Age at menarche associated with subsequent educational attainment and risk-taking behaviours: the Pelotas 1982 Birth Cohort

Association Between Markers of Adiposity During Childhood and Puberty Onset in Latino Girls

CONTEXT

Prepubertal adiposity is associated with earlier puberty. It is unclear when this association starts, if all adiposity markers are similarly associated, and whether all pubertal milestones are similarly affected.

OBJECTIVE

To evaluate the association between different adiposity markers during childhood and the timing of different pubertal milestones in Latino girls.

DESIGN, SETTING, AND PARTICIPANTS

Longitudinal follow-up of 539 female participants of the Chilean Growth and Obesity Cohort recruited from childcare centers (mean age 3.5 years) from the southeast area of Santiago, Chile. Participants were singletons born between 2002 and 2003 within the normal birthweight range. Since 2006, a trained dietitian measured weight, height, waist circumference (WC) and skinfolds to estimate body mass index (BMI) Centers for Disease Control and Prevention percentiles, central obesity, percentage of fat mass (%FM), and fat mass index (FMI, fat mass/height2).

MAIN OUTCOME

Since 2009, sexual maturation was assessed every 6 months to assess age at (1) thelarche, (2) pubarche, (3) menarche, and (4) peak height velocity (PHV).

RESULTS

At thelarche, 12.5% were obese and 2% had central obesity. The median age of pubarche, menarche, and PHV were all associated with markers of adiposity at different time points during childhood whereas thelarche only with %FM and FMI. Adiposity clusters models showed that children with trajectories of high WC, %FM, and FMI during childhood were related with earlier thelarche, pubarche, menarche, and PHV but BMI trajectories only with menarche and PHV.

CONCLUSIONS

Higher WC, %FM, and FMI were associated with earlier age at thelarche, pubarche, menarche, and PHV. The effect of BMI was less consistent.

Association of Social Determinants of Health, Race and Ethnicity, and Age of Menarche among US Women Over 2 Decades

INTRODUCTION

Age of menarche (AOM), or the first menstrual cycle, is one indicator of female puberty. The timing of AOM can be influenced by social determinants of health (SDOH). This study examined associations between SDOH and AOM over the past 2 decades in the United States.

METHODS

US National Health and Nutrition Examination Survey data (1999 to early 2020) were analyzed. Multinomial logistic regression analyses examined associations between AOM (early [11.99 years and younger], typical [12-13 years], and late [13.01 years and older]) and race/ethnicity, insurance coverage, education, family income-to-poverty ratio, money management, and home status.

RESULTS

AOM remained consistent over the past 2 decades (mean 12.50 years, SE 0.02) for the aggregate sample. Females identifying as Hispanic (excluding Mexican Americans) were 63% more likely (adjusted odds ratio [aOR] 1.63, 95% confidence interval [CI] 1.13-2.36) to report early menarche. Those identifying as other/multiracial were 46% more likely to report late menarche (aOR 1.46, 95% CI 1.13-1.89) vs non-Hispanic Whites. Financial and home status instability was associated with early menarche (aOR 1.46, 95% CI 1.17-1.83; aOR 1.25, 95% CI 1.05-1.48). Less than 9th-grade education was associated with late menarche (aOR 1.47, 95% CI 1.14-1.89).

CONCLUSION

Although the average AOM has remained stable in the United States over the past 20 years, identifying as Hispanic (excluding Mexican Americans) and financial/home instability are associated with early AOM, and lower education levels are associated with late AOM. Identifying programming and policy options targeting SDOH may help improve current and future reproductive health.

Growth in Infancy and Childhood and Age at Menarche in Five Low- or Middle-Income Countries: Consortium of Health Orientated Research in Transitional Societies (COHORTS)

BACKGROUND

Earlier age at menarche is associated with behavioral and noncommunicable disease risks. The influence of birth weight (BW) (intrauterine) and postnatal growth on age at menarche is not well studied in low- and middle-income countries (LMICs).

OBJECTIVE

Therefore, we investigated these associations in 5 LMIC birth cohorts.

METHODS

We analyzed data from Brazil, Guatemala, India, the Philippines, and South Africa (n = 3983). We derived stunting (< -2 SD scores) at 24 mo using the WHO child growth standards. We generated interaction terms with categorized BW and conditional weight (lighter < 0 or heavier ≥ 0), and height (shorter < 0 or taller ≥ 0) z-scores. We categorized early-, modal-, and late-onset menarche and used multilevel ordinal regression. We used multilevel linear regression on continuous age at menarche.

RESULTS

Mean age at menarche was 12.8 y (95% CI: 12.7 12.9). BW was not associated with age at menarche. Conditional height at 24 mo and mid-childhood (OR: 1.35; 95% CI: 1.27, 1.44 and 1.32; 1.25, 1.41, respectively) and conditional weight at 24 mo and mid-childhood (OR: 1.15; 1.08, 1.22 and 1.18; 1.11, 1.25, respectively) were associated with increased likelihood of early-onset menarche. Being heavier at birth and taller at 24 mo was associated with a 4-mo (95% CI: 0.8, 7.6) earlier age at menarche than being lighter at birth and shorter at 24 mo. Being heavier at birth but lighter in mid-childhood was associated with a 3-mo (95% CI: 0.8, 4.8) later age at menarche than being lighter at birth and mid-childhood. Age at menarche was 7 mo later in stunted than nonstunted girls.

CONCLUSION

Age at menarche is inversely related to relative weight gain but also to rapid linear growth among those born shorter but remained stunted, and those born taller and grew excessively. These findings do not deter the global health goal to reduce growth faltering but emphasize the potential adverse effects of an obesogenic environment on adolescent development.

The Effects of Pubertal Timing on Academic Performance in Adolescence and Career Success in Adulthood: Evidence from a 16-year Longitudinal Study

Previous research showed inconsistent effects of pubertal timing on adolescent academic performance and adult career success. Moreover, the relative importance of biological vs. perceived pubertal timing has not been examined. This study examined effects of biological and perceived pubertal timing on academic performance throughout adolescence and career success in adulthood together with sex differences in an understudied population of pre-dominantly Black youth from lower income families. The sample included 704 youth (52% male, 76% Black, 22% White) interviewed at four time points (Mean ages: 11.8, 13.2, 17.6, and 27.7 years). The results from a mediation path model showed that among males, perceived off-time pubertal timing uniquely predicted lower concurrent academic performance as well as lower objective career success in adulthood; this effect was mediated by lower academic performance throughout adolescence. Additionally, results from bivariate correlation analyses showed associations between early biological pubertal timing and lower concurrent academic performance in males and early perceived pubertal timing and lower concurrent academic performance among females. These findings contribute to the understanding of more nuanced links between pubertal timing, academic performance and subsequent career success in an understudied population of pre-dominantly Black youth from lower income families.

Neurobiology of puberty and its disorders

Puberty, which in humans is considered to include both gonadarche and adrenarche, is the period of becoming capable of reproducing sexually and is recognized by maturation of the gonads and development of secondary sex characteristics. Gonadarche referring to growth and maturation of the gonads is fundamental to puberty since it encompasses increased gonadal steroid secretion and initiation of gametogenesis resulting from enhanced pituitary gonadotropin secretion, triggered in turn by robust pulsatile GnRH release from the hypothalamus. This chapter reviews the development of GnRH pulsatility from before birth until the onset of puberty. In humans, GnRH pulse generation is restrained during childhood and juvenile development. This prepubertal hiatus in hypothalamic activity is considered to result from a neurobiological brake imposed upon the GnRH pulse generator resident in the infundibular nucleus. Reactivation of the GnRH pulse generator initiates pubertal development. Current understanding of the genetics and physiology of the brake will be discussed, as will hypotheses proposed to account for timing the resurgence in pulsatile GnRH and initiation of puberty. The chapter ends with a discussion of disorders associated with precocious or delayed puberty with a focus on those with etiologies attributed to aberrant GnRH neuron anatomy or function. A pediatric approach to patients with pubertal disorders is provided and contemporary treatments for both precocious and delayed puberty outlined.