Comparison of Clinical, Maternal, and Self Pubertal Assessments: Implications for Health Studies

Temporal relation between pubertal development and peer victimization in a prospective sample of US adolescents

Peer victimization typically peaks in early adolescence, leading researchers to hypothesize that pubertal timing is a meaningful predictor of peer victimization. However, previous methodological approaches have limited our ability to parse out which puberty cues are associated with peer victimization because gonadal and adrenal puberty, two independent processes, have either been conflated or adrenal puberty timing has been ignored. In addition, previous research has overlooked the possibility of reverse causality-that peer victimization might drive pubertal timing, as it has been shown to do in non-human primates. To fill these gaps, we followed 265 adolescents (47% female) prospectively across three-time points (Mage : T1 = 9.6, T2 = 12.0, T3 = 14.4) and measured self-report peer victimization and self- and maternal-report of gonadal and adrenal pubertal development on the Pubertal Development Scale. Multilevel modeling revealed that females who were further along in adrenal puberty at age 9 were more likely to report peer victimization at age 12 (Cohen's d = 0.25, p = .005). The relation between gonadal puberty status and peer victimization was not significant for either sex. In terms of the reverse direction, the relation between early peer victimization and later pubertal development was not significant in either sex. Overall, our findings suggest that adrenal puberty status, but not gonadal puberty status, predicted peer victimization in females, highlighting the need to separate gonadal and adrenal pubertal processes in future studies.

Validity and reliability of parent assessments of pubertal maturation among adolescent girls in Isfahan, Iran

OBJECTIVES

The current paper presents the steps considered for validation of a questionnaire for assessment of sexual maturity among Iranian adolescent girls.

METHODS

This cross-sectional study was performed in 2022 in Isfahan, Iran. Based on the Growth and Development Questionnaire that included both the Pubertal Development Scale (PDS) and Sexual Maturation Scale (SMS), two Persian questionnaires were prepared. The face validity, content validity, criterion validity, and reliability of the questionnaire were assessed. We compared agreement of two parent-reported measures of puberty, SMS and PDS, with clinical Tanner stages (TSs) as the gold standard. Percent agreement, Cohen's kappa coefficient, and Kendall's τ b were used to assess the agreement between maternal assessments with clinical TS. The intraclass correlation coefficient (ICC) and the Cronbach's α coefficient were also calculated to evaluate the reliability of the questionnaire.

RESULTS

A total of 150 students aged 6-17 years with mean (SD) age of 10 (2.04) completed this study. The percentages of agreement for the mother-reported SMS in relation to clinical TS for breast stage and pubic hair stage were 60 % and 53.8 %, respectively. The percentages of agreement of the mother-reported PDS in relation to clinical TS for breast stage and pubic hair stage were 55.8 and 66 %, respectively. The weighted kappa coefficients showed moderate agreement, with weighted kappa ranging from 0.52 to 0.61. The mother-reported SMS and PDS showed high reliability. The Cronbach's alpha of the PDS and the SMS was 0.88 and 0.83, respectively. The ICC of the mother-reported SMS and the mother-reported PDS was 0.95 (0.92-0.98) and 0.97 (0.94-0.98), respectively.

CONCLUSIONS

This study indicated that a maternal assessment of sexual maturity using the PDS or SMS can reliably estimate pubertal development in adolescent girls in an Iranian population.

Mothers' prenatal distress accelerates adrenal pubertal development in daughters

Human life history schedules vary, partly, because of adaptive, plastic responses to early-life conditions. Little is known about how prenatal conditions relate to puberty timing. We hypothesized that fetal exposure to adversity may induce an adaptive response in offspring maturational tempo. In a longitudinal study of 253 mother-child dyads followed for 15 years, we investigated if fetal exposure to maternal psychological distress related to children's adrenarche and gonadarche schedules, assessed by maternal and child report and by dehydroepiandrosterone sulfate (DHEA-S), testosterone, and estradiol levels. We found fetal exposure to elevated maternal prenatal psychological distress predicted earlier adrenarche and higher DHEA-S levels in girls, especially first-born girls, and that associations remained after covarying indices of postnatal adversity. No associations were observed for boys or for gonadarche in girls. Adrenarche orchestrates the social-behavioral transition from juvenility to adulthood; therefore, significant findings for adrenarche, but not gonadarche, suggest that prenatal maternal distress instigates an adaptive strategy in which daughters have earlier social-behavioral maturation. The stronger effect in first-borns suggests that, in adverse conditions, it is in the mother's adaptive interest for her daughter to hasten social maturation, but not necessarily sexual maturation, because it would prolong the duration of the daughter allomothering younger siblings. We postulate a novel evolutionary framework that human mothers may calibrate the timing of first-born daughters' maturation in a way that optimizes their own reproductive success.

Childhood physical activity and pubertal timing: findings from the LEGACY girls study

BACKGROUND

There is limited research on whether physical activity (PA) in early childhood is associated with the timing of pubertal events in girls.

METHODS

We used data collected over 2011-16 from the LEGACY Girls Study (n = 984; primarily aged 6-13 years at study enrolment), a multicentre North American cohort enriched for girls with a breast cancer family history (BCFH), to evaluate if PA is associated with age at thelarche, pubarche and menarche. Maternal-reported questionnaire data measured puberty outcomes, PA in early childhood (ages 3-5 years) and total metabolic equivalents of organized PA in middle childhood (ages 7-9 years). We used interval-censored Weibull parametric survival regression models with age as the time scale and adjusted for sociodemographic factors, and we tested for effect modification by BCFH. We used inverse odds weighting to test for mediation by body mass index-for-age z-score (BMIZ) measured at study enrolment.

RESULTS

Being highly active vs inactive in early childhood was associated with later thelarche in girls with a BCFH [adjusted hazard ratio (aHR) = 0.39, 95% CI = 0.26-0.59), but not in girls without a BCFH. In all girls, irrespective of BCFH, being in the highest vs lowest quartile of organized PA in middle childhood was associated with later menarche (aHR = 0.70, 95% CI = 0.50-0.97). These associations remained after accounting for potential mediation by BMIZ.

CONCLUSION

This study provides new data that PA in early childhood may be associated with later thelarche in girls with a BCFH, also further supporting an overall association between PA in middle childhood and later menarche.

Urinary Androgens Provide Additional Evidence Related to Metabolism and Are Correlated With Serum Androgens in Girls

Context

Androgen levels are generally measured in serum samples, but urine may be a more feasible option, especially in children, as it is a noninvasive alternative.

Objective

To assess the correlations of 10 urinary androgen metabolites with 4 serum androgens [dehydroepiandrosterone-sulfate (DHEA-S), androstenedione, and total and free testosterone] and assess if their correlations differ by participant characteristics.

Methods

Our study consisted of 44 girls, ages 6-13, who participated in the New York site of the LEGACY Girls Study and had both serum and urine samples collected at the same visit. We performed Pearson's correlation coefficient tests between 4 serum and 10 individual urinary metabolite measures and their sum. We examined the influence of participant characteristics on the magnitude and direction of the correlations.

Results

The summed urinary metabolite measures had the highest correlation with free testosterone in serum (global sum, r = 0.83) and correlated least with DHEA-S in serum (global sum, r = 0.64). The correlation between individual urinary metabolites and serum androgens ranged from 0.08 to 0.84.Two 11-oxygenated urinary metabolites (5α-androstane-3α-ol-11,17-dione5β-androstane-3α,11β-diol-17-one) were weakly correlated with all serum androgens. Participant age, weight, height, waist:hip ratio, and pubic hair growth stage changed the correlations between urinary and serum androgens measures between 10% and 213%.

Conclusion

The sum of urinary androgen metabolites was a good marker of circulating androstenedione, testosterone, and free testosterone. Individual urinary metabolites provide additional information about the metabolic processes of disease development compared to the antecedent serum androgens.

Puberty Assessment and Consideration of Gonadotropin-Releasing Hormone Agonists in Transgender and Gender-Diverse Youth

Transgender and gender-diverse (TGD) youth may pursue gender-affirming medical therapy in the form of gonadotropin-releasing hormone analogues (GnRHa), or "puberty blockers," if pubertal changes result in the development or worsening of gender dysphoria. GnRHa monotherapy can allow TGD youth to explore gender without the distress of unwanted secondary sexual characteristics. However, given the potential effects of GnRHa on growth, skeletal development, neurodevelopment, fertility, and future surgical outcomes, it is critical to accurately assess pubertal status to facilitate fully informed conversations with TGD youth and families about risks, benefits, and unknown consequences of GnRHa monotherapy. The focus of this discussion will be on the approach to puberty assessment in TGD youth as well as the different effects of GnRHa monotherapy that may be important to TGD youth and their families. [Pediatr Ann. 2023;52(12):e462-e466.].

Immigrant generation status and its association with pubertal timing and tempo among Hispanic girls and boys

PURPOSE

In the United States, Hispanic-Latino children reach puberty earlier on average than non-Hispanic white children. Yet among U.S. Hispanic/Latino children, pubertal timing comparisons between immigrant generations have not been made, hence we examined whether pubertal timing differs by immigrant generational status, independent of BMI and acculturation measures.

METHODS

Cross-sectional data on 724 boys and 735 girls, aged 10-15 years, from the Hispanic Community Children's Health Study/Study of Latino (SOL) Youth, were used to predict the median ages of thelarche, pubarche, and menarche in girls, and pubarche and voice change in boys, using Weibull survival models, while adjusting for SOL center, BMI, and acculturation.

RESULTS

In girls, the first generation began thelarche earlier than second and third generations (median age [years] [95% confidence interval]: 7.4 [6.1, 8.8] vs. 8.5 [7.3, 9.7] and 9.1 [7.6, 10.7], respectively), but began menarche later (12.9 [12.0,137] vs. 11.8 [11.0, 12.5] and 11.6 [10.6, 12.6], respectively). Pubertal timing and tempo for boys did not differ by generational status.

CONCLUSIONS

First-generation U.S. Hispanic/Latino girls had the earliest thelarche, latest menarche and longest pubertal tempo, compared to second and third generations. Factors beyond BMI and acculturation may account for the differences in pubertal timing by generational status of U.S. Hispanic/Latino girls.

Urinary Biomarkers of Polycyclic Aromatic Hydrocarbons and Timing of Pubertal Development: The California PAH Study

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) are endocrine-disrupting chemicals. Few studies have evaluated the association between pubertal development in girls and PAH exposures quantified by urinary biomarkers.

METHODS

We examined associations of urinary PAH metabolites with pubertal development in 358 girls 6-16 years of age from the San Francisco Bay Area enrolled in a prospective cohort from 2011 to 2013 and followed until 2020. Using baseline data, we assessed associations of urinary PAH metabolites with pubertal development stage. In prospective analyses limited to girls who at baseline had not yet started breast (N = 176) or pubic hair (N = 179) development or menstruation (N = 267), we used multivariable Cox proportional hazards regression to assess associations of urinary PAH metabolites with the onset of breast and pubic hair development, menstruation, and pubertal tempo (interval between the onset of breast development and menstruation).

RESULTS

We detected PAH metabolites in >98% of girls. In cross-sectional analyses using baseline data, PAH metabolites were not associated with the pubertal development stage. In prospective analyses, higher concentrations (≥ median) of some PAH metabolites were associated with two-fold higher odds of earlier breast development (2-hydroxy naphthalene, 1-hydroxy phenanthrene, summed hydroxy phenanthrenes) or pubic hair development (1-hydroxy naphthalene) among girls overweight at baseline (body mass index-for-age percentile ≥85) compared with nonoverweight girls with lower metabolites concentrations. PAH metabolites were not associated with age at menarche or pubertal tempo.

CONCLUSIONS

PAH exposures were widespread in our sample. Our results support the hypothesis that, in overweight girls, PAHs impact the timing of pubertal development, an important risk factor for breast cancer.

Maternal and prenatal factors and age at thelarche in the LEGACY Girls Study cohort: implications for breast cancer risk

BACKGROUND

Earlier onset of breast development (thelarche) is associated with increased breast cancer risk. Identifying modifiable factors associated with earlier thelarche may provide an opportunity for breast cancer risk reduction starting early in life, which could especially benefit girls with a greater absolute risk of breast cancer due to family history.

METHODS

We assessed associations of maternal pre-pregnancy body mass index (BMI), physical activity during pregnancy, gestational weight gain and daughters' weight and length at birth with age at thelarche using longitudinal Weibull models in 1031 girls in the Lessons in Epidemiology and Genetics of Adult Cancer from Youth (LEGACY) Girls Study-a prospective cohort of girls, half of whom have a breast cancer family history (BCFH).

RESULTS

Girls whose mothers had a pre-pregnancy BMI of ≥25 and gained ≥30 lbs were 57% more likely to experience earlier thelarche than girls whose mothers had a pre-pregnancy BMI of <25 and gained <30 lbs [hazard ratio (HR) = 1.57, 95% CI: 1.16, 2.12]. This association was not mediated by childhood BMI and was similar in girls with and without a BCFH (BCFH: HR = 1.41, 95% CI: 0.87, 2.27; No BCFH: HR = 1.62, 95% CI: 1.10, 2.40). Daughters of women who reported no recreational physical activity during pregnancy were more likely to experience earlier thelarche compared with daughters of physically active women. Birthweight and birth length were not associated with thelarche.

CONCLUSION

Earlier thelarche, a breast cancer risk factor, was associated with three potentially modifiable maternal risk factors-pre-pregnancy BMI, gestational weight gain and physical inactivity-in a cohort of girls enriched for BCFH.

Body mass index rebound and pubertal timing in girls with and without a family history of breast cancer: the LEGACY girls study

BACKGROUND

Heavier body mass index (BMI) is the most established predictor of earlier age at puberty. However, it is unknown whether the timing of the childhood switch to heavier BMI (age at BMI rebound) also matters for puberty.

METHODS

In the LEGACY Girls Study (n = 1040), a longitudinal cohort enriched with girls with a family history of breast cancer, we collected paediatric growth chart data from 852 girls and assessed pubertal development every 6 months. Using constrained splines, we interpolated individual growth curves and then predicted BMI at ages 2, 4, 6, 8 and 9 years for 591 girls. We defined age at BMI rebound as the age at the lowest BMI between ages 2 and 8 years and assessed its association with onset of thelarche, pubarche and menarche using Weibull survival models.

RESULTS

The median age at BMI rebound was 5.3 years (interquartile range: 3.6-6.7 years). A 1-year increase in age at BMI rebound was associated with delayed thelarche (HR = 0.90; 95% CI = 0.83-0.97) and menarche (HR = 0.86; 95% CI = 0.79-0.94). The magnitude of these associations remained after adjusting for weight between birth and 2 years, was stronger after adjusting for BMI at age 9, and was stronger in a subset of girls with clinically assessed breast development.

CONCLUSIONS

Earlier BMI rebound is associated with earlier pubertal timing. Our observation that BMI rebound may be a driver of pubertal timing in girls with and without a family history of breast cancer provides insight into how growth and pubertal timing are associated with breast cancer risk.

Comparing adolescent self staging of pubertal development with hormone biomarkers

OBJECTIVES

Physical examinations to characterize pubertal maturation may be unacceptable for children enrolled in research studies. Studies confirm the utility of pubertal self staging for research, but there has been limited comparison of self examination with hormone biomarkers. Our objective was to assess concordance of pubertal self staging with hormone biomarkers of puberty.

METHODS

Participants were enrolled in the Health Outcomes and Measures of the Environment Study, a longitudinal pregnancy and birth cohort study. At age 12 years, 139 females and 112 males completed pubertal self staging including breast and pubic hair development in females and pubic hair development in males. No clinical physical examination was performed. Hormone concentrations were measured in 102 females and 96 males including serum dehydroepiandrosterone sulfate, luteinizing hormone, and follicle-stimulating hormone in all; estradiol in females; and testosterone in males.

RESULTS

Estradiol was significantly associated with female breast stage, even when adjusted for BMI, with geometric least squares means (95%CI) of 13.2 (8.7, 20.2), 38.3 (29.9, 49.1), 59.4 (39.8, 88.6), and 81.2 (45.6, 144) pg/mL for breast stage 1-2, 3, 4, and 5, respectively. Testosterone was significantly associated with male pubic hair stage, with adjusted geometric least squares means (95%CI) of 37.6 (19.9, 71.1), 43.4 (27.7, 68.3), 126 (78.4, 203), 275 (146, 521), and 559 (237, 1319) ng/dL for pubic hair stage 1, 2, 3, 4, and 5, respectively.

CONCLUSIONS

Self assessed pubertal development was positively associated with hormonal biomarkers of puberty.

Prospective associations of mid-childhood plasma per- and polyfluoroalkyl substances and pubertal timing

BACKGROUND

Exposure to per- and polyfluoroalkyl substances (PFAS) may disrupt pubertal timing. Higher PFAS plasma concentrations have been associated with later pubertal timing in girls, but cross-sectional findings may be explained by reverse causation.

OBJECTIVES

To assess prospective associations between PFAS plasma concentrations in mid-childhood and markers of pubertal timing in male and female adolescents.

METHODS

We studied 640 children in Project Viva, a Boston-area prospective cohort. We examined associations of plasma concentrations of 6 PFAS measured at mean 7.9 (SD 0.8) years (2007-2010) with markers of pubertal timing. Parents reported a 5-item pubertal development score at early adolescence (mean 13.1 (SD 0.8) years) and reported age at menarche annually. We calculated age at peak height velocity using research and clinical measures of height. We used sex-specific linear and Cox proportional hazards regression to estimate associations of single PFAS with outcomes, and we used Bayesian Kernel Machine Regression (BKMR) to estimate associations of the PFAS mixture with outcomes.

RESULTS

Plasma concentrations were highest for perfluorooctane sulfonate (PFOS) [median (IQR) 6.4(5.6) ng/mL], followed by perfluorooctanoate (PFOA) [4.4(3.0) ng/mL]. In early adolescence, girls were further along in puberty than boys [pubertal development score mean (SD) 2.9 (0.7) for girls and 2.2(0.7) for boys; age at peak height velocity mean (SD) 11.2y (1.0) for girls and 13.1y (1.0) for boys]. PFAS was associated with later markers of pubertal timing in girls only. For example, each doubling of PFOA was associated with lower pubertal development score (-0.18 units; 95% CI: -0.30, -0.06) and older age at peak height velocity (0.23 years; 95% CI: 0.06, 0.40)]. We observed similar associations for PFOS, perfluorodecanoate (PFDA), and the PFAS mixture. PFAS plasma concentrations were not associated with age at menarche or markers of pubertal timing in boys.

DISCUSSION

Higher PFAS plasma concentrations in mid-childhood were associated with later onset of puberty in girls.

Common Childhood Viruses and Pubertal Timing: The LEGACY Girls Study

Earlier pubertal development is only partially explained by childhood body mass index; the role of other factors, such as childhood infections, is less understood. Using data from the LEGACY Girls Study (North America, 2011-2016), we prospectively examined the associations between childhood viral infections (cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) 1, HSV2) and pubertal timing. We measured exposures based on seropositivity in premenarcheal girls (n = 490). Breast and pubic hair development were classified based on mother-reported Tanner Stage (TS) (TS2+ compared with TS1), adjusting for age, body mass index, and sociodemographic factors. The average age at first blood draw was 9.8 years (standard deviation, 1.9 years). The prevalences were 31% CMV+, 37% EBV+, 14% HSV1+, 0.4% HSV2+, and 16% for both CMV+/EBV+ coinfection. CMV+ infection without coinfection was associated with developing breasts an average of 7 months earlier (hazard ratio (HR) = 2.12, 95% confidence interval (CI): 1.32, 3.40). CMV infection without coinfection and HSV1 and/or HSV2 infection were associated with developing pubic hair 9 months later (HR = 0.41, 95% CI: 0.24, 0.71, and HR = 0.42, 95% CI: 0.22, 0.81, respectively). Infection was not associated with menarche. If replicated in larger cohorts with blood collection prior to any breast development, this study supports the hypothesis that childhood infections might play a role in altering pubertal timing.

Prepubertal Internalizing Symptoms and Timing of Puberty Onset in Girls

Stressful environments have been associated with earlier menarche. We hypothesized that anxiety, and possibly other internalizing symptoms, are also associated with earlier puberty in girls. The Lessons in Epidemiology and Genetics of Adult Cancer From Youth (LEGACY) Girls Study (2011-2016) included 1,040 girls aged 6-13 years at recruitment whose growth and development were assessed every 6 months. Prepubertal maternal reports of daughter's internalizing symptoms were available for breast onset (n = 447), pubic hair onset (n = 456), and menarche (n = 681). Using Cox proportional hazard regression, we estimated prospective hazard ratios and 95% confidence intervals for the relationship between 1 standard deviation of the percentiles of prepubertal anxiety, depression, and somatization symptoms and the timing of each pubertal outcome. Multivariable models included age, race/ethnicity, study center, maternal education, body mass index percentile, and family history of breast cancer. Additional models included maternal self-reported anxiety. A 1-standard deviation increase in maternally reported anxiety in girls at baseline was associated with earlier subsequent onset of breast (hazard ratio (HR) = 1.22, 95% confidence interval (CI): 1.09, 1.36) and pubic hair (HR = 1.15, 95% CI: 1.01, 1.30) development, but not menarche (HR = 0.94, 95% CI: 0.83, 1.07). The association of anxiety with earlier breast development persisted after adjustment for maternal anxiety. Increased anxiety in young girls may indicate risk for earlier pubertal onset.

Onset of Puberty: Mother Knows Best

STUDY OBJECTIVE

Several strategies have been proposed to determine onset of puberty without examination by a trained professional. This study sought to evaluate a novel approach to determine onset of puberty in girls.

DESIGN, SETTING, AND PARTICIPANTS

This study used the Cincinnati cohort of the Breast Cancer and the Environment Research Program. Girls were recruited at 6-7 years of age and followed every 6 months in the initial 6 years, and annually thereafter. Breast maturation and foot length were performed at each visit by health professionals certified in those methods. Mothers were asked to provide the age at which they believed that their daughter's shoe size had increased more rapidly.

RESULTS

These analyses include 252 participants. Age at increase in shoe size was correlated to age at onset of puberty (r = 0.21) and increase in foot length (r = 0.24). The difference of reported age of increased shoe size was 0.46 years before breast development.

CONCLUSION

Reported increase in shoe size occurred somewhat earlier and was significantly correlated to age of breast development. These preliminary results suggest that mother's report of increase in shoe size appear to be as accurate as reports of other indirect methods of determining onset of puberty, such as self- or maternal estimates of breast development.

Influence of pubertal development on urinary oxidative stress biomarkers in adolescent girls in the New York LEGACY cohort

Puberty is a time of intense growth and differentiation of breast tissue and a window of susceptibility (WOS) for breast cancer. Although oxidative stress markers have been associated with breast cancer risk, it is unclear whether oxidative stress levels are different during the pubertal WOS, and if so, whether these differences are related to breast cancer susceptibility. We measured urinary biomarkers of whole body oxidative stress (urinary F2-Isoprostanes and 8-oxodeoxyguanosine (8-oxodG)) in 158 girls (ages 6-13 years), 71 with and 87 without a breast cancer family history (BCFH) from a cohort of adolescent girls from the New York site of the LEGACY cohort (Lessons in Epidemiology and Genetics in Adults Cancer from Youth). We compared levels of urinary oxidative stress biomarkers (F2-Isoprostanes and 8-oxodG) across the pubertal window, defined by Tanner Stage (TS) of breast development, both cross-sectionally and longitudinally within girls over an 18-month follow up period. Urinary oxidative stress biomarkers were unrelated to pubertal stages in cross-sectional analyses after considering adjustments for body mass index (BMI) and BCFH. In our longitudinal analysis, we found that urinary 8-oxodG levels, but not F2-Isoprostane levels, increased with age in BCFH + girls (β = 6.12, 95% CI = 0.08-12.16) compared to BCFH-girls. Higher BMI was associated with higher level of F2-Isoprostane in both cross-sectional (β = 0.02, 95% CI = 0.0004-0.05) and longitudinal analysis (β = 0.02, 95% CI = 0.0002-0.05). These findings support that higher BMI increases oxidative stress biomarkers over the pubertal window and that there are changes in 8-oxodG oxidative stress biomarkers in girls with a BCFH compared to girls without a BCFH.

Correspondence of Pubertal Neuroendocrine and Tanner Stage Changes in Boys and Associations With Substance Use

This study examined correspondence between timing (onset) and tempo (rate) of sexual maturation prospectively (average ages 11-16 years) measured by gonadal hormones and secondary sex characteristics (Tanner stage) using dual-process models, and associations of these measures with substance use (SU) involvement in boys at age 16 years (N = 534, 77.5% White/22.5% Non-White). All measures of timing were highly associated. Early Tanner stage timing often predicted slower increases in gonadal steroids, but not the reverse; patterns varied by ethnicity. Hormone and Tanner stage measures were similar earlier in development but diverged later in development. In White boys only, early timing of the pubertal rise in testosterone was associated with increased SU involvement, suggesting a physiological rather than psychosocial mechanism of association.

Foot Length Growth as a Novel Marker of Early Puberty

Foot growth is part of overall pubertal growth but its relation to other anthropometric and hormonal changes is unclear. Our objective was to determine how foot length changes relate to changes in other growth parameters (height and weight), Tanner stage, and serum hormones. Adolescents (n = 342) were recruited to a 3-year longitudinal cohort study, underwent annual anthropometric assessments (height, weight, and foot length), and provided self-rated Tanner staging. They also provided blood samples that were analyzed using liquid chromatography-tandem mass spectrometry for serum testosterone and estradiol and classified as pre-pubertal or pubertal based on circulating hormone levels. Average annual percent increase in foot length was greater for pre-pubertal adolescents compared with pubertal. Increased foot length was associated with increases in height, weight, Tanner stage, and serum hormones in males and pre-menarcheal females but not post-menarcheal females. Foot length offers a novel, noninvasive, cost-effective, and easily demonstrable marker of early pubertal changes.

Size at birth, infant growth, and age at pubertal development in boys and girls

Purpose

This study investigated whether size at birth and infant growth were associated with age of indicators of pubertal development in boys and girls. We hypothesized that restricted fetal growth and accelerated infant growth lead to earlier pubertal age.

Patients and methods

In total, 15,822 boys and girls answered questionnaires half-yearly with information on pubertal development: age at menarche, first ejaculation, voice break, Tanner stages, axillary hair, and acne. Birth weight and gestational age were used to calculate birth weight Z-scores. Changes in infant weight Z-score from 0 to 5, 5 to 12, and 0 to 12 months were estimated. We estimated the mean monthly difference in timing of puberty between children born small-for-gestational age (SGA) and large-for-gestational age (LGA) with children born appropriate-for-gestational age (AGA) as reference. We further investigated whether increasing infant weight Z-scores were associated with age at attaining indicators of pubertal development.

Results

Girls born SGA reached all pubertal markers at an earlier mean age than girls born AGA, as indicated by mean age differences below zero (eg, age at menarche: -2.3 months, 95% CI: -3.4, -1.2), except for breast development. Girls born LGA reached pubertal markers later than girls born AGA (eg, age at menarche: 1.7 months, 95% CI 0.5, 2.9). Boys born SGA and LGA achieved puberty earlier than boys born AGA, though with CIs crossing zero (eg, age at voice break for SGA: -0.7 months, 95% CI -2.1, 0.7 and for LGA: -0.7 months, 95% CI -2.1, 0.8). A 1-unit increase in weight Z-score from 0 to 12 months was associated with a mean age difference of -1.7 to -0.3 months for pubertal development in both sexes.

Conclusion

Small size at birth and rapid infant growth were associated with early pubertal age, most consistent and pronounced in girls.

Associations of Maternal Gestational Weight Gain and Obesity With the Timing of Pubertal Onset in Daughters

Early puberty is associated with adverse health outcomes, but little is known regarding early-life determinants influencing pubertal timing. We examined the associations between maternal gestational weight gain (GWG) and the timing of the onset of breast development (thelarche) and pubic hair development (pubarche) in a cohort of 2,070 girls born in a Kaiser Permanente Northern California facility between 2005 and 2006. Using Weibull regression models accommodating interval censoring and adjusting for important confounders, we found that excess GWG was associated with increased risk of early thelarche (hazard ratio (HR) = 1.50, 95% confidence interval (CI): 1.26, 1.78) and early pubarche (HR = 1.35, 95% CI: 1.10, 1.66). Inadequate GWG was associated with early thelarche (HR = 1.36, 95% CI: 1.08, 1.71). The associations between excess or inadequate GWG and risk of earlier thelarche were stronger if mothers were obese before or at the beginning of pregnancy (body mass index ≥30 kg body weight per m height squared) (HR = 2.01, 95% CI: 1.53, 2.63; HR = 2.08, 95% CI: 1.45, 2.98, respectively). Similar associations were found for pubarche outcome. Inclusion of girls' prepubertal body mass index slightly attenuated these associations, but they remained significant. Monitoring of maternal weight before and throughout pregnancy might help prevent early pubertal onset and subsequent negative health outcomes.

Self-rated Tanner stage and subjective measures of puberty are associated with longitudinal gonadal hormone changes

Introduction In large community-based studies of puberty, Tanner staging by a clinician is often not possible. We compared self-rated Tanner staging and other subjective ratings of pubertal development with serum hormone levels measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to reassess the utility of self-rated pubertal stage using highly sensitive and specific hormone analysis. Methods Adolescents and their parents enrolled in the Adolescent Rural Cohort study of Hormones and health, Education, environments and Relationships (ARCHER) answered annual survey questions on pubertal development. Annually, adolescents provided blood samples for serum testosterone and estradiol measured by LC-MS/MS. Results Longitudinally, self-rated Tanner stage was positively associated with serum testosterone and estradiol levels in both sexes. Confirmation by adolescent and parent that puberty had commenced was associated with higher gonadal hormone levels in both sexes. Parent and adolescent responses demonstrated 'fair' to 'moderate' agreement. Conclusions Over a 3-year follow-up, self-rated Tanner staging and simple questions regarding pubertal onset and development are positively associated with adolescent gonadal hormone concentrations in serum measured by mass spectrometry. Thus, self-report of puberty stage still has a role in large community-based studies where physical examination is not feasible.

Pubertal influences on neural activation during risky decision-making in youth with ADHD and disruptive behavior disorders

OBJECTIVE

Risk-taking during adolescence is a leading cause of mortality; Neuroscience research examining pubertal effects on decision-making is needed to better inform interventions, particularly among youth with attention-deficit/hyperactivity (ADHD) and disruptive behavior disorders (DBD), who are particularly prone to risky decision-making. We examined effects of pubertal development on risky decision-making and neural activation during decision-making among youth with ADHD/DBDs.

METHOD

Forty-six 11-12-year-olds (29.4% girls; 54.9% white; Tanner M(SD) = 2.08(1.32)) who met DSM-5 criteria for ADHD/DBD completed the Balloon Analog Risk Task (BART) during fMRI scanning. We examined effects of Tanner stage, sex, and age on risky decision-making (mean wager at which individuals stopped balloon inflation) and neural activation in the middle frontal gyrus and the ventral striatum during the choice and outcome phases of decision-making.

RESULTS

Those in earlier pubertal stages made riskier decisions during the BART compared to those in later Tanner stages (β=-0.62, p =  .02). Later pubertal stage was associated with greater activation in the left middle frontal gyrus (β=0.61, p = .03) during the choice phase and in the right ventral striatum in response to rewards (β=0.59, p = .03).

CONCLUSION

Youth with ADHD/DBD in later stages of puberty, regardless of age, show greater ventral striatal activation in response to rewards.

Determination of Pubertal Status in Youths With Type 1 Diabetes Using Height Velocity and Trajectories

CONTEXT

Assessment of pubertal change is important for the management of chronic pediatric diseases, such as type 1 diabetes. Physical and/or laboratory assessments of pubertal status are often unavailable, impractical, or costly.

OBJECTIVE

To develop and validate a practical and objective method to assess pubertal status using longitudinal linear growth in youths with type 1 diabetes.

DESIGN, PARTICIPANTS, AND OUTCOME MEASUREMENTS

Participants (n = 123) were part of a 2-year study assessing continuous glucose monitoring in youths with type 1 diabetes at a tertiary diabetes center. Pubertal status at visits was assigned by a tiered approach using clinical Tanner staging or indicators of pubertal maturation from the electronic medical record when available. For other visits, independent evaluations of height velocities and growth chart trajectories provided data for pubertal status assignments. Sensitivity analysis confirmed the validity of the pubertal status assignments.

RESULTS

The sample (50% female, 95% white) had a mean ± SD age of 12.7 ± 2.7 years, diabetes duration of 6.0 ± 3.6 years, and hemoglobin A1c of 7.9 ± 0.8%. Of 985 study visits, 50% received a pubertal status assignment based on clinical Tanner staging, 29% on additional medical record review, and 22% on an evaluation of height velocity and growth chart trajectory. For the sensitivity analysis, pubertal status assignments based on height velocity and growth chart trajectory matched clinical Tanner staging in 87% of visits.

CONCLUSIONS

Our practical and objective method to assess pubertal status based on height velocity and growth chart trajectory highlights growth as a reliable and objective bioassay for pubertal onset, status, and progression.

Associations Between Maternal Obesity and Pregnancy Hyperglycemia and Timing of Puberty Onset in Adolescent Girls: A Population-Based Study

Early puberty is associated with adverse health outcomes. We investigated whether in utero exposure to maternal obesity is associated with daughters' pubertal timing using 15,267 racially/ethnically diverse Kaiser Permanente Northern California members aged 6-11 years with pediatrician-assessed Tanner staging (2003-2017). We calculated maternal body mass index (BMI; weight (kg)/height (m)2) during pregnancy from the electronic health record data. Using a proportional hazards model with interval censoring, we examined the associations between maternal obesity and girls' pubertal timing, as well as effect modification by race/ethnicity and mediation by prepubertal BMI. Maternal obesity (BMI ≥30) and overweight (BMI 25-29.9) were associated with earlier onset of breast development in girls (hazard ratio (HR) = 1.39 (95% confidence interval (CI): 1.30, 1.49) and HR = 1.21 (95% CI: 1.13, 1.29), respectively), after adjustment for girl's race/ethnicity, maternal age, education, parity, and smoking during pregnancy. There was interaction by race/ethnicity for associations between maternal obesity and girls' pubic hair onset: Associations were strongest among Asian and non-Hispanic white girls (HR = 1.53 (95% CI: 1.24, 1.90) and HR = 1.34 (95% CI: 1.18, 1.52), respectively) and absent for African-American girls. Adjustment for girl's prepubertal BMI only slightly attenuated associations. Our results suggest the importance of maternal metabolic factors during pregnancy in the timing of girls' puberty and potential differences in the associations by race/ethnicity.

Comparison of methods to assess onset of breast development in the LEGACY Girls Study: methodological considerations for studies of breast cancer

Background

Younger age at onset of breast development, which has been declining in recent decades, is associated with increased breast cancer risk independent of age at menarche. Given the need to study the drivers of these trends, it is essential to validate methods to assess breast onset that can be used in large-scale studies when direct clinical assessment of breast onset is not feasible.

Methods

Breast development is usually measured by Tanner stages (TSs), assessed either by physical examination or by mother’s report using a picture-based Sexual Maturation Scale (SMS). As an alternative, a mother-reported Pubertal Development Scale (PDS) without pictures has been used in some studies. We compared agreement of SMS and PDS with each other (n = 1022) and the accuracy of PDS with clinical TS as a gold standard for the subset of girls with this measure (n = 282) using the LEGACY cohort. We further compared prediction of breast onset using ROC curves and tested whether adding urinary estrone 1-glucuronide (E1G) improved the AUC.

Results

The agreement of PDS with SMS was high (kappa = 0.80). The sensitivity of PDS vs clinical TS was 86.6%. The AUCs for PDS alone and SMS alone were 0.88 and 0.79, respectively. Including E1G concentrations improved the AUC for both methods (0.91 and 0.86 for PDS and SMS, respectively).

Conclusions

The PDS without pictures is a highly accurate, sensitive, and specific method for assessing breast onset, especially in settings where clinical TS is not feasible. In addition, it is comparable to SMS methods with pictures and thus easier to implement in large-scale studies, particularly phone-based interviews where pictures may not be available. Urinary E1G can improve accuracy over than PDS or SMS alone.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-0943-9) contains supplementary material, which is available to authorized users.

Breast cancer family history and allele-specific DNA methylation in the legacy girls study

Family history, a well-established risk factor for breast cancer, can have both genetic and environmental contributions. Shared environment in families as well as epigenetic changes that also may be influenced by shared genetics and environment may also explain familial clustering of cancers. Epigenetic regulation, such as DNA methylation, can change the activity of a DNA segment without a change in the sequence; environmental exposures experienced across the life course can induce such changes. However, genetic-epigenetic interactions, detected as methylation quantitative trait loci (mQTLs; a.k.a. meQTLs) and haplotype-dependent allele-specific methylation (hap-ASM), can also contribute to inter-individual differences in DNA methylation patterns. To identify differentially methylated regions (DMRs) associated with breast cancer susceptibility, we examined differences in white blood cell DNA methylation in 29 candidate genes in 426 girls (ages 6-13 years) from the LEGACY Girls Study, 239 with and 187 without a breast cancer family history (BCFH). We measured methylation by targeted massively parallel bisulfite sequencing (bis-seq) and observed BCFH DMRs in two genes: ESR1 (Δ4.9%, P = 0.003) and SEC16B (Δ3.6%, P = 0.026), each of which has been previously implicated in breast cancer susceptibility and pubertal development. These DMRs showed high inter-individual variability in methylation, suggesting the presence of mQTLs/hap-ASM. Using single nucleotide polymorphisms data in the bis-seq amplicon, we found strong hap-ASM in SEC16B (with allele specific-differences ranging from 42% to 74%). These findings suggest that differential methylation in genes relevant to breast cancer susceptibility may be present early in life, and that inherited genetic factors underlie some of these epigenetic differences.

Pubertal development in girls by breast cancer family history: the LEGACY girls cohort

Background

Pubertal milestones, such as onset of breast development and menstruation, play an important role in breast cancer etiology. It is unclear if these milestones are different in girls with a first- or second-degree breast cancer family history (BCFH).

Methods

In the LEGACY Girls Study (n = 1040), we examined whether three mother/guardian-reported pubertal milestones (having reached Tanner Stage 2 or higher (T2+) for breast and pubic hair development, and having started menstruation) differed by BCFH. We also examined whether associations between body size and race/ethnicity and pubertal milestones were modified by BCFH. We used mother/guardian reports as the primary measure of pubertal milestones, but also conducted sensitivity analyses using clinical Tanner measurements available for a subcohort (n = 204). We analyzed cross-sectional baseline data with logistic regression models for the entire cohort, and longitudinal data with Weibull survival models for the subcohort of girls that were aged 5–7 years at baseline (n = 258).

Results

BCFH was modestly, but not statistically significantly, associated with Breast T2+ (odds ratio (OR) = 1.36, 95% confidence interval (CI) = 0.88–2.10), with a stronger association seen in the subcohort of girls with clinical breast Tanner staging (OR = 2.20, 95% CI = 0.91–5.32). In a longitudinal analysis of girls who were aged 5–7 years at baseline, BCFH was associated with a 50% increased rate of having early breast development (hazard ratio (HR) = 1.49, 95% CI = 1.0–2.21). This association increased to twofold in girls who were not overweight at baseline (HR = 2.04, 95% CI = 1.29–3.21). BCFH was not associated with pubic hair development and post-menarche status. The median interval between onset of breast development and menarche was longer for BCFH+ than BCFH– girls (2.3 versus 1.7 years), suggesting a slower developmental tempo for BCFH+ girls. Associations between pubertal milestones and body size and race/ethnicity were similar in girls with or without a BCFH. For example, weight was positively associated with Breast T2+ in both girls with (OR = 1.06 per 1 kg, 95% CI = 1.03–1.10) and without (OR = 1.14 per 1 kg, 95% CI = 1.04–1.24) a BCFH.

Conclusions

These results suggest that BCFH may be related to earlier breast development and slower pubertal tempo independent of body size and race/ethnicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0849-y) contains supplementary material, which is available to authorized users.

Non-invasive optical spectroscopic monitoring of breast development during puberty

Background

Tanner staging (TS), a five-stage classification indicating no breast tissue (TS1) to full breast development (TS5), is used both in health research and clinical care to assess the onset of breast development (TS2) and duration in each stage. Currently, TS is measured both visually and through palpation but non-invasive methods will improve comparisons across settings.

Methods

We used optical spectroscopy (OS) measures from 102 girls at the Ontario site of the LEGACY girls study (average age 12 years, range 10.0–15.4 years) to determine whether breast tissue optical properties map to each TS. We further examined whether these properties differed by age, body mass index (BMI), and breast cancer risk score (BCRS) by examining the major principal components (PC).

Results

Age and BMI increased linearly with increasing TS. Eight PCs explained 99.9% of the variation in OS data. Unlike the linear increase with age and BMI, OS components had distinct patterns by TS: the onset of breast development (TS1 to TS2) was marked by elevation of PC3 scores indicating an increase in adipose tissue and decrease in signal from the pectoral muscle; transition to TS3 was marked by elevation of PC6 and PC7 and decline of PC2 scores indicating an increase in glandular or dense tissue; and transition to TS4+ by decline of PC2 scores representing a further increase in glandular tissue relative to adipose tissue. Of the eight PCs, three component scores (PC4, PC5, and PC8) remained in the best-fitting model of BCRS, suggesting different levels of collagen in the breast tissue by BCRS.

Conclusions

Our results suggest that serial measures of OS, a non-invasive assessment of breast tissue characteristics, can be used as an objective outcome that does not rely on visual inspection or palpation, for studying drivers of breast development.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0805-x) contains supplementary material, which is available to authorized users.