perspective of life history theory, arguing that the trade-offs between investing in current and future offspring will favour tubal ligation when women cannot obtain reliable male commitment to future parental investment. Data came from the National Survey of Fertility Barriers (NSFB), a nationally representative survey of 4712 American women aged 25–45 conducted between 2004 and 2007. Four novel predictions of the prevalence of tubal ligation, drawn from life history theory, were developed and tested: 1) it is most common among unpartnered women with children, and least common among married women with children; 2) it is negatively correlated with age at first birth; 3) it is least common among highly educated women without children, and most common among less educated women with children; and 4) among women with two or more children, it is positively correlated with lifetime number of long-term partners. These predictions were tested using multivariate regression analysis. The first prediction was not supported: women with children were more likely to be sterilized, regardless of their marital status. The other three predictions were all supported by the data. The results suggest that trade-offs influence women’s decisions to undergo voluntary sterilization. Women are most likely to opt for tubal ligation when the costs of an additional child will impinge on their ability to invest in existing offspring, especially in the context of reduced male commitment.

Males and females differ in their preference for occupations and sporting activities, and differ also in risk-taking attitudes. In addition to other explanations, prenatal hormone exposure has been implicated in these gender-associated differences. The ratio of the relative lengths of the second-to-fourth digits (2D:4D) is a proxy indicator of prenatal exposure to testosterone relative to oestrogen. The 2D:4D ratio has been found to be associated with choice of occupation, particularly among females. This study investigated whether 2D:4D differed between police officers and a control group of civilians in Wrocław, Poland. Participants were 147 male and 55 female police officers and 91 male and 75 female civilian controls. The police officers had to undergo rigorous physical ability tests during recruitment and their job bore relatively higher risk, whereas the controls had a normal civilian lifestyle. Height, weight, hand grip strength and lengths of the second and fourth digits were measured. Analyses of variance and covariance were employed to assess the significance of difference in digit ratio between groups (police officers and civilians) allowing for interaction with sex. The policewomen, compared with the female controls, were taller and had stronger hand grip strength, but had lower 2D:4D in the right hand and average 2D:4D of both hands. However, male and female police officers slightly differed only in the right hand digit ratio but not in the left hand ratio or the average for the two hands. However, the control group showed significant sex differences in all digit ratios with higher (feminine) mean values in females. The study provides further evidence that prenatal testosterone exposure, as reflected in the 2D:4D ratio, might have an association with choice of occupation, particularly among females.

In the last 50 years Thailand has achieved advanced demographic and health transitions. Many infectious diseases are controlled and infant and maternal mortality rates are among the lowest in the region. Within such a low mortality setting, however, substantial variations in health persist, with education being a major driver. This paper assesses the ongoing mortality transition in Thailand, examining relationships between risk factors and mortality outcomes among a large nationwide cohort of distance-learning Open University students, as well as examining the differential mortality benefit enjoyed by this educated group when compared with the general Thai population. The cohort comprised 87,151 participants, who in 2005 completed a questionnaire collecting detailed information on socio-demographics, health behaviours and health outcomes. Participants were aged 15–87 at baseline and lived in all regions of the country. Cohort members’ citizen identification numbers were matched with official death registration records to identify mortality among participants. A total of 1401 deaths were identified up to November 2016. Results show cohort study participants experiencing mortality at approximately one-third of the rate of the general population in the same age and sex groups. The gap between the mortality rates in the two groups widened with increased age. Differential risk factor prevalence among the two populations, particularly lower overweight and obesity prevalence and lower cigarette smoking rates in the cohort, can explain some of this variation. The largely unmeasurable effect of aspiration for life improvement through distance education while embedded in their communities is shown by this study to have a powerful effect on mortality risk. With overall education levels, including higher education, rising in Thailand this growing group of educated aspirational Thais may represent future trends in Thai mortality. Identifying the drivers and characteristics of this mortality variation can help inform policies to provide health services and to help reduce mortality in the whole population.

Targeting reductions in fertility remains a key development goal, as too-high fertility hampers the economic and health prosperity of low- and middle-income countries. However, critical to the success of gaining reductions in fertility is the ability to understand the factors that are shaping fertility, and to understand the factors that are acting to keep fertility levels high. To contribute to this understanding, this study applied the Bongaarts (2015) adjusted proximate determinants of fertility model to 33 low- and middle-income countries using data collected from the Demographic and Health Survey (DHS) programme between 2000 and 2016. Results from the analysis indicate that there has been a universal decrease in the duration of breast-feeding and postpartum abstinence, which has contributed to stalling and increasing fertility rates in countries of Central Africa. In other regions of the world, such as Southern Africa, Latin America & Caribbean and Asia, increased contraceptive use and increased age at marriage, or sexual debut, has been able to offset this, leading to substantial decreases in fertility rates. These findings should serve as a guide to where additional development policy and programmatic attention should focus to reduce too-high fertility in resource-poor settings.

Many industrialized nations are currently experiencing a decline in average secondary sex ratio (SSR) resulting in fewer boys being born relative to girls. While many potential factors may explain the decline in the birth of males relative to females, it seems most studies support the idea that male offspring are produced less often when environmental conditions are poor owing to males being more susceptible to loss in harsh environments. This study investigates the maternal factors that are associated with the sex of offspring in a cohort of the Australian population. It found that greater parental perceptions of wealth were significantly associated with an increase in the number of sons produced. These results suggest that male offspring are born at increased numbers to women with higher available resources, which may reflect the fact that male offspring are more vulnerable in poor environments.

This study examined the recent level, trends and determinants of consanguineous marriage in Jordan using time-series data from the Jordan Population and Family Health Surveys (JPFHSs). According to the 2012 JPFHS, 35% of all marriages were consanguineous in Jordan in 2012. There has been a declining trend in consanguinity in the country, with the rate decreasing from a level of 57% in 1990. Most consanguineous marriage in 2012 were first cousin marriages, constituting 23% of all marriages and 66% of all consanguineous marriages. The data show that women with a lower age at marriage, older marriage cohort, larger family size, less than secondary level of education, rural place of residence, no employment, no exposure to mass media, a monogamous marriage, a husband with less than higher level of education and lower economic status, and those from the Badia region, were more likely to have a consanguineous marriage. Increasing age at marriage, level of education, urbanization and knowledge about the health consequences of consanguinity, and the ongoing socioeconomic and demographic transition in the country, will be the driving forces for further decline in consanguinity in Jordan.