[Impact of maternal age distribution on the expected live birth prevalence of Down's syndrome in the metropolitan France between 1965 and 2008]

Birth Defects Data From Population-Based Birth Defects Surveillance System in a District of Southern Jiangsu, China, 2014-2018

As a population-based national surveillance region, Tianning District confronts with great challenges in birth defects (BDs) prevention. We aimed to describe the epidemiology of BDs in infants (including dead fetus, stillbirth, or live birth between 28 weeks of gestation and 42 days after birth) in Tianning District from 2014 to 2018. The data was collected from the national birth defect surveillance system. The prevalence rates of BDs were calculated by poisson distribution. Trends of incidence and the associations of regarding perinatal characteristics with BDs were analyzed by poisson regression. During the study period, the prevalence of BD was 155.49 per 10,000 infants. The ten leading BDs were congenital heart defects (CHD), polydactyly, Congenital malformation of kidney (CMK), syndactyly, cleft palate, hypospadias, Congenital hypothyroidism (CH), congenital atresia of rectum and anus, congenital talipes equinovarus (CTE), and microtia. A significant increase in the prevalence of CHD was observed with a prevalence rate ratio (PRR) of 1.191. Gravidity ≥ 3 (PRR = 1.38) and multiple births (PRR = 2.88) were risk factors for BDs. Premature delivery (PRR = 4.29), fetal death or stillbirth (PRR = 24.79), and infant death (PRR = 43.19) were adverse consequences of BDs. Strengthening publicity and education, improving the ability of diagnosis and monitoring, expanding surveillance time quantum of BDs system may be warranted.

Epidemiology of birth defects based on a birth defect surveillance system in Southern Jiangsu, China, 2014-2018

Introduction: Changzhou has been confronted with great challenges in birth defects (BDs) prevention, as the prevalence rates of BDs in Changzhou increased rapidly. The aims of this study were to describe the epidemiology of BDs in perinatal infants (PIs, including dead fetus, stillbirth, or live birth between 28 weeks of gestation and 7 days after birth) in Changzhou during the period from 2014 to 2018.Methods: The BD surveillance data of PIs were collected from 56 hospitals of Changzhou. The prevalence rate of BDs with 95% confidence interval (CI) were calculated by Poisson distribution. Univariate and multivariate Poisson regression was performed to identify the changing trends of prevalence rates of BDs by year and the association of regarding BD characteristics including year, infant gender, maternal age, and season with BDs successively.Results: From 2014 to 2018, there were a total of 238,712 PIs of which 1707 had BDs, with the average prevalence of 71.509 per 10,000 PIs, showing a remarkable uptrend (aPRR = 1.133, 95%CI: 1.094-1.173). The ten leading BDs were polydactyly, congenital heart defects (CHD), syndactyly, microtia, cleft lip and palate (CLP), hypospadias, cleft palate, other malformation of external ear (OMEE), congenital atresia of rectum and anus, and congenital talipes equinovarus (CTE). During the study period, the prevalence rates of polydactyly, CHD and syndactyly increased significantly (PRR = 1.195, 95%CI: 1.109-1.288, PRR = 1.194, 95%CI: 1.105-1.291, and PRR = 1.143, 95%CI: 1.007-1.297, respectively); the prevalence rates of congenital esophageal atresia decreased significantly (PRR = 0.571, 95%CI: 0.395-0.826). The risk of BDs was higher in male PIs versus female PIs (aPRR = 1.235, 95%CI: 1.123-1.358).Conclusions: A significant increase in the prevalence of BDs was detected from 2014 to 2018 in Changzhou. CHD, polydactyly, and syndactyly increased much and congenital esophageal atresia declined much. Male PIs was risk factor for occurrence of BDs. Collecting information on factors associated with BDs, setting the report time of BDs system at smaller gestational age so as to get an exact prevalence and make better prevention strategy, strengthening the publicity and education, improving the ability of monitoring, and wider use of new diagnosis technology are important to reduce the prevalence of BDs in PIs.

Fetopathological examination for the fetuses with Down syndrome in Tunisia: Epidemiological study and associated malformations

BACKGROUND

For Down syndrome (DS), traditional epidemiological studies to determine the prevalence, cause, and clinical significance of the syndrome have been conducted over the last 100 years. In Tunisia, the current work is the first in-depth study in epidemiology of DS from fetopathological data.

AIM OF THE STUDY

The aim of this epidemiological study was to determine the impact of some feto-maternal characteristics in occurrence of DS and to search the frequency of associated congenital malformations with this syndrome.

METHODS

Our retrospective study was realized for 144 fetuses with DS among 9321 autopsied fetuses in embryo-fetopathological service between 1994 and 2011.

RESULTS

In our study, the majority of mothers (72.91%) were 35 years and older, with a statistically significant difference (p<10^-6, OR=16.7, CI=8.7-32.4). The abnormalities of extremities (31%) were the most common fetal abnormalities followed by facial (23.51%) and digestive abnormalities (19.63%).

CONCLUSION

One of the main conclusions of this research is that the most common risk factor for DS is maternal age. On the other hand, the type and the frequency of associated congenital anomalies with DS are still controversial.

DS-Connect: A Promising Tool to Improve Lives and Engage Down Syndrome Communities Worldwide

Down syndrome (DS) is the most common genetic cause of intellectual and developmental disabilities in the United States with an estimated birth prevalence of 1:691 births; however, worldwide estimates of the number of individuals with intellectual and developmental disabilities, including DS, remain speculative. Little is known about the global health impact of DS, such as heart defects, gastrointestinal malformations, and other medical and behavioral issues. Further research is needed to develop the next generation of novel therapies and compounds aimed at improving cognition, reducing dementia, and mitigating other manifestations of DS. To address these challenges, the National Institutes of Health has created the first web-based, voluntary registry and data resource called DS-Connect: The Down Syndrome Registry to collect demographic and health information about individuals with DS.

Genetic constraints underlying human reproductive timing in a premodern Swiss village

The trade-off between reproductive investment in early versus late life is central to life-history theory. Despite abundant empirical evidence supporting different versions of this trade-off, the specific trade-off between age at first reproduction (AFR) and age at last reproduction (ALR) has received little attention, especially in long-lived species with a pronounced reproductive senescence such as humans. Using genealogical data for a 19th-century Swiss village, we (i) quantify natural selection acting on reproductive timing, (ii) estimate the underlying additive genetic (co)variances, and (iii) use these to predict evolutionary responses. Selection gradients were computed using multiple linear regression, and the additive genetic variance-covariance matrix was estimated using a restricted maximum-likelihood animal model. We found strong selection for both an early AFR and a late ALR, which resulted from selection for an earlier and longer reproductive period (RP, i.e., ALR-AFR). Furthermore, postponing AFR shortened RP in both sexes, but twice as much in women. Finally, AFR and ALR were strongly and positively genetically correlated, which led to a considerable reduction in the predicted responses to selection, or even rendered them maladaptive. These results provide evidence for strong genetic constraints underlying reproductive timing in humans, which may have contributed to the evolution of menopause.