Placental size at 19 weeks predicts offspring bone mass at birth: findings from the Southampton Women's Survey

Ultrasound Evaluation of Placental Thickness: Insights From an Observational Study and Implications for Fetal Growth Assessment

Introduction A precise gestational age (GA) assessment is critical to monitoring fetal growth and planning delivery. Any disorder that affects the placenta will affect the fetus. Hence, the placenta serves as an indicator of fetal development. So, placental thickness (PT) measurement can be utilized as a parameter in the precise estimation of gestational age and prediction of the fetal outcome. Ultrasound (USG) remains the preferred method for detecting placental abnormalities due to its benefits. This study aimed to evaluate placental thickness by USG in various GA subgroups and to see the correlation of PT with GA and fetal outcome. Methods Cross-sectional observational study with short follow-up. A total of 296 antenatal women between 14 weeks and 40 weeks underwent USG to measure placental thickness and were followed up until delivery. The collected data was compiled systematically and analyzed using IBM SPSS Statistics for Windows, Version 25 (released 2017; IBM Corp., Armonk, New York, United States). The level of significance was taken as p<0.05. Results The mean placental thickness progressed from 1.8 cm to 3.5 cm as the gestational age advanced from 14 weeks to 35 weeks and six days. After that, it decreased until delivery (r-value = 0.531 (<0.8), p-value <0.001). PT was positively correlated only with birth weight (p-value 0.013) amongst all fetal outcome parameters. Conclusion GA can be determined using PT with the help of regression techniques. PT can be used as a replacement when a particular parameter of the composite growth formula is fallacious. The PT increase rate is a more reliable indicator than the actual PT to predict birth weight.

Maternal and Neonatal Factors Affecting Bone Mineral Content of Indonesian Term Newborns

Background: Interactions between the genome and intrauterine environment can affect bone mineralization in newborns and even in adult life. Several studies show that intrauterine fetal bone mineralization or early postnatal bone condition influences the risk of osteoporosis in later life. Objectives: To determine whole body bone mineral content (WB BMC) and factors that influence neonatal WB BMC in Indonesian term newborns. Subjects/Methods: A cross-sectional study was conducted in Dr. Sardjito General Hospital, Yogyakarta, Indonesia. A total of 45 term, appropriate for gestational age (AGA) newborns were included in this study. BMC was assessed by dual-energy x-ray absorptiometry (DXA) in the first week of life. Weight (g), length (cm) and head circumference (cm) were measured at birth. Data on maternal characteristics were obtained from the maternal health records or reported by the mothers. Results: WB BMC measured in the present study (mean ± SD: 33.2 ± 9.3 g) was lower than WB BMC of similar populations in developed countries. Multiple linear regression showed that birth weight, birth length, and gestational age had a positive association with WB BMC (p = 0.048, 0.017, and <0.001, respectively), while maternal cigarette exposure had a negative association with WB BMC (p = 0.012). Male infants had significantly higher of WB BMC than female (p = 0.025). These determinants contribute to 55% variability of WB BMC. Conclusions: WB BMC in Indonesian term newborns is lower than populations in developed countries. Birth weight, length, gestational age, sex, and maternal cigarette exposure during pregnancy are significantly associated with WB BMC observed in Indonesian newborns.

Placental volume at 11 weeks is associated with offspring bone mass at birth and in later childhood: Findings from the Southampton Women's Survey

OBJECTIVES

To investigate associations between placental volume (PV) at 11 weeks' gestation and offspring bone outcomes at birth, 6 years and 8 years.

METHODS

3D ultrasound scanning was used to assess 11 week PV in a subset (n = 236) of the Southampton Women's Survey (a prospective mother-offspring cohort). Maternal anthropometric measures and lifestyle information were obtained pre-pregnancy and at 11 weeks' gestation. Offspring dual-energy x-ray absorptiometry scanning was performed within 2 weeks postnatally and at 6 and 8 years. Linear regression was used to assess associations between PV and bone outcomes, adjusting for offspring age at DXA and sex, and maternal age, height, smoking status, walking speed and triceps skinfold thickness. β are SD change in bone outcome per SD change in PV.

RESULTS

In adjusted models, 11 week PV was positively associated with bone area (BA) at all time points, with evidence of persisting associations with increasing childhood age (birth: n = 80, β = 0.23 [95%CI = 0.03, 0.42], 6 years: n = 110, β = 0.17 [-0.01, 0.36], 8 years: n = 85, β = 0.13 [-0.09, 0.36]). Similar associations between 11 week PV and bone mineral content (BMC) were observed. Associations with size-corrected bone mineral content were weaker at birth but strengthened in later childhood (birth: n = 78, β = 0.07 [-0.21, 0.35], 6 years: n = 107, β = 0.13 [-0.08, 0.34], 8 years: n = 71, β = 0.19 [-0.05, 0.43]).

CONCLUSIONS

11 week PV is associated with DXA bone measures at birth, with evidence of persisting associations into later childhood. Further work is required to elucidate the contributions of placental morphology and function to gestational influences on skeletal development.

Perinatal biomarkers implying 'Developmental Origins of Health and Disease' consequences in intrauterine growth restriction

The intrauterine-growth-restricted (IUGR) state, particularly the asymmetric one, has been associated with 'Developmental Origins of Health and Disease' (DOHaD) consequences later in life. Several environmental factors, acting during the phase of foetal developmental plasticity interact with genotypic variation, 'programme' tissue function and change the capacity of the organism to cope with its environment. They may be responsible for chronic illness risk in adulthood. Detection of possible future DOHaD consequences at a very early age, by applying relevant biomarkers, is of utmost importance. This review focuses on biomarkers possibly predicting consequences from bone, psychoneural system and lung. Although no concrete biomarker has been identified for bone disorders in adulthood, reduced brain-derived neurotrophic factor (BDNF) concentrations in cord blood and BDNF DNA methylation might predict schizophrenia and possibly depression, bipolar disorder and autism. High surfactant protein D (SP-D) concentrations in cord blood of IUGR foetuses/neonates could point to structural lung immaturity, resulting to asthma and chronic obstructive pulmonary disease in adult life.

Bone Mass in Newborns Assessed by DXA - A Systematic Review and Meta-analysis

PURPOSE

Peak bone mass - a key determinant of osteoporotic fractures result from bone accretion starting form intrauterine life to early adulthood. Optimal skeletal growth in-utero and infancy may offer protection against osteoporosis in adult life. We attempted to pool the data from available literature to get a consensus on average bone mass among healthy newborns (age ≤30 days after birth).

METHODS

Systematic review was conducted (PRISMA guidelines) to generate pooled estimates of bone mass parameters at whole body (WB) and lumbar spine (LS), based on both fixed and random effect models of meta-analyses. Two investigators independently carried out a comprehensive literature search using PubMed, Google Scholar and Embase. Meta-regression was applied to further explore causes of heterogeneity.

RESULTS

Out of a total 2703 studies, 2682 was excluded leaving 21 studies for final analysis. Thirteen studies reported bone mass by Hologic^® and eight by Lunar^®. The pooled WBBMC was 66.2g (95% CI 65.4 to 67.05 by fixed effect model, while the corresponding parameter for LS was 2.3g (95% CI 2.2 to 2.4). The subgroup and meta-regression analyses done for controlling potential confounders did not significantly affect heterogeneity.

CONCLUSION

We generated the pooled estimate of bone mass (WBBMC) among healthy newborn subjects. There was high degree of heterogeneity among studies.

Ovine prenatal growth restriction impacts glucose metabolism and body composition throughout life in both sexes

Low birthweight is a risk factor for later adverse health. Here the impact of placentally mediated prenatal growth restriction followed by postnatal nutrient abundance on growth, glucose metabolism and body composition was assessed in both sexes at key stages from birth to mid-adult life. Singleton-bearing adolescent dams were fed control or high nutrient intakes to induce normal or growth-restricted pregnancies respectively. Restricted lambs had ~40% reduced birthweight. Fractional growth rates were higher in restricted lambs of both sexes predominantly during suckling/juvenile phases. Thereafter, rates and patterns of growth differed by sex. Absolute catch-up was not achieved and restricted offspring had modestly reduced weight and stature at mid-adulthood necropsy (~109 weeks). Dual-energy X-ray absorptiometry revealed lower bone mineral density in restricted vs normal lambs at 11, 41, 64 and 107 weeks, with males > females from 41 weeks onwards. Body fat percentage was higher in females vs males throughout, in restricted vs normal lambs at weaning (both sexes) and in restricted vs normal females at mid-adulthood. Insulin secretion after glucose challenge was greater in restricted vs normal of both sexes at 7 weeks and in restricted males at 32 weeks. In both sexes, fasting glucose concentrations were greater in restricted offspring across the life course, while glucose area under the curve after challenge was higher in restricted offspring at 32, 60, 85 and 106 weeks, indicative of persistent glucose intolerance. Therefore, prenatal growth restriction has negative consequences for body composition and metabolism throughout the life course with the effects modulated by sex differences in postnatal growth rates, fat deposition and bone mass accrual.

Sexual Dimorphism and the Origins of Human Spinal Health

Recent observations indicate that the cross-sectional area (CSA) of vertebral bodies is on average 10% smaller in healthy newborn girls than in newborn boys, a striking difference that increases during infancy and puberty and is greatest by the time of sexual and skeletal maturity. The smaller CSA of female vertebrae is associated with greater spinal flexibility and could represent the human adaptation to fetal load in bipedal posture. Unfortunately, it also imparts a mechanical disadvantage that increases stress within the vertebrae for all physical activities. This review summarizes the potential endocrine, genetic, and environmental determinants of vertebral cross-sectional growth and current knowledge of the association between the small female vertebrae and greater risk for a broad array of spinal conditions across the lifespan.

Vertebral cross-sectional area: an orphan phenotype with potential implications for female spinal health

A high priority in imaging-based research is the identification of the structural basis that confers greater risk for spinal disorders. New evidence indicates that factors related to sex influence the fetal development of the axial skeleton. Girls are born with smaller vertebral cross-sectional area compared to boys-a sexual dimorphism that is present throughout life and independent of body size. The smaller female vertebra is associated with greater flexibility of the spine that could represent the human adaptation to fetal load. It also likely contributes to the higher prevalence of spinal deformities, such as exaggerated lordosis and progressive scoliosis in adolescent girls when compared to boys, and to the greater susceptibility for spinal osteoporosis and vertebral fractures in elderly women than men.

Placental Size Is Associated Differentially With Postnatal Bone Size and Density

We investigated relationships between placental size and offspring adolescent bone indices using a population-based, mother-offspring cohort. The Avon Longitudinal Study of Parents and Children (ALSPAC) recruited pregnant women from the southwest of England between 1991 and 1993. There were 12,942 singleton babies born at term who survived at least the first 12 months. From these, 8933 placentas were preserved in formaldehyde, with maternal permission for their use in research studies. At the approximate age of 15.5 years, the children underwent a dual-energy X-ray absorptiometry (DXA) scan (measurements taken of the whole body minus head bone area [BA], bone mineral content [BMC], and areal bone mineral density [aBMD]). A peripheral quantitative computed tomography (pQCT) scan (Stratec XCT2000L; Stratec, Pforzheim, Germany) at the 50% tibial site was performed at this visit and at approximately age 17.7 years. In 2010 a sample of 1680 placentas were measured and photographed. To enable comparison of effect size across different variables, predictor and outcome variables were standardized to Z-scores and therefore results may be interpreted as partial correlation coefficients. Complete placental, DXA, and pQCT data were available for 518 children at age 15.5 years. After adjustment for gender, gestational age at birth, and age at time of pQCT, the placental area was positively associated with endosteal circumference (β [95% CI]: 0.21 [0.13, 0.30], p < 0.001), periosteal circumference (β [95% CI]: 0.19 [0.10, 0.27], p < 0.001), and cortical area (β [95% CI]: 0.10 [0.01, 0.18], p = 0.03), and was negatively associated with cortical density (β [95% CI]: -0.11 [-0.20, -0.03], p = 0.01) at age 15.5 years. Similar relationships were observed for placental volume, and after adjustment for additional maternal and offspring covariates. These results suggest that previously observed associations between placental size and offspring bone development persist into older childhood, even during puberty, and that placental size is differentially related to bone size and volumetric density. © 2016 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).

Sexual Dimorphism in Newborn Vertebrae and Its Potential Implications

OBJECTIVE

To examine whether the sex-related differences in vertebral cross-sectional area (CSA) found in children and at the timing of peak bone mass-a major determinant of osteoporosis and future fracture risk-are also present at birth.

STUDY DESIGN

Vertebral CSA, vertebral height, and intervertebral disc height were measured using magnetic resonance imaging in 70 healthy full-term newborns (35 males and 35 females). The length and CSA of the humerus, musculature, and adiposity were measured as well.

RESULTS

Weight, body length, and head and waist circumferences did not differ significantly between males and females (P ≥ .06 for all). Compared with newborn boys, girls had significantly smaller mean vertebral cross-sectional dimensions (1.47 ± 0.11 vs 1.31 ± 0.12; P < .0001). Multiple linear regression analysis identified sex as a predictor of vertebral CSA independent of gestational age, birth weight, and body length. In contrast, the sexes were monomorphic with regard to vertebral height, intervertebral disc height, and spinal length (P ≥ .11 for all). There were also no sex differences in the length or cross-sectional dimensions of the humerus or in measures of musculature and adiposity (P ≥ .10 for all).

CONCLUSION

Factors related to sex influence fetal development of the axial skeleton. The smaller vertebral CSA in females is associated with greater flexibility of the spine, which could represent the human adaptation to fetal load. Unfortunately, it also imparts a mechanical disadvantage that increases stress within the vertebrae for all physical activities and increases the susceptibility to fragility fractures later in life.

Placental vascular dysfunction, fetal and childhood growth, and cardiovascular development: the generation R study

BACKGROUND

Suboptimal fetal nutrition may influence early growth and cardiovascular development. We examined whether umbilical and uterine artery resistance indices, as measures of feto-placental and utero-placental vascular function, respectively, are associated with fetal and childhood growth and cardiovascular development.

METHODS AND RESULTS

This study was embedded in a population-based prospective cohort study among 6716 mothers and their children. Umbilical artery pulsatility index and uterine artery resistance index and fetal growth were measured in third trimester. Childhood growth was repeatedly assessed from birth to the age of 6 years. We measured body fat distribution, left ventricular mass, and blood pressure at the age of 6 years. Higher third trimester umbilical and uterine artery vascular resistance were associated with lower fetal length and weight growth in third trimester resulting in a smaller size at birth among boys and girls (P values < 0.05). These differences in length and weight growth became smaller from the age of 6 months onwards, but were still present at the age of 6 years. Higher third trimester umbilical artery vascular resistance, but not uterine artery vascular resistance, was associated with higher childhood body mass index, total fat mass, android/gynoid fat mass ratio, and systolic blood pressure, and with a lower left ventricular mass (P values<0.05). These associations were not explained by birth weight. Stronger associations tended to be present among girls as compared with boys.

CONCLUSIONS

Higher third trimester feto-placental vascular resistance, but not utero-placental vascular resistance, was associated with slower fetal growth rates and cardiovascular adaptations in childhood.