Risk of spina bifida and maternal cigarette, alcohol, and coffee use during the first month of pregnancy

Caffeine intake during pregnancy and adverse outcomes: An integrative review

Caffeine intake during pregnancy is common. Caffeine crosses the placenta, raising concerns about its possible deleterious effects on the developing embryo/fetus. Studies on this subject show conflicting results, and still there is no consensus on the recommended dose of caffeine during pregnancy. We performed an integrative review with studies from six databases, using broad MESH terms to allow the identification of publications that addressed the outcomes of caffeine use during pregnancy, with no date limit for publications, in English and Portuguese language. The research returned 16,192 articles. After removing duplicates, screening by title, abstract and full-text, we evaluated 257 and included 59 articles. We found association between caffeine intake and pregnancy loss, low birth weight, cardiac and genital anomalies, higher body mass, and neurodevelopmental and neurobehavioral outcomes. The effects were often dose dependent. No association with prematurity has been demonstrated, but one study showed a small reduction in gestational age with increasing doses of caffeine intake. Defining a safe dose for caffeine intake during pregnancy is a challenging task due to the heterogeneity in study designs and results, as well as the difficulty of reliably assessing the amount of caffeine consumed. In some studies, exposures below the recommended level of caffeine intake during pregnancy (200 mg/day), as suggested by the guidelines, were associated with pregnancy loss, low birth weight, cardiac and genital anomalies, higher body mass, and neurodevelopmental and neurobehavioral outcomes. Well-designed studies with reliable quantification of caffeine intake are needed to assess the safety of low doses during pregnancy.

Maternal dietary caffeine consumption and risk of birth defects in the National Birth Defects Prevention Study, 1997-2011

BACKGROUND

Caffeine consumption is common during pregnancy, but published associations with birth defects are mixed. We updated estimates of associations between prepregnancy caffeine consumption and 48 specific birth defects from the National Birth Defects Prevention Study (NBDPS) for deliveries from 1997 to 2011.

METHODS

NBDPS was a large population-based case-control study conducted in 10 U.S. states. We categorized self-reported total dietary caffeine consumption (mg/day) from coffee, tea, soda, and chocolate as: <10, 10 to <100, 100 to <200, 200 to <300, and ≥ 300. We used logistic regression to estimate adjusted odds ratios (aORs [95% confidence intervals]). Analyses for defects with ≥5 exposed case children were adjusted for maternal race/ethnicity, age at delivery, body mass index, early pregnancy cigarette smoking and alcohol use, and study site.

RESULTS

Our analysis included 30,285 case and 11,502 control children, with mothers of 52% and 54%, respectively, reporting consuming <100 mg caffeine, and 11% of mothers of both cases and controls reported consuming ≥300 mg per day. Low (10 to <100 mg/day) levels of prepregnancy caffeine consumption were associated with statistically significant increases in aORs (1.2-1.7) for 10 defects. Associations with high (≥300 mg/day) levels of caffeine were generally weaker, except for craniosynostosis and aortic stenosis (aORs = 1.3 [1.1-1.6], 1.6 [1.1-2.3]).

CONCLUSIONS

Given the large number of estimates generated, some of the statistically significant results may be due to chance and thus the weakly increased aORs should be interpreted cautiously. This study supports previous observations suggesting lack of evidence for meaningful associations between caffeine consumption and the studied birth defects.

Birth Defects Associated with Prenatal Alcohol Exposure-A Review

Since the recognition of fetal alcohol syndrome, alcohol has been accepted as a human teratogen. However, little is known about the relation between prenatal alcohol exposure and the spectrum of associated major birth defects. The objective of this review was to summarize data on the association of major congenital abnormalities and prenatal alcohol exposure. We included all major birth defects according to ICD-10 classification. We found that the strongest evidence to date lies in the research examining herniation (gastroschisis and omphalocele), oral clefts (cleft lip with or without palate and cleft palate) and cardiac defects. There is less consistent evidence supporting the association between prenatal alcohol exposure and anomalies of gastrointestinal system, diaphragmatic hernia, genitourinary system and neural tube defects. We found no material support for PAE and choanal atresia, biliary atresia or clubfoot.

Caffeine exposure during pregnancy: Is it safe?

Numerous studies have examined the association between maternal caffeine consumption and infant and childhood health outcomes and the results have been inconsistent. The study of maternal caffeine intake and infant and childhood health outcomes is prone to methodologic challenges. In this review, we examine the existing evidence juxtaposed with the epidemiologic design challenges that color the interpretation of the study results presented. In light of methodologic/interpretation challenges, it seems reasonable to infer that exposure to low levels of caffeine is probably not associated with substantial infant and childhood adversities. However, more research is needed using well designed studies that address methodologic challenges.

Determinants of Neural Tube Defects among Newborns in Amhara Region, Ethiopia: A Case-Control Study

BACKGROUND

Worldwide, an estimated 300,000 neonates are born with neural tube defects (NTDs) each year. However, NTDs are underreported in Ethiopia though it causes substantial mortality, morbidity, disability, and psychological and economic cost in the country. Moreover, the factors attributed to NTDs were not addressed. Hence, this study intended to identify the determinants of neural tube defects in Amhara Region, Ethiopia.

METHODS

A case-control study design was conducted among 400 newborns (133 cases and 267 controls) who were born at randomly selected public hospitals. Cases were identified using the physician diagnosis of confirmed NTDs, and the two consecutive controls were selected using a simple random sampling technique. The data analysis was done using Stata 14.0. Variables with p value < 0.25 in the bivariate analysis were entered into the multivariable logistic regression model, and a corresponding 95% confidence interval was used to identify the predictors of NTDs.

RESULTS

In this study, fifty percent (48%) of the cases were contributed by anencephaly. After controlling the covariates, living in rural areas (AOR = 1.78: 95% CI 1.02, 3.11), being illiterate (AOR = 1.81: 95% CI 1.07, 4.61), being female newborn (AOR = 1.95: 95% CI 1.09, 3.50), having no ANC follow-up (AOR = 1.93: 95% CI 1.17, 5.04), and having a previous history of NTDs (AOR = 4.39: 95% CI 2.42, 7.96) were the risk factors for NTDs. However, being supplemented with folic acid or multivitamins before or during pregnancy (AOR = 0.37: 95% CI 0.21, 0.65), never having taken any substance during pregnancy (AOR = 0.42: 95% CI 0.21, 0.88), and being free from medical illnesses during pregnancy (AOR = 0.27: 95% CI 0.11, 0.69) were the protective factors of NTDs.

CONCLUSION

The study revealed different factors associated with NTDs among newborns in the region. Therefore, comprehensive preventive strategies focused on identified risk factors are needed at regional and national levels.

Association of paternal smoking with the risk of neural tube defects in offspring: A systematic review and meta-analysis of observational studies

PURPOSE

The present study aimed at providing some epidemiological evidences to assess the association of paternal smoking with the risk of neural tube defects (NTDs) and its specific subtypes in offspring, and explore the possible dose-response relationship between paternal smoking and risk of NTDs.

METHODS

English and Chinese databases were systematically searched from 1984 to May 2020. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates. We also examined the dose-response relationship between parental smoking and risk of NTDs in offspring. Subgroup analyses and sensitivity analyses were conducted to explore possible sources of heterogeneity.

RESULTS

A total of 10 case-control studies involving 2,593 cases of NTDs and 45,100 controls were included for analysis. Findings from our study showed that paternal smoking was significantly associated with risk of total NTDs (odds ratio [OR] = 1.68; 95% confidence interval (CI): 1.48-1.92) and two subtypes including anencephaly (OR = 1.41; 95% CI: 1.06-1.86) and encephaloceles (OR = 2.90; 95% CI: 1.00-8.41). Additionally, a linear dose-response relationship between paternal smoking and risk of NTDs was observed, which indicated that the risk of NTDs in offspring was significantly increased by 45% (OR = 1.45, 95% CI: 1.14-1.84) for each increment of half a pack of cigarettes per day. Sensitivity analyses yielded consistent results. No evidence of publication bias was found.

CONCLUSIONS

Paternal smoking is significantly associated with the risk of NTDs in offspring. Therefore, it should be recommended that fathers quit smoking before pregnancy to prevent NTDs in offspring.

Maternal intake of caffeinated products and birth defects: a systematic review and meta-analysis of observational studies

Caffeinated products are frequently consumed by women of childbearing age worldwide. It still unclear that whether maternal intake of caffeine associated with an increased risk of birth defects. We searched the databases of PubMed, Embase, the Cochrane Library, and Web of Science for eligible studies through July 2020. All studies examining the association between maternal consumption of caffeine or caffeinated products and birth defects were included. Twenty-nine studies were included in this meta-analysis. Among all the birth defects, maternal caffeine consumption was associated with a higher risk of cardiovascular defects, [odds ratio (OR) 1.17; 95% confidence interval (CI), 1.07-1.28], craniofacial defects (OR 1.09; 95% CI, 1.02-1.17), alimentary tract defects (OR 1.35; 95% CI, 1.16-1.56), and abdominal-wall defects and hernia (OR 1.13; 95% CI, 1.03-1.25). No association was found between maternal caffeine intake and musculoskeletal system defects, genitourinary system defects, nervous system defects, or chromosomal abnormalities. Meanwhile, all three of the caffeine consumption categories (low, moderate, and high) were associated with a higher risk of cardiovascular defects and alimentary tract defects.

Association between maternal periconceptional alcohol consumption and neural tube defects: Findings from the National Birth Defects Prevention Study, 1997-2011

BACKGROUND

Neural tube defects (NTD)s are common birth defects with a multifactorial etiology. Findings from human studies examining environmental (non-inherited) exposures tend to be inconclusive. In particular, although animal studies of alcohol exposure and NTDs support its teratogenic potential, human studies are equivocal. Using data from the National Birth Defects Prevention Study (NBDPS), associations between maternal periconceptional (1 month before through 1 month after conception) alcohol consumption and NTDs in offspring were examined.

METHODS

NTD cases and unaffected live born singleton controls with expected dates of delivery from October 1997-December 2011 were enrolled in the NBDPS. Interview reports of alcohol consumption (quantity, frequency, variability, type) from 1,922 case and 11,251 control mothers were analyzed. Crude and adjusted odds ratios (aOR)s and 95% confidence intervals (CI)s for alcohol consumption and all NTDs combined and selected subtypes (spina bifida, anencephaly, encephalocele) were estimated using unconditional logistic regression analysis.

RESULTS

Among mothers in the NBDPS, 28% of NTD case and 35% of control mothers reported any periconceptional alcohol consumption. For each measure of alcohol consumption, inverse associations were observed for all NTDs combined (aORs = 0.6-1.0). Results for NTD subtypes tended to be similar, but CIs for spina bifida and encephalocele were more likely to include the null.

CONCLUSIONS

These findings suggest a lack of positive associations between maternal periconceptional alcohol consumption and NTDs. Future studies should continue to evaluate the association between maternal alcohol consumption and NTDs in offspring accounting for methodological limitations such as potential misclassification from self-reported alcohol consumption.

Meta-analysis of the association of maternal smoking and passive smoking during pregnancy with neural tube defects

BACKGROUND

It is unclear whether the incidence of neural tube defects (NTDs) is greater with maternal smoking or with passive smoking during pregnancy.

OBJECTIVES

To compare the effects of smoking and passive smoking during pregnancy on the risk of NTDs.

SEARCH STRATEGY

English and Chinese databases were searched for relevant papers published before March 2017, using search terms including "smoking" and "NTD."

SELECTION CRITERIA

Case-control and cohort studies on the aforementioned association were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the original data. Meta-analyses were performed to assess the risks associated with smoking and passive smoking, followed by a comparison of the two pooled effect estimates. The I² statistic was used to examine between-study heterogeneity.

MAIN RESULTS

The final analysis included 23 articles representing 33 studies. The pooled odds ratio (OR) and 95% confidence interval (CI) for the risk of NTDs was 1.052 (0.907-1.220) with smoking and 1.898 (1.557-2.313) with passive smoking. Comparison of these ORs indicated that the risk of NTDs was higher with passive smoking than with smoking (OR 1.804, 95% CI 1.409-2.309).

CONCLUSIONS

Compared with smoking, exposure to passive smoking during pregnancy carries a higher risk of having infants with NTDs.

Neural tube defects: Risk factors and preventive measures

For the last 25 years, it has been proven that the occurrence or recurrence of neural tube defects can be prevented with the administration of folic acid before and early pregnancy. At present, over 80 countries in the world, except Japan, have mandated the fortification of wheat flour and/or rice with folic acid, which has resulted in a significant reduction in the prevalence of neural tube defects. In 2000, the Japanese government recommended folic acid 400 μg daily for young women of childbearing age and women who are planning to conceive. In 2002, the government started to present information about the importance of folic acid in the development of fetuses in the Mother-Child Health Booklet annually. Despite these endeavors, the prevalence of neural tube defects has remained unchanged. We discuss the risk factors of neural tube defects and propose preventive measures to decrease the number of neonates with neural tube defects. We believe that the government should implement the fortification of staple food with folic acid very soon, which will eventually decrease not only the neonatal mortality and morbidity, but also the economic burden on our health care system.

Risk factors associated with neural tube defects in infants referred to western Iranian obstetrical centers; 2013-2014

BACKGROUND

Neural tubes defects (NTDs) are known to be the second most prevalent congenital disorder worldwide whose risk factors have not been explicitly addressed yet.

AIM

To determine the risk factors affecting NTDs among infants who referred to obstetrical centers in Kurdistan, a western province of Iran.

METHODS

This prospective case-control study was conducted in the form of prospective case-control. Sample population included all women (27,153 cases) who referred to obstetrical centers in Kurdistan for either delivery or abortion during 2013 and 2014. Inclusion criterion was the presence of a known NTD in infants, and exclusion criterion was the reluctance of patients to participate in the study. Accordingly, 46 cases participated in the study as the case group, and 138 cases (three times higher than case group) were selected to be the control group. Case and control groups were matched in terms of the number of pregnancies and place of birth. The variables investigated in the present study were as follows: age, occupation, BMI, abortion history, family relation with husband, fetus' sex, number of twins, history of previous children with NTD, receiving prenatal surveillance, consumption of folic acid and multivitamins, smoking, alcohol drinking, passive smoking, and suffering from such diseases as epilepsy and diabetes. Data were analyzed using various statistical tests, including chi-square, Fishers' exact test, multiple logistic regression analysis using SPSS version 20. In the study group, inclusion criteria included all women who had an infant with tube defects that their total number was 46 individuals. In the control group inclusion criteria included mothers with healthy infants who were similar to the study group in terms of birth place and frequency of pregnancy.

RESULTS

The results of the present study demonstrated that prenatal surveillance (p<0.002), multivitamin consumption (p<0.001), history of having a child with NTD (p<0.001), alcohol drinking (p<0.014), and passive smoking were related to NTDs (p<0.001).

CONCLUSION

Before fertilization and during pregnancy, mothers should be examined in terms of exposure to harmful agents, diet, and nutritional status in order to identify possible risk factors and find opportunities to prevent NTDs in infants.

Caffeine: Friend or Foe?

The debate on the safety of and regulatory approaches for caffeine continues among various stakeholders and regulatory authorities. This decision-making process comes with significant challenges, particularly when considering the complexities of the available scientific data, making the formulation of clear science-based regulatory guidance more difficult. To allow for discussions of a number of key issues, the North American Branch of the International Life Sciences Institute (ILSI) convened a panel of subject matter experts for a caffeine-focused session entitled "Caffeine: Friend or Foe?," which was held during the 2015 ILSI Annual Meeting. The panelists' expertise covered topics ranging from the natural occurrence of caffeine in plants and interindividual metabolism of caffeine in humans to specific behavioral, reproductive, and cardiovascular effects related to caffeine consumption. Each presentation highlighted the potential risks, benefits, and challenges that inform whether caffeine exposure warrants concern. This paper aims to summarize the key topics discussed during the session.

Maternal Coffee Consumption During Pregnancy and Neural Tube Defects in Offspring: A Meta-Analysis

PURPOSE

To examine the association between maternal coffee consumption during pregnancy and the occurrence of neural tube defects (NTDs) in offspring.

METHODS

PubMed, Springer Link and Elsevier databases were searched up to August, 2014. Case-control and cohort studies published on the association between maternal coffee consumption during pregnancy and the occurrence of NTDs in offspring were included. Meta-analysis was applied to calculate the pooled effect estimates and their 95% confidence intervals (CIs) using a random-effects model.

RESULTS

A total of six case-control studies and one cohort study were included. The pooled effect estimate of maternal coffee consumption during pregnancy was 0.86 for total NTDs (95% CI: 0.51- 1.45) and 1.30 (95% CI: 0.67- 2.52) for NTDs subtype of spina bifida.

CONCLUSIONS

Our findings suggested that maternal coffee consumption during pregnancy was not significantly associated with the occurrence of total NTD or the spina bifida subtype of NTD.

Maternal periconceptional alcohol consumption and the risk of neural tube defects in offspring: a meta-analysis

OBJECTIVE

Several studies have been conducted to examine the association between alcohol consumption during pregnancy and risk of neural tube defects (NTDs), while the results are inconsistent. In the present study, we aimed to clarify the relationship between maternal periconceptional alcohol consumption and NTDs risk in offspring.

METHODS

PubMed, Springer Link, and Elsevier databases were searched up to November, 2014. All case-control and cohort studies of maternal alcohol consumption during pregnancy with risk of NTDs were included. The pooled odds ratios (ORs) and their 95% confidence intervals (CIs) for highest versus lowest category of alcohol consumption were calculated using a fixed- or random-effects model.

RESULTS

The pooled ORs of maternal periconceptional alcohol consumption were 1.01 (95% CI: 0.71-1.45) for total NTDs and 1.03 (95% CI: 0.65-1.64) for NTDs subtype of spina bifida. Specifically, the pooled ORs of maternal alcohol consumption in the first trimester and binge drinking were 1.01 (95% CI: 0.71-1.43), and 1.07 (95% CI: 0.81-1.41), respectively.

CONCLUSIONS

Our findings suggested no association between maternal periconceptional alcohol consumption and NTDs risk in offspring.

Genetic, epigenetic, and environmental contributions to neural tube closure

The formation of the embryonic brain and spinal cord begins as the neural plate bends to form the neural folds, which meet and adhere to close the neural tube. The neural ectoderm and surrounding tissues also coordinate proliferation, differentiation, and patterning. This highly orchestrated process is susceptible to disruption, leading to neural tube defects (NTDs), a common birth defect. Here, we highlight genetic and epigenetic contributions to neural tube closure. We describe an online database we created as a resource for researchers, geneticists, and clinicians. Neural tube closure is sensitive to environmental influences, and we discuss disruptive causes, preventative measures, and possible mechanisms. New technologies will move beyond candidate genes in small cohort studies toward unbiased discoveries in sporadic NTD cases. This will uncover the genetic complexity of NTDs and critical gene-gene interactions. Animal models can reveal the causative nature of genetic variants, the genetic interrelationships, and the mechanisms underlying environmental influences.