Association Between Paternal Separation During Early Childhood and Pubertal Timing Among Girls Using Longitudinal Birth Cohort in Japan

IntroductionPrevious studies have shown that paternal absence leads to earlier pubertal timing among girls in high-income countries. Despite the low divorce rate in Japan, paternal separation is commonly seen due to a unique corporation system, tanshin funin, where employees relocate with their spouses and children. We examined paternal separation, including paternal absence (due to divorce or paternal death) and paternal tanshin funin, during early childhood as a predictor of earlier girl’s pubertal development, assessed as age at peak height velocity (PHV).MethodsThis study examined 15 214 girls from a longitudinal survey conducted in Japan from 2001 to 2016 by the Ministry of Health, Labor and Welfare. Paternal separation was determined by the occurrence through annual surveys conducted at ages 0.5 to 4.5 years. Outcome was defined as age at PHV between ages 6 to 15 years. We conducted linear regression, adjusted for potential confounders and other covariates.ResultsContinuous father cohabitation was seen in 88.7% of households, while paternal separation was experienced 1-2, 3-4 and 5 times (always) among 7.4%, 2.8% and 1.1% of households, respectively. Girls who confronted continuous paternal separation (5 times) experienced 0.42 years earlier [95% confidence interval (CI): -0.75, -0.10] age at PHV compared to their peers who always lived with their fathers.ConclusionGirls who experienced paternal separation throughout ages 0.5 to 4.5 years experienced PHV earlier.

Timing of the Pubertal Growth Spurt and Prostate Cancer

Previous studies of pubertal timing and the risk of prostate cancer have used self-reported markers of pubertal development, recalled in mid-life, and the results have been inconclusive. Our aim was to evaluate the age at the pubertal growth spurt, an objective marker of pubertal timing, and the risk of prostate cancer and high-risk prostate cancer. This population-based cohort study included 31,971 men with sufficient height measurements to calculate age at peak height velocity (PHV). Outcomes were accessed through national registers. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated by Cox regressions with follow up starting at 20 years of age. In total, 1759 cases of prostate cancer including 449 high-risk were diagnosed during follow up. Mean follow up was 42 years (standard deviation 10.0). Compared to quintiles 2–4 (Q2–4), men in the highest age at PHV quintile (Q5) had lower risk of prostate cancer (HR 0.83, 95% CI 0.73–0.94), and of high-risk prostate cancer (0.73; 0.56–0.94). In an exploratory analysis with follow up starting at age at PHV, late pubertal timing was no longer associated with reduced risk of prostate cancer. Later pubertal timing was associated with reduced risk of prostate cancer and especially high-risk prostate cancer. We propose that the risk of prostate cancer might be influenced by the number of years with exposure to adult levels of sex steroids.

Reward sensitivity and internalizing symptoms during the transition to puberty: An examination of 9-and 10-year-olds in the ABCD Study

Early pubertal timing has been linked to increased risk for internalizing disorders. Work in older adolescents and adults suggests that heightened reward sensitivity may buffer risk for internalizing symptoms, but few studies have investigated these associations during the early transition to puberty, a window of vulnerability to mental health risk. In this preregistered study, we investigated the associations among pubertal timing, internalizing symptoms, and reward sensitivity in 11,243 9-10 year-olds from the Adolescent Brain Cognitive Development (ABCD) Study®. Using split-half analysis, we tested hypothesized effects across two subsets of the sample (Sample 1 N=5,631 ; Sample 2 N=5,612). Across samples, early pubertal timing was associated with higher internalizing symptoms in females and males, with highest symptoms evident in mid-pubertal adolescents. Additionally, early pubertal timing was robustly associated with greater self-reported reward sensitivity in both females and males. We observed preliminary evidence of a moderating role of self-reported and neural reward sensitivity in the association between early pubertal timing and internalizing symptoms, but several of these effects differed by sex, and no moderation effects replicated across samples. Together, these findings provide novel insights into early indicators of risk for internalizing disorders during the transition to puberty.

Gut microbiota develop towards an adult profile in a sex-specific manner during puberty

Accumulating evidence indicates that gut microbiota may regulate sex-hormone levels in the host, with effects on reproductive health. Very little is known about the development of intestinal microbiota during puberty in humans. To assess the connection between pubertal timing and fecal microbiota, and to assess how fecal microbiota develop during puberty in comparison with adult microbiota, we utilized a Finnish allergy-prevention-trial cohort (Flora). Data collected at 13-year follow-up were compared with adult data from a different Finnish cohort. Among the 13-year-old participants we collected questionnaire information, growth data from school-health-system records and fecal samples from 148 participants. Reference adult fecal samples were received from the Health and Early Life Microbiota (HELMi) cohort (n = 840). Fecal microbiota were analyzed using 16S rRNA gene amplicon sequencing; the data were correlated with pubertal timing and compared with data on adult microbiota. Probiotic intervention in the allergy-prevention-trial cohort was considered as a confounding factor only. The main outcome was composition of the microbiota in relation to pubertal timing (time to/from peak growth velocity) in both sexes separately, and similarity to adult microbiota. In girls, fecal microbiota became more adult-like with pubertal progression (p = 0.009). No such development was observed in boys (p = 0.9). Both sexes showed a trend towards increasing relative abundance of estrogen-metabolizing Clostridia and decreasing Bacteroidia with pubertal development, but this was statistically significant in girls only (p = 0.03). In girls, pubertal timing was associated positively with exposure to cephalosporins prior to the age of 10. Our data support the hypothesis that gut microbiota, particularly members of Ruminococcaceae, may affect pubertal timing, possibly via regulating host sex-hormone levels.Trial registration The registration number for the allergy-prevention-trial cohort: ClinicalTrials.gov, NCT00298337, registered 1 March 2006—Retrospectively registered, https://clinicaltrials.gov/show/NCT00298337. The adult-comparison cohort (HELMi) is NCT03996304.

Exploring the Interaction Effects of Gender Contentedness and Pubertal Timing on Adolescent Longitudinal Psychological and Behavioral Health Outcomes

Background: Off-time pubertal timing (PT) and non-conforming gender identity have been reported to predict adverse health and well-being in adolescents. However, the joint effects of these two factors are less addressed. We aimed to investigate the main and interaction effects of gender identity, proxied by perceived gender contentedness (GC), and PT on longitudinal adolescent psychological and behavioral outcomes.Methods: Data (N = 1806, Mage = 13.3 ± 0.5 years) come from the Taiwan Youth Project, which prospectively followed a longitudinal cohort of Taiwanese junior high school students from 2000 (wave 1) to 2009 (wave 9). GC was self-reported at waves 1 and 9 in a binary response, and thus 4 GC trajectories were created. PT was defined using the Pubertal Developmental Scale, which mainly measured physical changes in puberty. Multiple linear regression analyses with gender stratification were applied to examine the effects of the GC trajectory and its interaction with PT on the outcomes.Results: A total of 1,562 subjects (86.5%) remained consistently satisfied with their gender, while the GC of 226 subjects (12.6%) changed at some point. Regression analyses found that males with gender dissatisfaction at wave 9 were likely to engage in delinquent behavior, and females in this group were more likely to have lower self-esteem, as compared to those with consistent GC. The interaction effect between the GC trajectory and PT appeared to be associated with smoking and drinking only at wave 1.Conclusions: These findings indicate that healthcare professionals should concentrate on gender non-conforming individuals at early adolescence, navigating them toward a healthy adulthood.