Declining ages at menarche in an agrarian rural region of Poland

Secular Trends in the Median Age at Menarche and Spermarche Among Chinese Children From 2000 to 2019 and Analysis of Physical Examination Indicators Factor

OBJECTIVES

This research aimed to understand the long-term trends in the age of menarche among girls and spermarche among boys, and to analyze the factors that may influence the onset of menarche and first spermarche.

METHODS

The study was based on data from 49 566 students in Henan Province collected from the Chinese National Surveys on Students' Constitution and Health (CNSSCH) conducted between 2000 and 2019. Median age at menarche and spermarche was estimated by probit analysis. t-Tests were used to analyze the influence of menarche and first spermarche on physical examination indexes of adolescent children, and the chi-squared test was used to compare whether the differences in physical activity were statistically significant.

RESULTS

The age at menarche has decreased from 12.33 years in 2000 to 12.00 years in 2019, and the age at first spermarche has decreased from 14.01 years in 2000 to 13.99 years in 2019. The age at first spermarche in urban boys (13.61 years in 2000; 12.94 years in 2014) was consistently younger than that in rural boys (14.43 years in 2000; aged 13.08 in 2014), except in 2019. The age of menarche in urban girls (12.23 years in 2000; 11.89 years in 2019) was always earlier than that in rural girls (12.44 years in 2000; 12.05 years in 2019).

CONCLUSIONS

The age at menarche and spermarche for children in Henan Province generally showed a decreasing trend from 2000 to 2019. The status of BMI is significantly associated with the early onset of puberty in children.

Dietary Protein Source Matters for Changes in Inflammation Measured by Urinary C-Reactive Protein in Rural Polish Women

Objectives

Multiple macronutrients have been shown to affect systemic inflammation, a well-known predictor of chronic disease. Less often, varying sources of these macronutrients are examined. Different subsistence environments lead to varying access to protein sources which, combined with physical activity patterns, may lead to different relationships than among more typically studied sedentary, industrialized populations. This study hypothesizes an association between dietary protein intake and urinary C-Reactive Protein (CRP) concentration in women from a rural, agrarian Polish community.

Materials and Methods

We assessed protein intake and their sources for 80 nonsmoking, premenopausal Polish women who were not pregnant, nursing, or on hormonal birth control during the study or within the previous six months. Each participant completed multiple 24-hour dietary recalls during one menstrual cycle. Participants collected morning void urinary samples daily over one menstrual cycle for urinary CRP analysis. We analyzed relationships between plant and animal protein intake and CRP over the menstrual cycle by multiple linear regression.

Results

Plant protein in cereal foods was significantly positively associated with cycle-average urinary CRP concentrations (p<0.05) after controlling for body fat percent, total energy intake, and dietary fiber. Foods containing animal protein were not significantly associated with CRP.

Discussion

Contents of this population's main plant and animal protein sources differ from those of more commonly studied industrialized populations. Within the context of a population's typical diet, more emphasis may need to be placed on particular source of protein consumed, beyond plant versus animal, in order to understand relationships with CRP.

Secular trends of age at menarche and the effect of famine exposure on age at menarche in rural Chinese women

BACKGROUND

Over the past few decades, more studies have suggested that the age at menarche (AAM) has continued to decline. However, the AAM for women in resource-constrained areas is not clear. Moreover, the association between the China famine and AAM is still unclear in rural regions.

AIM

The study aimed to investigate the secular trends of AAM for women born between 1935 and 2000 and to further explore the effect of famine on AAM in rural China.

SUBJECTS AND METHODS

The study included 23444 women participants from the baseline study of Henan Rural Cohort study. Changing AAM over time was analysed using linear regressions. Multinomial logistic regression was conducted to analyse the association between famine exposure and AAM subgroups.

RESULTS

The age-standardized mean AAM was 14.74 years. The average AAM declined from 16.98 years for those born in 1935 to 13.87 years for those born in 2000, a decline of 0.077 years per 1 year and 0.729 years per decade. Compared to the reference group, women exposed to famine during fetal, early childhood, middle childhood, and late childhood were 1.376 (95% CI, 1.071 - 1.769), 1.848(95% CI, 1.512 - 2.259), 2.084(95% CI, 1.725 - 2.518), and 2.146 (95% CI, 1.788 - 2.576) times more likely to be ≥18 years of AAM than unexposed famine women, respectively.

CONCLUSION

AAM showed a decreasing trend in rural China. Furthermore, both fetal and childhood famine exposure, especially in late childhood, were positively associated with increased AAM compared to unexposed famine.

Inflammaging: Blame the sons. Relationships between the number of sons and the level of inflammatory mediators among post-reproductive women

OBJECTIVES

Reproduction is costly, but sons and daughters differently influence maternal physiology, also in older age. In particular, having sons may negatively influence maternal health and may be associated with a shorter life span of mothers. Sons may also contribute to increased inflammaging, a chronic sub-clinical systemic inflammatory state characterized by elevated levels of serum inflammatory mediators. The aim of this study was to examine the impact of the total number of children, and the number of daughters and sons separately on concentrations of C-reactive protein (CRP), and proinflammatory cytokines such as interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α).

MATERIALS AND METHODS

The participants were 378 women aged 45-92 who had 3.9 (SD 2.12, median = 4, range = 0-13) children, including 2.1 (SD 1.46, median = 2, range = 0-8) sons and 1.8 (SD 1.44, median = 2, range = 0-7) daughters on average.

RESULTS

We found a positive relationship between the overall number of children and IL-6 levels. CRP and IL-6 concentrations were positively associated with the number of sons but not with the number of daughters. Each son increased maternal CRP level by 11%, and IL-6 level by 6%. Neither the total number of children nor the number of daughters or sons were related to the TNF-α concentration.

DISCUSSION

Aging-associated inflammation in post-reproductive mothers with a higher number of sons supports the hypothesis of trade-offs between reproduction and health. Furthermore, these results provide new evidence contributing to the idea that having sons may have more detrimental effects on the maternal organism than having daughters.