High Prepubertal Leptin Levels Are Associated With Earlier Menarcheal Age

Plasma Insulin Concentration in Newborns and Children and Age at Menarche

OBJECTIVE

To investigate the association of plasma insulin levels and their trajectories from birth to childhood with the timing of menarche.

RESEARCH DESIGN AND METHODS

This prospective study included 458 girls recruited at birth between 1998 and 2011 and followed prospectively at the Boston Medical Center. Plasma nonfasting insulin concentrations were measured at two time points: at birth (cord blood) and in childhood (age 0.5-5 years). Age at menarche was obtained from a pubertal developmental questionnaire or abstracted from electronic medical records.

RESULTS

Three hundred six (67%) of the girls had reached menarche. The median (range) age at menarche was 12.4 (9-15) years. Elevated plasma insulin concentrations at birth (n = 391) and in childhood (n = 335) were each associated with an earlier mean age at menarche: approximately 2 months earlier per doubling of insulin concentration (mean shift, -1.95 months, 95% CI, -0.33 to -3.53, and -2.07 months, 95% CI, -0.48 to -3.65, respectively). Girls with overweight or obesity in addition to elevated insulin attained menarche about 11-17 months earlier, on average, than those with normal weight and low insulin. Considering longitudinal trajectories (n = 268), having high insulin levels both at birth and in childhood was associated with a roughly 6 months earlier mean age at menarche (mean shift, -6.25 months, 95% CI, -0.38 to -11.88), compared with having consistently low insulin levels at both time points.

CONCLUSIONS

Our data showed that elevated insulin concentrations in early life, especially in conjunction with overweight or obesity, contribute to the earlier onset of menarche, suggesting the need for early screening and intervention.

Leptin, ghrelin, nesfatin-1, and orexin-A plasma levels in girls with premature thelarche

PURPOSE

Reducing the mean age of puberty onset in recent years has crucial public health, clinical, and social implications. This study aimed to evaluate the serum levels of appetite-related peptides (leptin, ghrelin, nesfatin-1, and orexin-A) and anthropometric data in girls with premature thelarche (PT).

METHODS

We enrolled 44 girls aged 4-8 years diagnosed with PT and 33 age-matched healthy girls as controls. The demographic data of the girls were obtained using a questionnaire. Anthropometric data were measured and fasting blood samples were collected.

RESULTS

Body weight, height, body mass index (BMI), body fat mass, and basal metabolic rate (BMR) were higher in the PT group than in the control group (p < 0.05). Serum leptin (p < 0.001), nesfatin-1 (p = 0.001), and orxein-A (p < 0.001) levels were significantly higher in the PT group than in healthy controls. However, there were no significant differences in the serum ghrelin levels between the groups (p > 0.05). The results of multivariate logistic regression revealed that serum leptin level (OR (95% CI): 42.0 (10.91, 173.06), p < 0.001), orexin-A (OR (95% CI): 1.14 (1.04, 1.24), p = 0.006), and BMI for age z-score (OR (95% CI): 6.97 (1.47, 33.4), p = 0.014) elevated the risk of incidence of PT at 4-8 girls.

CONCLUSION

These results suggest that in addition to serum leptin levels, serum orexin-A and nesaftin-1 can take part in the initiation of PT. Few studies have investigated the relationship between nesfatin-1 and orexin-A levels and age at onset of puberty; hence, it should be a subject for future studies.

Menstrual cycle among adolescents: girls' awareness and influence of age at menarche and overweight

OBJECTIVE

To characterize the menstrual cycle (regularity and menstrual flow length), the prevalence of dysmenorrhea and self-monitoring of the cycle in students from Lisbon region, and explore the effect of chronological age, age at menarche and body mass index (BMI) on menstrual disorders.

METHODS

This is a cross-sectional study with 848 girls aged 12-18 years. A questionnaire about the sociodemographic context and characteristics of the menstrual cycle, and weight and height measures were assessed. BMI was classified according to International Obesity Taskforce criteria. A descriptive analysis of the variables was made, and Odds Ratios (ORs) and 95% confidence intervals (95%CIs) were determined.

RESULTS

Mean age at menarche was 12.4 years and mean BMI was 22.0kg/m2. Among adolescents, 59% have regular menstrual cycle, 83% have menstrual flow length of ≤6 days. 88% suffered from dysmenorrhea, among which 8,7% declare absenteeism from school and 49% took pain medication, and 65% self-monitor their menstrual cycle. Higher maternal education was associated with a higher self-monitoring of menstrual cycle among the sample (OR 1.60; 95%CI 1.15-2.17). Girls with menarche <12 years-of-age are more likely to have menstrual flow length of >6 days (OR 1.73; 95%CI 1.19-2.51) and dysmenorrhea (OR 1.87; 95%CI 1.11-3.16) than those with menarche ≥12 years-of-age. No significant association between BMI and menstrual cycle variables was observed.

CONCLUSIONS

The results suggest that menstrual disorders are frequent and may be associated with early menarche, but not with BMI. It is important to encourage self-monitoring of the menstrual cycle to detect menstrual disorders timely and promote health and well-being.

Trend of Menarcheal Age among Korean Girls

BACKGROUND

Menarcheal age has been decreasing worldwide. However, few recent studies have observed trends in menarcheal age in larger populations, and the cutoff age for early menarche remains unclear. Therefore, we aimed to analyze recent trends of menarcheal age and to determine the cutoff age of early menarche based on nationally representative data.

METHODS

We conducted a cross-sectional study of 351,006 Korean girls aged 12-18 years who were born in 1988-2003 based on the data of the 2006-2015 Korea Youth Risk Behavior Survey. We identified the distribution of age at menarche using the complex sample Cox regression model. Trends in the prevalence of early menarche were determined using the complex sample linear model.

RESULTS

Ninety-five percent of all the participants reported they had experienced menarche. The mean menarcheal age was 13.0 years (95% confidence intervals [CIs], 12.92-13.04) for girls born in 1988 and decreased to 12.6 years (95% CI, 12.54-12.61) for girls born in 2003. The cutoff age (the 3rd percentile value) for early menarche was 10.5 years during the study period. The prevalence of early menarche significantly increased from 1.8% in 2006 to 3.2% in 2015 (P-for-trend < 0.001). Downward trends of menarcheal age were noted across all body mass index groups, and this trend was most prominent in the obese group.

CONCLUSION

We reported an ongoing downward trend in menarcheal age in Korean girls born in 1988-2003, decreasing by 0.4 years over the 15 years.

Prevalência de sobrepeso e obesidade e fatores associados em mulheres de São Leopoldo, Rio Grande do Sul: um estudo de base populacional

Resumo Introdução O sobrepeso e a obesidade são multicausais, porém seus determinantes ainda não foram completamente estudados. Objetivo Estimar a prevalência de sobrepeso e de obesidade e os fatores associados. Método Estudo transversal de base populacional com 981 mulheres (20 a 60 anos) de São Leopoldo/RS. O peso e a altura foram aferidos para o cálculo do Índice de Massa Corporal (IMC). Mulheres com IMC entre 25,0 e 29,9 kg/m2 e IMC ≥ 30,0 kg/m2 foram classificadas com sobrepeso e obesidade, respectivamente. As razões de prevalência e os intervalos de confiança de 95% foram estimados por meio de regressão de Poisson. Resultados A prevalência de sobrepeso foi de 33% (IC95%: 30,1-36,0) e de obesidade foi de 31,2% (IC95%: 28,3-34,1). Após ajuste, maiores probabilidades de sobrepeso ocorreram em mulheres mais velhas, pertencentes às classes econômicas mais baixas, casadas ou em união, com histórico de obesidade materna e com uma ou mais gestações. As maiores probabilidades de obesidade ocorreram em mulheres mais velhas, de baixa renda, com histórico de obesidade materna e paterna e com três ou quatro gestações. Menarca acima de 12 anos e prática de atividade física de lazer foram fatores de proteção para a obesidade. Conclusão Esses resultados evidenciam a necessidade de ações de prevenção de longo prazo, algumas delas envolvendo ações transgeracionais.

Early maturity, shortened stature, and hardship: Can life-history trade-offs indicate social stratification and income inequality in the United States?

OBJECTIVE

Life-history strategies promote reproductive fitness and survival. Limited energy availability and competing energetic demands between life-history decisions may result in organismal trade-offs leading to selection for "optimal" traits that facilitate fitness and survival in present environmental conditions. Few life-history analyses have been conducted in food abundant/high resource human populations. Here, we use a life-history theory framework integrated with a biocultural approach to assess whether trade-offs between growth (height) and the onset of reproductive maturation (ages at menarche) were observed in a sample of adult women living in the United States.

METHODS

Adult women (18 years and older) from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2006 were analyzed using complex survey regression to evaluate associations between ages at menarche, height, and biological, socio-economic, demographic, and anthropometric variables. Associations between stature, ages at menarche, and socio-economic status (household income and education level) suggest life-history trade-offs in this populations may be mitigated by access to resources and marginalization.

CONCLUSIONS

These study results have applied public health implications. We demonstrate that females who experience early menarche in the US population achieve short stature. Our study also demonstrates the need for implementing life-history analyses in Western affluent populations, where marginalization may result in life-history trade-offs.

The Role of Growth Hormone on Ovarian Functioning and Ovarian Angiogenesis

Although not yet well-understood, today it is clear that Growth Hormone (GH) exerts a relevant role in the regulation of ovulation and fertility; in fact, fertility is lower in women with GH deficiency (GHD), and GH receptors (GHR) and GH mRNA have been found in the ovary since the onset of follicular development in humans. However, despite the strong evidence of GH in the regulation of fertility, many aspects of GH actions at this level are still not well-established, and it is likely that some controversial data depend on the species analyzed, the dose of the hormone and the duration of use of GH. Folliculogenesis, ovulation, and corpus luteum formation and maintenance are processes that are critically dependent on angiogenesis. In the ovary, new blood vessel formation facilitates oxygen, nutrients, and hormone substrate delivery, and also secures transfer of different hormones to targeted cells. Some growth factors and hormones overlap their actions in order to control the angiogenic process for fertility. However, we still know very little about the factors that play a critical role in the vascular changes that occur during folliculogenesis or luteal regression. To promote and maintain the production of VEGF-A in granulosa cells, the effects of local factors such as IGF-I and steroids are needed; that VEGF-A-inducing effect cannot be induced by luteinizing hormone (LH) or chorionic gonadotropin (CG) alone. As a result of the influences that GH exerts on the hypothalamic-pituitary-gonadal axis, facilitating the release of gonadotropins, and given the relationship between GH and local ovarian factors such as VEGF-A, FGF-2, IGF-1, or production of sex steroids, we assume that GH has to be a necessary factor in ovarian angiogenesis, as it happens in other vascular beds. In this review we will discuss the actions of GH in the ovary, most of them likely due to the local production of the hormone and its mediators.

Programmed for sex: Nutrition–reproduction relationships from an inter-generational perspective

Reproduction is our biological reason for being. Our physiology has been shaped via countless millennia of evolution with this one purpose in mind, so that at birth we are ‘programmed for sex’, although this will not kick-start functionally until puberty. Our development from an early embryo is focused on making us fit to reproduce and is intimately connected to nutrition and energy stores. Fluctuations in food supply has probably been a key evolutionary shaper of the reproductive process, and this review hypothesizes that we have developed rapid, non-genomic adaptive mechanisms to such fluctuations to better fit offspring to their perceived (nutritional) environment, thus giving them a reproductive advantage. There is abundant evidence for this notion from ‘fetal programming’ studies and from experimental ‘inter-generational’ studies involving manipulation of parental (especially paternal) diet and then examining metabolic changes in resulting offspring. It is argued that the epigenetic reprogramming of germ cells that occurs during fetal life, after fertilisation and during gametogenesis provides opportunities for sensing of the (nutritional) environment so as to affect adaptive epigenetic changes to alter offspring metabolic function. In this regard, there may be adverse effects of a modern Western diet, perhaps because it is deficient in plant-derived factors that are proven to be capable of altering the epigenome, folate being a prime example; we have evolved in tune with such factors. Therefore, parental and even grandparental diets may have consequences for health of future generations, but how important this might be and the precise epigenetic mechanisms involved are unknown.

Menstrual irregularity and use of oral contraceptives in female adolescent athletes in Swedish National Sports High Schools

Objective Female adolescent athletes seem to use oral contraceptives (OCs) in the same proportion as the general population. In athletes not using OCs, menstrual irregularity (MI) is reported to be common but there are few studies of MI in adolescent athletes. The aim of the study was to survey menarche, menstrual irregularity and use of OCs in adolescent athletes in the National Sports High Schools in Sweden. A further aim was to study the associations between current sport injury and menstrual irregularity as well as use of OCs. Subjects Two hundred and ninety-eight female adolescent athletes at Swedish National Sports High Schools. Methods A web-based questionnaire containing questions related to menstrual status, contraception and current injury. Results One third (32.6%) of the athletes used OCs and of the remaining athletes 31.8% had MI. The group of athletes with MI had a significantly (p = 0.038; Cohen's d, 0.32) lower BMI and consisted of a significantly (p = 0.043) higher proportion of endurance athletes. OC users were less likely to participate in endurance sports compared to non-OC users (p = 0.024). Current injury was equally distributed in the OC and the non-OC group but athletes with MI had fewer sports injuries compared to eumenorrheic women. Conclusion OCs are frequently used among athletes at Swedish National Sports High Schools. OC users were less likely to participate in endurance sports compared to non-OC users. MI was common and athletes with MI had lower BMI compared to eumenorrheic athletes. Sports injuries were not associated with use of OC and eumenorrheic athletes had a higher proportion of current injury.