Pubertal development in girls born small for gestational age

Puberty and growth in patients with pediatric intestinal failure

BACKGROUND

Pediatric intestinal failure (PIF) affects nutrition, metabolism, and endocrine development, but its downstream impact on puberty is unknown.

METHODS

A retrospective review was performed of patients age >8 years with PIF managed at an intestinal rehabilitation program. Outcomes of interest were peak height velocity (PHV), age at PHV, and age at pubertal onset (Tanner stage 2). Outcomes were stratified by sex and compared to established norms.

RESULTS

Of 110 patients with PIF, 54.5% were male. Compared to the CDC 50th percentile, PHV in PIF patients was similar for females (8.09±2.36 vs. 7.37 cm/yr;p = 0.23) but significantly higher for males (9.27±2.56 vs. 7.91 cm/yr;p = 0.038). Age at PHV in PIF patients was significantly younger for both males (12.31±2.14 vs. 13.38 years;p = 0.049) and females (10.70±1.06 vs. 11.71 years;p = 0.001). PIF patients reached pubertal onset earlier than published norms; this was significant for males (12.41±1.80 vs. 13.44 years;p = 0.014), but not for females (10.45±1.81 vs. -11.15 years;p = 0.13). The mean height-for-age Z-score was -1.2, with 20% of patients having a Z-score less than -2.

CONCLUSIONS

Pubertal onset and growth are neither delayed nor diminished in patients with PIF. The high incidence of short stature, however, highlights the importance of optimizing prepubertal linear growth to attain full height potential.

TYPE OF STUDY

Prognosis study (Retrospective cohort study).

Early life exposure to famine and reproductive aging among Chinese women

OBJECTIVE

To assess the effect of early life exposure to famine, as endured during 1959 to 1961 in China, on reproductive aging in adult women.

METHODS

Between 2011 and 2012, 2,868 women born around the Chinese famine period (1956-1964) were enrolled in this study from three communities in China. Age at natural menopause was obtained retrospectively from a structured questionnaire. The associations of early life famine exposure with reproductive aging during adulthood were estimated, with adjustment of socioeconomic status, lifestyle factors, and body mass index.

RESULTS

Women exposed to prenatal famine had a higher risk of early menopause (ie, natural menopause <45 years, odds ratio: 1.59, 95% confidence interval [CI]: 1.07, 2.36), and a nonsignificant trend of higher risk of premature ovarian failure (ie, natural menopause <40 y, odds ratio: 1.94, 95% CI: 0.93, 4.00), compared to unexposed women. Exposure to famine during childhood was not significantly associated with reproductive aging. In a secondary analysis focusing on the fetal exposure, prenatal famine exposure was associated with a higher risk of premature ovarian failure (odds ratio: 2.07, 95% CI: 1.08, 3.87), and a nonsignificant trend of higher risk of early menopause (odds ratio: 1.37, 95% CI: 0.98, 1.91), compared to those unexposed to prenatal famine.

CONCLUSIONS

Our study showed that fetal exposure to famine was associated with an increased risk of early menopause. Such findings provided evidence in favor of the thrifty phenotype theory in reproductive aging and helped better understand the etiology of early menopause.

Relationship between final adult height and birth weight after gonadotropin-releasing hormone agonist treatment in girls with central precocious puberty

PURPOSE

The clinical significance of birth weight relative to gestational age in girls with central precocious puberty is unclear. This study sought to compare clinical parameters such as final adult height (FAH) and menarche onset after treatment with gonadotropin-releasing hormone agonist (GnRHa) on birth weight in girls with central precocious puberty treated.

METHODS

This retrospective study reviewed data of 69 girls with precocious puberty who had reached their FAH in a long-term trial of GnRHa treatment between January 2007 and December 2017. The subjects were divided into small for gestational age (SGA) (n=19) and appropriate for gestational age (AGA) (n=50) groups.

RESULTS

When starting GnRHa treatment, bone age was 10.9±0.9 and 10.3±0.8 years in the SGA and AGA groups, respectively (P&lt;0.05). The predicted adult height (PAH) (established according to the Bayley-Pinneau average table) and advanced PAH (established according to the Bayley-Pinneau advanced table) were 151.5±4.8 cm and 155.8±4.9 cm in the SGA group, respectively, and 153.4±5.3 cm and 159.0±6.0 cm in the AGA group. After treatment, no significant difference in bone age was found between the groups. The time to menarche after treatment was 12.5±7.6 and 21.1±12.3 months in the SGA and AGA groups, respectively (P&lt;0.05). FAH in the SGA and AGA groups was 161.0±4.7 cm and 161.6±5.0 cm, respectively, without a significant difference.

CONCLUSION

SGA girls with precocious puberty have increased bone age and earlier menarche relative to AGA girls. However, no difference in FAH after treatment was found between these groups.

Association between Small Fetuses and Puberty Timing: A Systematic Review and Meta-Analysis

Background: Epidemiological studies reporting the effect of small fetuses (SF) on puberty development have shown inconsistent results. Objective: To examine current study evidence and determine the strength and direction of the association between SF and puberty timing. Methods: PubMed, OVID, Web of Science, EBSCO, and four Chinese databases were searched from their date of inception to February 2016. All cohort studies that examined the association between SF and puberty timing in children were identified. Two reviewers independently screened the studies, assessed the quality of included studies, and extracted the data. The quality of the included cohort studies was assessed by the Newcastle-Ottawa Scale. Risk ratio (RR), Weighted Mean Difference (WMD), and 95% confidence intervals (CIs) were calculated and pooled by RevMan5.3 (Cochrane Collaboration, London, UK). Results: A total of 10 cohort studies involving 2366 subjects was included in the final analysis. The pooled estimates showed that SF did not significantly increase the number of pubertal children in boys (RR: 0.97; 95% CI: 0.82 to 1.15), or in girls (RR: 0.91; 95% CI: 0.79 to 1.04). Compared with the control group, the SF group had an earlier onset of puberty in girls (WMD: -0.64; 95% CI: -1.21 to -0.06), and in precocious pubarche (PP) girls (WMD: -0.10; 95% CI: -0.13 to -0.07). There was no difference in the onset of puberty in boys (WMD: -0.48; 95% CI: -1.45 to 0.50) between SF and control groups. The pooled result indicated an earlier age at menarche in girls born small for gestational age (WMD: -0.30; 95% CI: -0.58 to -0.03), but no difference in the age at menarche in the SF group of PP girls. Conclusions: SF may be associated with an earlier age of onset of puberty, especially among girls, as well as earlier age at menarche for girls. Well-designed studies with larger sample sizes and long-term follow-up among different countries and ethnicities are needed.

Puberty in children born small for gestational age

Small for gestational age (SGA) children are more prone to have precocious pubarche and exaggerated precocious adrenarche, an earlier onset of pubertal development and menarche, and faster progression of puberty than children born of appropriate for gestational age (AGA) size. The majority of studies investigating the onset of puberty in children born SGA and AGA established that, although puberty begins at an appropriate time (based on chronological age and actual height) in SGA children, onset is earlier relative to AGA children. Evaluating pubertal growth in SGA children, a more modest bone age delay from chronological age at the onset of puberty and more rapid bone maturation during puberty compared to AGA children were reported. Peak height velocity in adolescence is reached at an earlier pubertal stage and lasts for a shorter period in children born SGA than in those born AGA. These differences lead to an earlier fusion of the growth plates and a shorter adult height. The pathophysiological mechanism underlying the unique pubertal growth pattern of children born SGA remains unclear. However, it seems that this is not only related to birth weight, gestational age, adiposity or obesity, but that there may also be an influence of rapid weight gain in early childhood on pubertal onset: excess weight gain in childhood may be related to central adiposity, decreased insulin sensitivity, and increased IGF-I levels and might thus predispose to precocious pubarche.

The role of early life nutrition in programming of reproductive function

Accumulating evidence suggest that the concept of programming can also be applied to reproductive development and function, representing an ever expanding research area. Recently issues such as peri- or even preconceptional nutrition, transgenerational effects and underlying mechanisms have received considerable attention. The present chapter presents the existed evidence and reviews the available data from numerous animal and human studies on the effects of early life nutritional environment on adult reproductive function. Specific outcomes depend on the severity, duration and stage of development when nutritional perturbations are imposed, while sex-specific effects are also manifested. Apart from undernutrition, effects of relative overnutrition as well as the complex interactions between pre- and postnatal nutrition is of high importance, especially in the context of our days obesity epidemic. Mechanisms underlying reproductive programming are yet unclear, but may include a role for epigenetic modifications. Epigenetic modulation of critical genes involved in the control of reproductive function and potential intergenerational effects represent an exciting area of interdisciplinary research toward the development of new nutritional approaches during pre- and postnatal periods to ensure reproductive health in later life.

Social, behavioral, and genetic linkages from adolescence into adulthood

The influence of genetic factors on health and behavior is conditioned by social, cultural, institutional, and physical environments in which individuals live, work, and play. We encourage studies supporting multilevel integrative approaches to understanding these contributions to health, and describe the Add Health study as an exemplar. Add Health is a large sample of US adolescents in grades 7 to 12 in 1994-1995 followed into adulthood with 4 in-home interviews and biomarker collections, including DNA. In addition to sampling multiple environments and measuring diverse social and health behavior, Add Health features a fully articulated behavioral genetic sample (3000 pairs) and ongoing genotyping of 12,000 archived samples. We illustrate approaches to understanding health through investigation of the interplay among biological, psychosocial, and physical, contextual, or cultural experiences.

Long-term consequences of non-optimal birth characteristics

PROBLEM

The intrauterine milieu, gestational length as well as size at birth have a profound impact on the individual's mental, physical health and development both in childhood as well as in adult life.

METHOD OF STUDY

This paper reviews the associations between preterm birth and restricted fetal growth with neuro-developmental sequelae, including increased symptoms of psychiatric disorder in childhood and early adulthood. There is also evidence that physical morbidity such as the metabolic syndrome is more common in adult life. In addition, preterm birth and restricted fetal growth have been shown to be related to respiratory disease, infectious disease, and even malignancy. Morbidity, mental and physical as well as personality/intellectual traits hugely impact on family planning and reproductive performance in adults. As restricted fetal growth may alter organ structure and functions, it is likely to also influence subsequent fertility and/or reproductive health.

RESULTS

Individuals with non-optimal birth characteristics appears to have a reduction in childbearing and a deviant reproduction pattern compared to controls.

CONCLUSION

Future studies with sophisticated models for measuring the most vulnerable period of birth for children who have a low birth weight or who are at risk for being born preterm are needed to be able to explore the underlying biological mechanisms and also to plan for prevention as well as for interventions during pregnancy.

[Follow-up of the small-for-gestational-age child: clinical guidelines]

INTRODUCTION

In this document the Small for Gestational Age (SGA) Child Working Group of the Spanish Society for Paediatric Endocrinology proposes the guidelines for the management and follow-up of SGA children, highlighting the potential morbidity arising from the SGA condition and its consequences in adulthood.

MATERIAL AND METHODS

There is currently a wide variability in the management of the SGA child between health centres and health professionals. The diagnostic criteria for SGA according to the last international consensus guidelines are defined, which also include preterm SGA patients but excluding those patients in whom low birthweigh is associated with specific syndromes. We also outline the potential abnormalities associated with the SGA condition and recommend specific therapeutic and preventative measures.

CONCLUSIONS

Low birth weight remains a major cause of morbidity in childhood and is associated with an increased risk of health problems later in life. Childhood is a critical window during which some of the risk factors accounting for this sequence are potentially reversible, with healthy lifestyle measures and environmental intervention. Accordingly, these guidelines should be useful not only for Primary Care Paediatricians but also for Neonatologists, Paediatric Endocrinologists, Neuropaediatricians and Pediatric Gastroenterologists, and also for the parents.

Pubertal development and sexuality in female adolescents born preterm: a review of the literature

INTRODUCTION

Premature infants, especially very low birth weight infants, and fetal growth restriction are a challenge for healthcare professionals alike owing to the consequences of these conditions.

OBJECTIVE

To provide information for gynecologists, pediatricians and neonatologists to identify correct outcome expectations to help them plan their preventive and therapeutic actions. Searches were made on the MEDLINE database.

RESULTS

According to several follow-up studies, there is an increasing evidence for a link between early life exposures (prenatal and postnatal) and long-term outcomes. An adverse in utero environment will induce fetal reprogramming of neuroendocrine axes with permanent alterations of the physiology and metabolism of various body structures and functioning of neuroendocrine axes in later life, leading to a variety of different conditions, such as persistence of neurodevelopmental disability, changes in growth pattern, in body metabolism, in pubertal development, lower educational achievement and even psychological disturbances with possible alterations of sexual behavior in female adolescents and young adults. In addition, short-term transitory consequences can be also present, such as anomalies in genital appearance.

CONCLUSIONS

Outcome studies on the impact that prematurity, low birth weight and intrauterine growth restriction have on pubertal development, sexuality and fertility are still scarce. Long-term outcomes of small for gestational age or preterm adolescents are complex and multifactorial, with interactions between genetic and environmental influences involving different pathways of adaptive responses during crucial phases of prenatal growth.