Seasonality of congenital anomalies in Europe

Health outcomes of 1000 children born to mothers with inflammatory bowel disease in their first 5 years of life

OBJECTIVE

The aim of this study was to describe the long-term health outcomes of children born to mothers with inflammatory bowel disease (IBD) and to assess the impact of maternal IBD medication use on these outcomes.

DESIGN

We performed a multicentre retrospective study in The Netherlands. Women with IBD who gave birth between 1999 and 2018 were enrolled from 20 participating hospitals. Information regarding disease characteristics, medication use, lifestyle, pregnancy outcomes and long-term health outcomes of children was retrieved from mothers and medical charts. After consent of both parents, outcomes until 5 years were also collected from general practitioners. Our primary aim was to assess infection rate and our secondary aims were to assess adverse reactions to vaccinations, growth, autoimmune diseases and malignancies.

RESULTS

We included 1000 children born to 626 mothers (381 (61%) Crohn's disease, 225 (36%) ulcerative colitis and 20 (3%) IBD unclassified). In total, 196 (20%) had intrauterine exposure to anti-tumour necrosis factor-α (anti-TNF-α) (60 with concomitant thiopurine) and 240 (24%) were exposed to thiopurine monotherapy. The 564 children (56%) not exposed to anti-TNF-α and/or thiopurine served as control group. There was no association between adverse long-term health outcomes and in utero exposure to IBD treatment. We did find an increased rate of intrahepatic cholestasis of pregnancy (ICP) in case thiopurine was used during the pregnancy without affecting birth outcomes and long-term health outcomes of children. All outcomes correspond with the general age-adjusted population.

CONCLUSION

In our study, we found no association between in utero exposure to anti-TNF-α and/or thiopurine and the long-term outcomes antibiotic-treated infections, severe infections needing hospital admission, adverse reactions to vaccinations, growth failure, autoimmune diseases and malignancies.

A Comprehensive Assessment of the Associations Between Season of Conception and Birth Defects, Texas, 1999-2015

Birth defects prevalence may vary seasonally, but previous studies have focused on a few commonly occurring phenotypes. We performed a phenome-wide association study (PheWAS) in order to evaluate the associations between season of conception and a broad range of birth defects. Date of conception was estimated for all livebirths and birth defect cases in Texas from 1999-2015 using data from vital records, provided by the Texas Department of State Health Services Center for Health Statistics. Birth defects diagnoses were obtained from the Texas Birth Defects Registry, a statewide, active surveillance system. We estimated prevalence ratios (PRs) for phenotypes with ≥50 cases according to conception in spring (March-May), summer (June-August) or fall (September-November) relative to winter (December-February), using Poisson regression. Season of conception was associated with 5% of birth defects studied in models adjusted for maternal age, education, race/ethnicity, and number of previous livebirths. Specifically, summer conception was associated with any monitored birth defect (PR 1.03, 95% CI 1.02-1.04) and five specific phenotypes, most notably Hirschsprung disease (PR 1.46, 95% CI 1.22-1.75). These findings suggest that seasonally variable exposures influence the development of several birth defects and may assist in identifying novel environmental risk factors.

Stavudine exposure results in developmental abnormalities by causing DNA damage, inhibiting cell proliferation and inducing apoptosis in mouse embryos

Stavudine is an anti-AIDS drug widely used to prevent HIV transmission from pregnant mothers to the fetuses in underdeveloped countries for its low price. However, there is still a controversy on whether stavudine affects embryo development. In the current study, embryotoxicity of stavudine was evaluated using cultured mouse embryos with the concentrations: 5, 10, 15 μM and vehicle control. The data indicated that the effect of stavudine was dose-dependent at early neurogenesis. Stavudine exposure reduced somite numbers, yolk sac diameter, crown-rump length, and increased the rate of embryonic degeneration compared with the control. We chose the lowest but clearly toxic concentration: 5 μM to investigate the molecular mechanisms of the damage. At the molecular level, stavudine produced DNA damage, increased the levels of the phospho-CHK1 and cleaved-caspase-3, and decreased the expression level of proliferating cell nuclear antigen. These changes indicated that stavudine caused a coordinated DNA damage response, inhibited cell proliferation, and induced apoptosis in the embryos. Collectively these results suggest that stavudine exposure disturbs the embryonic development, and its use in pregnant mothers should be re-examined.

Analysis of the Seasonal Trend of Congenital Heart Defects

OBJECTIVE

To determine the seasonal trend of congenital heart defects (CHDs) in China using hospital-based clinical data.

STUDY DESIGN

We included 40 501 patients with CHD hospitalized at the Shanghai Children Medical Center between 2006 and 2017. The birth rate of CHD in each month was adjusted by sex, year of birth, and monthly birth rate of the general population. Negative binomial regression models were used to assess the seasonal trend of CHD.

RESULTS

The included patients consisted of 22 600 boys (55.8%), resulting in a male-to-female ratio of 1.26:1. Among subtypes of CHDs, ventricular septal defects and atrial septal defects were the most common, accounting for 39.7% and 12.6%, respectively. A statistically significant seasonal trend in the monthly birth rate of patients with CHDs was found; the highest relative rate of CHD was found in October and the lowest in April. After adjusting for the potential confounders, the highest relative rate of CHD was found in October and the lowest in November.

CONCLUSIONS

There seems to be a significant monthly birth rate variation of CHDs in China. The highest relative rate of CHDs occurred in October, suggesting possible maternal exposure to environmental hazards from January to March. These hazards may include air pollution, virus infection, and unhealthy lifestyle behaviors during the Spring Festival.

First Trimester Influenza Vaccination and Risks for Major Structural Birth Defects in Offspring

OBJECTIVE

To examine risks for major structural birth defects in infants after first trimester inactivated influenza vaccine (IIV) exposures.

STUDY DESIGN

In this observational study, we used electronic health data from 7 Vaccine Safety Datalink sites to examine risks for selected major structural defects in infants after maternal IIV exposure. Vaccine exposures for women with continuous insurance enrollment through pregnancy who delivered singleton live births between 2004 and 2013 were identified from standardized files. Infants with continuous insurance enrollment were followed to 1 year of age. We excluded mother-infant pairs with other exposures that potentially increased their background risk for birth defects. Selected cardiac, orofacial or respiratory, neurologic, ophthalmologic or otologic, gastrointestinal, genitourinary and muscular or limb defects were identified from diagnostic codes in infant medical records using validated algorithms. Propensity score adjusted generalized estimating equations were used to estimate prevalence ratios (PRs).

RESULTS

We identified 52 856 infants with maternal first trimester IIV exposure and 373 088 infants whose mothers were unexposed to IIV during first trimester. Prevalence (per 100 live births) for selected major structural birth defects was 1.6 among first trimester IIV exposed versus 1.5 among unexposed mothers. The adjusted PR was 1.02 (95% CI 0.94-1.10). Organ system-specific PRs were similar to the overall PR.

CONCLUSION

First trimester maternal IIV exposure was not associated with an increased risk for selected major structural birth defects in this large cohort of singleton live births.

Use of Thiopurines During Conception and Pregnancy Is Not Associated With Adverse Pregnancy Outcomes or Health of Infants at One Year in a Prospective Study

BACKGROUND & AIMS

Most data on the safety of thiopurine therapy for inflammatory bowel disease (IBD) during pregnancy come from retrospective studies, which makes it difficult to adjust for confounding factors. We performed a prospective cohort study to determine whether thiopurine use affects pregnancy outcomes or health outcomes of children.

METHODS

We performed a prospective study of all women who visited the IBD preconception outpatient clinic at our tertiary health center in The Netherlands from December 2008 through May 2016. Patients were counseled before pregnancy and seen bimonthly during pregnancy. We collected and analyzed data on medication use, as well as lifestyle and clinical factors, during conception and pregnancy. Pregnancy outcomes (live birth, spontaneous abortion, elective abortion, and stillbirth), birth outcomes (gestational age, birth weight, and congenital abnormalities), and health outcomes of infants 1 year after birth were compared between women who did and did not use a thiopurine during conception and pregnancy. In addition, health outcomes of infants 1 year after birth were compared with infants born to mothers without IBD from the same geographic region.

RESULTS

Our study comprised 309 women with confirmed IBD (216 with Crohn's disease, 85 with ulcerative colitis, and 8 with IBD unclassified). During the study period, 311 pregnancies of 232 women resulted in a live birth; a thiopurine was used during 108 pregnancies (35%). After correction for diagnosis, fertility treatment, and disease activity, there was no association between thiopurine use and spontaneous abortions. Birth outcomes were similar between women who did and did not use a thiopurine. Among infants 1 year of age, there were no differences in median growth, number of infections, allergies, adverse reactions to vaccinations, or chronic diseases between those born to women who did and did not use a thiopurine or between women with and without IBD.

CONCLUSIONS

In this prospective cohort study, we found no association between maternal thiopurine use during pregnancy and increased spontaneous abortions, adverse birth outcomes, or adverse health outcomes of infants 1 year after birth.

Seasonality, Epidemiology and Outcome of Congenital Diaphragmatic Hernia in South West of Iran

INTRODUCTION

The pathogenesis of congenital diaphragmatic hernia (CDH) is not clear. Risk factors including environmental factors have been implicated in the pathogenesis of few congenital anomalies. We aimed to assess the effect of season on the incidence of CDH and mortality rate in the southwest of Iran.

MATERIAL AND METHODS

In this retrospective study, the records of 60 patients with CDH who were admitted at Neonatal Intensive Care Unit (NICU) of Imam Khomeini Hospital of Ahvaz, Iran were evaluated.

RESULTS

Assuming that all the neonates born with CDH in the region reach this hospital, overall CDH prevalence rate was 1.09 per 10 000 total births. Conceptions in spring and summer in this region had statistically significantly higher incidence of CDH. Survival rate in the series was 41.6%.

CONCLUSION

Seasonal variation has impact on the incidence of CDH. Mortality rate in neonates with CDH is still very high.

The annual carnival in Guadeloupe (French West Indies) is associated with an increase in the number of conceptions and subsequent births nine months later: 2000 - 2011

The seasonal patterns of conceptions and births differ between geographic areas. Several potential determinants of this variation have been identified, including biological, environmental and behavioral elements, but festive events are rarely mentioned. We investigated the possible association between the carnival and seasonal fertility variations in the French West Indies. We ran a retrospective registry-based study. The data were extracted from the registry of all births on Guadeloupe between 2000 and 2011 (n = 74,412), and from the Maternity Birth Register of the University Hospital, for all pregnancies of at least 14 completed weeks of gestation (observable conceptions) with an outcome recorded between 2007 and 2010 (n = 8,425). We compared data during and outside the carnival period for each year, including 2009, when there was no carnival due to a 44-day general strike. In all years other than 2009, the weekly number of births was higher for pregnancies initiated during the carnival period than for pregnancies initiated at other times, and the weekly number of observable conceptions was higher during the carnival period than at other times. Our findings support the hypothesis that carnivals in the French West Indies are associated with an increase in the number of conceptions and subsequent births.

Global prevalence of childhood cataract: a systematic review

Childhood cataract is an avoidable cause of visual disability worldwide and is a priority for VISION 2020: The Right to Sight. There is a paucity of information about the burden of cataract in children and the aim of this review is to assess the global prevalence of childhood cataract. The methodology for the review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a literature search for studies reporting estimates of prevalence or incidence of cataract among children (aged<18 years) at any global location using the Cochrane Library, Medline and Embase up to January 2015. No restrictions were imposed based on language or year of publication. Study quality was assessed using a critical appraisal tool designed for systematic reviews of prevalence. Twenty prevalence and four incidence studies of childhood cataract from five different geographical regions were included. The overall prevalence of childhood cataract and congenital cataract was in the range from 0.32 to 22.9/10000 children (median=1.03) and 0.63 to 9.74/10000 (median=1.71), respectively. The incidence ranged from 1.8 to 3.6/10000 per year. The prevalence of childhood cataract in low-income economies was found to be 0.42 to 2.05 compared with 0.63 to 13.6/10000 in high-income economies. There was no difference in the prevalence based on laterality or gender. This review highlights substantial gaps in the epidemiological knowledge of childhood cataract worldwide, particularly from low and lower middle-income economies. More studies are needed using standard definitions and case ascertainment methods with large enough sample sizes.

Congenital anomalies of the kidney and the urinary tract: A murmansk county birth registry study

BACKGROUND

Congenital anomalies of the kidney and the urinary tract (CAKUTs) are relatively common birth defects. The combined prevalence in Europe was 3.3 per 1000 in 2012. The risk factors for these anomalies are not clearly identified. The aims of our study were to calculate the birth prevalences of urinary malformations in Murmansk County during 2006 to 2011 and to investigate related prenatal risk factors.

METHODS

The Murmansk County Birth Registry was the primary source of information and our study included 50,936 singletons in the examination of structure, prevalence and proportional distribution of CAKUTs. The multivariate analyses of risk factors involved 39,322 newborns.

RESULTS

The prevalence of CAKUTs was 4.0 per 1000 newborns (95% confidence interval [CI], 3.4-4.5) and did not change during the study period. The most prevalent malformation was congenital hydronephrosis (14.2% of all cases). Diabetes mellitus or gestational diabetes (odds ratio [OR] = 4.77; 95% CI, 1.16-19.65), acute infections while pregnant (OR = 1.83; 95% CI, 1.14-2.94), the use of medication during pregnancy (OR = 2.03; 95% CI, 1.44-2.82), and conception during the summer (OR = 1.75; 95% CI 1.15-2.66) were significantly associated with higher risk of CAKUTs.

CONCLUSION

The overall fourfold enhancement of the occurrence of urinary malformations in Murmansk County for the 2006 to 2011 period showed little annual dependence. During pregnancy, use of medications, infections, pre-existing diabetes mellitus, or gestational diabetes were associated with increased risk of these anomalies, as was conception during summer. Our findings have direct applications in improving prenatal care in Murmansk County and establishing targets for prenatal screening and women's consultations.

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

This report describes a novel Stata-based application of trigonometric regression modelling to 55 years of multiple sclerosis relapse data from 46 clinical centers across 20 countries located in both hemispheres. Central to the success of this method was the strategic use of plot analysis to guide and corroborate the statistical regression modelling. Initial plot analysis was necessary for establishing realistic hypotheses regarding the presence and structural form of seasonal and latitudinal influences on relapse probability and then testing the performance of the resultant models. Trigonometric regression was then necessary to quantify these relationships, adjust for important confounders and provide a measure of certainty as to how plausible these associations were. Synchronization of graphing techniques with regression modelling permitted a systematic refinement of models until best-fit convergence was achieved, enabling novel inferences to be made regarding the independent influence of both season and latitude in predicting relapse onset timing in MS. These methods have the potential for application across other complex disease and epidemiological phenomena suspected or known to vary systematically with season and/or geographic location.

Long-term trends and seasonality of omphalocele during 1996-2010 in China: a retrospective analysis based on the hospital-based birth defects surveillance system

BACKGROUND

Little is known about secular trends and seasonal variation in the birth prevalence of omphalocele in China. This study aimed to explore the long-term trends and seasonality of this birth defect, to provide insight into the etiology and prevention of omphalocele.

METHODS

A retrospective analysis of all births with omphalocele (1322 cases in 8.8 million births) registered in the hospital-based Chinese Birth Defects Monitoring Network between January 1996 and September 2010. Negative binomial cyclical regression models were used to analyze the long-term trends and seasonal fluctuations of omphalocele occurrence in the southern and northern regions and urban and rural areas of China.

RESULTS

The total prevalence of omphalocele was 1.50 cases (95% confidence interval (CI): 1.42-1.58) per 10,000 births. There was no significant secular trend of omphalocele occurrence in China between 1996 and 2010. The observed prevalence of omphalocele in rural areas was 2.03-2.54 cases per 10,000 births between May and August, which was higher than that observed in other months. The highest prevalence of births with omphalocele in rural areas occurred at the end of June; on average, the prevalence of omphalocele at that time point increased by 20% (95% CI: 6-35%) compared with other months.

CONCLUSIONS

There were no long-term trends found for occurrence of omphalocele in China between 1996 and 2010; however, seasonality was observed for omphalocele in women living in rural areas. These results may help generate hypotheses for further study of environmental factors that vary by season.