Maternal body mass index and lifestyle exposures and the risk of bilateral renal agenesis or hypoplasia: the National Birth Defects Prevention Study

Bilateral renal agenesis: fetal intervention and outcomes

Bilateral renal agenesis (BRA) is a fetal anomaly which leads to anhydramnios and resultant pulmonary hypoplasia. Historically, this anomaly was universally fatal early in the neonatal period due to the severity of the associated lung disease. Over the last 30 years, innovations in fetal therapies-specifically, serial amnioinfusions-have led to instances of infant pulmonary survival and initiation of postnatal dialysis, raising the possibility that early neonatal death may not be inevitable. Amnioinfusions are not without risk, and maternal complications can include prelabor rupture of membranes, preterm labor, infection, and bleeding. The data detailing neonatal outcomes are still limited and actively being collected. Two case series and one non-randomized clinical trial have supplied most of the known outcome data for infants with BRA after prenatal amnioinfusion. Although there are survivors reported in the literature, mortality remains high, with many deaths in infancy due to dialysis-associated sepsis. In addition, previously unknown morbidities have been documented in these infants, including neurologic injury. These challenges, in addition to the mechanical difficulties of providing dialysis to extremely small infants, can result in significant burdens for patients and their caregivers and moral distress for the health care team. The present review aims to explain the pathophysiology of BRA, detail the historical context and rationale for serial amnioinfusions to treat the pulmonary insufficiency associated with BRA, describe the available data regarding outcomes of infants born following prenatal amnioinfusions, discuss ethical issues surrounding this fetal intervention, and describe critical aspects of prenatal counseling for patients considering the intervention.

Increased incidence of renal and urinary tract anomalies among individuals with fetal alcohol spectrum disorders (FASD)

BACKGROUND

Fetal alcohol spectrum disorders (FASD) in a spectrum of neurodevelopmental conditions resulting from prenatal alcohol exposure (PAE). Animal models have confirmed the toxic effects of PAE on the kidneys and urinary tract, yet the evidence from human studies is contradictory. The purpose of this study was to establish the incidence of renal and urinary tract anomalies (RUTA), impaired kidney function, and hypertension among patients with FASD.

METHODS

Children from the FASD Diagnostic Center with FASD diagnosis (FAS, pFAS, or ARND) were offered participation in the study. The control group consisted of patients from the Gastroenterology Department of the same hospital. The patients underwent renal and urinary tract ultrasound examination. The serum creatinine level was also evaluated and the blood pressure was taken twice. Polish OLAF charts were used to determine the percentiles of blood pressure.

RESULTS

The incidence of kidney and urinary tract defects in the study group was significantly higher than in the control group (OR: 2.64 [1.60-4.34]). The kidney size among FASD patients was significantly lower (73 mm [60-83] vs. 83 mm [70-96]; p < .001) when compared to the control group. No differences were observed in the estimated glomerular filtration rate. In the study group, significantly lower systolic blood, diastolic blood pressure, percentile of systolic pressure, and diastolic pressure were observed.

CONCLUSIONS

RUTA occurred more frequently among patients with FASD compared to the control group, and decreased kidney size was also demonstrated among patients with FASD. However, impaired kidney function and the risk of hypertension were not observed.

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.

Maternal risk factors for congenital anomalies of the kidney and urinary tract: A case-control study

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) are significant causes of pediatric morbidity and mortality. The spectrum of CAKUT can be part of a syndrome, but most of these abnormalities occur as isolated and sporadic forms. The etiology of human CAKUT is unknown in the majority of cases. This case-control study aimed to investigate the association between maternal characteristics and the occurrence of CAKUT and specific CAKUT phenotypes.

METHODS

In this case-control study, 29,653 newborns were evaluated consecutively in a tertiary neonatal unit using the Latin American Collaborative Study of Congenital Malformations (ECLAMC) registry. Newborns without congenital anomalies were matched to CAKUT cases by sex, date, and place of birth at a ratio of 3:1. For analysis purposes, the cases were stratified into four subgroups: upper tract abnormalities (UTA), including ureteropelvic junction obstruction, vesicoureteral reflux, primary megaureter and others (n = 239), lower urinary tract obstruction (LUTO) (n = 79), cystic diseases (n = 59) and agenesis/hypodysplasia (n = 28). Multivariable logistic regression analyses were used to calculate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for associations between the maternal risk factors and the presence of CAKUT.

RESULTS

The prevalence of non-syndromic CAKUT in our sample was 13 per 1000 live births. Data records allowed the analysis of 405 cases and 1208 controls. After adjustment by the binary regression logistic, three covariates remained associated as risk factors for the entire spectrum of CAKUT: consanguinity (Odds ratio [OR], 7.1, 95%CI, 2.4-20.4), family history of CAKUT (OR, 6.4, 95%CI, 1.9-21.3), and maternal chronic hypertension (OR, 14.69, 95%CI, 3.2-67.5) (Figure). These risk factors persisted consistently across the various CAKUT phenotypes with minor variations. Consanguinity was the only factor consistently associated with almost all CAKUT phenotypes. Maternal hypertension was associated with all phenotypes except for the agenesis/hypodysplasia group. The prevalence of CAKUT cases was 15 times higher in hypertensive mothers (3%) compared to normotensive mothers (0.2%).

CONCLUSION

Our study suggests that an increased risk of CAKUT is associated with consanguinity, a positive family history of CAKUT, and maternal hypertension. However, the prevalence of these risk factors in our cohort was rare and most cases presented as sporadic forms.

Glycemic and nonglycemic mechanisms of congenital malformations in hyperglycemic pregnancies: a narrative review

Congenital malformations are more frequently found among children born to mothers with diabetes than in the background population. There are several complex mechanisms involved in the development of congenital malformations in the offspring of mothers with hyperglycemia, such as the overexpression of glucose transporters (GLUTs) 1 and 2, the increased activity of the hexosamine biosynthetic pathway and the reduced expression of the PAX3 gene with a consequent increase in p53 protein expression. These alterations can lead to increased glucose and free radical concentrations in the embryo, thus promoting the process of apoptosis and causing malformation. The most frequent malformations found in the offspring of mothers with diabetes are heart and neural tube defects, urinary tract and kidney malformations, and cleft lip with or without cleft palate. Strict glycemic control should be obtained before and during pregnancy, aiming to avoid or minimize the risk of congenital malformations in the offspring. Beyond hyperglycemia, several factors may also be associated with increased risks of malformations in the offspring of these women, such as obesity, multiple pregnancies, advanced maternal age, folic acid deficiency, use of angiotensin converting enzyme inhibitors and angiotensin receptor blockers, assisted reproduction techniques, and exposure to different types of environmental pollutants.

Maternal smoking during pregnancy and the risk of congenital urogenital malformations: A systematic review and meta-analysis

BACKGROUND

Investigations regarding the association between maternal smoking and specific urogenital teratogenesis exist. However, an integrated systematic review and meta-analysis studying the relationship by encompassing the whole urogenital system is essential.

OBJECTIVE

Even though many studies about inborn urogenital malformations have been conducted, its etiologic factors and exact pathogenesis are still unclear. Our aim is to assess the risk of congenital urogenital malformations in offspring of smoking pregnant women.

RESULTS

The meta-analysis, covering 41 case-control and 11 cohort studies, suggested that maternal smoking was associated with an increased risk of urogenital teratogenesis (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 1.04-1.23, p = 0.005), cryptorchidism (OR = 1.18, 95%CI: 1.12-1.24, p = 0.0001), hypospadias (OR = 1.16, 95%CI: 1.01-1.33, p = 0.039), and kidney malformations (OR = 1.30, 95%CI: 1.14-1.48, p = 0.0001). Moreover, paternal smoking during the mother's pregnancy was also significantly associated (OR = 1.26, 95%CI: 1.03-1.55, p = 0.028). The association between smoking > 10 cigarettes/day was evident but was not significant (OR = 1.24, 95%CI:0.81-1.88, p = 0.323).

CONCLUSION

Our results showed that maternal smoking during pregnancy increased the risk of congenital urogenital malformations. In numerous epidemiological studies, maternal smoking during pregnancy has a significant role in fetal development. Therefore, quitting tobacco use may be an effective method for reducing the risk of congenital urogenital malformation in pregnant women.

Pre-pregnancy obesity and risk of congenital abnormalities of the kidney and urinary tract (CAKUT)-systematic review, meta-analysis and ecological study

BACKGROUND

There is increasing evidence that maternal obesity is associated with several structural birth defects. Congenital abnormalities of the kidney and urinary tract (CAKUT) account for 30 to 50% of children starting kidney replacement therapy (KRT). We conducted a systematic review, meta-analysis and ecological study to explore the relationship between maternal obesity and CAKUT.

METHODS

A systematic literature search was conducted in EMBASE, MEDLINE, Global Health, The Cochrane Library, Scopus and Web of Science. Study quality was assessed for bias and confounding. A meta-analysis using a random effect model was carried out to obtain a summary odds ratio (OR) and 95% confidence interval (CI). In the ecological study, country-level data were used to examine the correlation of secular trends in female obesity, CAKUT incidence and incidence of KRT.

RESULTS

Eight epidemiological studies were included in the review-4 cohort studies and 4 case-control studies-7 of which were included in the meta-analysis. There was evidence of a positive association between obesity during pregnancy and the risk of CAKUT, with a summary OR = 1.14 (1.02-1.27). No association was seen with overweight, nor a dose response with increasing obesity. There was an increasing trend in countries' proportion of female obesity and an increasing trend in reported CAKUT incidence with specific rises seen in congenital hydronephrosis (CH) and multicystic kidney dysplasia (MCKD).

CONCLUSIONS

Our findings suggest that pre-pregnancy obesity may be associated with increased risk of CAKUT at population level. Graphical abstract.

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.

The association between gestational use of personal care products and neonatal urological abnormality at birth: The Japan Environment and Children's Study

Congenital anomalies of the kidney and urinary tract (CAKUT) include a broad group of birth defects. Exposure to endocrine disrupting chemicals (EDCs) is suspected to be one of the risk factors for CAKUT, and the use of personal care products (PCPs) is a source of EDC exposure. Therefore, this study aimed to investigate the relationship between CAKUT and the use of PCPs in a large birth cohort study. Data from 86,899 pregnant women included in the Japan Environment and Children's Study (JECS), an ongoing nationwide project, were analyzed. The prevalence of CAKUT in newborns was 0.25 % and almost 90 % of subjects used PCPs during mid-late pregnancy. No association was found between CAKUT and PCP use in a model adjusted for the following covariates: maternal age at delivery. The result was persistent after rigorous sensitivity analyses.

Fetal alcohol spectrum disorders - diagnostic difficulties in the neonatal period and new diagnostic approaches

Fetal alcohol spectrum disorders (FASD) is a group of disorders that can occur in children whose mothers consumed alcohol in pregnancy. Diagnosis of fetal alcohol syndrome is based on the appearance of growth deficiency, the presence of the three key features of facial dysmorphism (short palpebral fissures, thin upper lip, smooth or flattend philtrum) and/or disorders in the central nervous system (minimum 3) and prenatal exposure to alcohol (confirmed if possible). Early diagnosis of fetal alcohol syndrome - after birth or in infancy - is very often impossible or very difficult due to the incomplete manifestation of the key dysmorphic features. The latest reports offer the chance of diagnosing children in the neonatal period. The research focuses on the analysis of ethanol metabolites in the biological tissues in pregnant women or newborns. These unique ethanol metabolites include: fatty acid ethyl esters (FAEE) present in the meconium, blood, hair of the mother and the newborn, ethyl glucuronide in the placenta and meconium, urine, nails and hair, and phosphatidylethanol (PEth) found in the infant blood. The presence of fatty acid ethyl esters in the meconium could be a non-invasive and cost-effective method of early detection of disorders associated with prenatal alcohol exposure.

Maternal obesity increases the risk of metabolic disease and impacts renal health in offspring

Obesity, together with insulin resistance, promotes multiple metabolic abnormalities and is strongly associated with an increased risk of chronic disease including type 2 diabetes (T2D), hypertension, cardiovascular disease, non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD). The incidence of obesity continues to rise in astronomical proportions throughout the world and affects all the different stages of the lifespan. Importantly, the proportion of women of reproductive age who are overweight or obese is increasing at an alarming rate and has potential ramifications for offspring health and disease risk. Evidence suggests a strong link between the intrauterine environment and disease programming. The current review will describe the importance of the intrauterine environment in the development of metabolic disease, including kidney disease. It will detail the known mechanisms of fetal programming, including the role of epigenetic modulation. The evidence for the role of maternal obesity in the developmental programming of CKD is derived mostly from our rodent models which will be described. The clinical implication of such findings will also be discussed.

Cigarette Smoking Impairs Adipose Stromal Cell Vasculogenic Activity and Abrogates Potency to Ameliorate Ischemia

Cigarette smoking (CS) adversely affects the physiologic function of endothelial progenitor, hematopoietic stem and progenitor cells. However, the effect of CS on the ability of adipose stem/stromal cells (ASC) to promote vasculogenesis and rescue perfusion in the context of ischemia is unknown. To evaluate this, ASC from nonsmokers (nCS-ASC) and smokers (CS-ASC), and their activity to promote perfusion in hindlimb ischemia models, as well as endothelial cell (EC) survival and vascular morphogenesis in vitro were assessed. While nCS-ASC improved perfusion in ischemic limbs, CS-ASC completely lost this therapeutic effect. In vitro vasculogenesis assays revealed that human CS-ASC and ASC from CS-exposed mice showed compromised support of EC morphogenesis into vascular tubes, and the CS-ASC secretome was less potent in supporting EC survival/proliferation. Comparative secretome analysis revealed that CS-ASC produced lower amounts of hepatocyte growth factor (HGF) and stromal cell-derived growth factor 1 (SDF-1). Conversely, CS-ASC secreted the angiostatic/pro-inflammatory factor Activin A, which was not detected in nCS-ASC conditioned media (CM). Furthermore, higher Activin A levels were measured in EC/CS-ASC cocultures than in EC/nCS-ASC cocultures. CS-ASC also responded to inflammatory cytokines with 5.2-fold increase in Activin A secretion, whereas nCS-ASC showed minimal Activin A induction. Supplementation of EC/CS-ASC cocultures with nCS-ASC CM or with recombinant vascular endothelial growth factor, HGF, or SDF-1 did not rescue vasculogenesis, whereas inhibition of Activin A expression or activity improved network formation up to the level found in EC/nCS-ASC cocultures. In conclusion, ASC of CS individuals manifest compromised in vitro vasculogenic activity as well as in vivo therapeutic activity. Stem Cells 2018;36:856-867.

Evidence-based, ethically justified counseling for fetal bilateral renal agenesis

BACKGROUND

Not much data are available on the natural history of bilateral renal agenesis, as the medical community does not typically offer aggressive obstetric or neonatal care asbilateral renal agenesis has been accepted as a lethal condition.

AIM

To provide an evidence-based, ethically justified approach to counseling pregnant women about the obstetric management of bilateral renal agenesis.

STUDY DESIGN

A systematic literature search was performed using multiple databases. We deploy an ethical analysis of the results of the literature search on the basis of the professional responsibility model of obstetric ethics.

RESULTS

Eighteen articles met the inclusion criteria for review. With the exception of a single case study using serial amnioinfusion, there has been no other case of survival following dialysis and transplantation documented. Liveborn babies die during the neonatal period. Counseling pregnant women about management of pregnancies complicated by bilateral renal agenesis should be guided by beneficence-based judgment informed by evidence about outcomes.

CONCLUSIONS

Based on the ethical analysis of the results from this review, without experimental obstetric intervention, neonatal mortality rates will continue to be 100%. Serial amnioinfusion therefore should not be offered as treatment, but only as approved innovation or research.

Risk Factors for Birth Defects

Importance

Major congenital abnormalities, or birth defects, carry significant medical, surgical, cosmetic, or lifestyle consequences. Such abnormalities may be syndromic, involving multiple organ systems, or can be isolated. Overall, 2% to 4% of live births involve congenital abnormalities. Risk factors for birth defects are categorized as modifiable and nonmodifiable. Modifiable risk factors require thorough patient education/counseling. The strongest risk factors, such as age, family history, and a previously affected child, are usually nonmodifiable.

Objective

This review focuses on risk factors for birth defects including alcohol consumption, illicit drug use, smoking, obesity, pregestational diabetes, maternal phenylketonuria, multiple gestation, advanced maternal age, advanced paternal age, family history/consanguinity, folic acid deficiency, medication exposure, and radiation exposure.

Evidence Acquisition

Literature review via PubMed.

Results

There is a strong link between alcohol use, folic acid deficiency, obesity, uncontrolled maternal diabetes mellitus, uncontrolled maternal phenylketonuria, and monozygotic twins and an increased risk of congenital anomalies. Advanced maternal age confers an increased risk of aneuploidy, as well as nonchromosomal abnormalities. Some medications, including angiotensin converting enzyme inhibitors, retinoic acid, folic acid antagonists, and certain anticonvulsants, are associated with various birth defects. However, there are few proven links between illicit drug use, smoking, advanced paternal age, radiation exposure, and statins with specific birth defects.

Conclusions and Relevance

Birth defects are associated with multiple modifiable and nonmodifiable risk factors. Obstetrics providers should work with patients to minimize their risk of birth defects if modifiable risk factors are present and to appropriately counsel patients when nonmodifiable risk factors are present.

Associations between maternal periconceptional exposure to secondhand tobacco smoke and major birth defects

BACKGROUND

While associations between secondhand smoke and a few birth defects (namely, oral clefts and neural tube defects) have been noted in the scientific literature, to our knowledge, there is no single or comprehensive source of population-based information on its associations with a range of birth defects among nonsmoking mothers.

OBJECTIVE

We utilized data from the National Birth Defects Prevention Study, a large population-based multisite case-control study, to examine associations between maternal reports of periconceptional exposure to secondhand smoke in the household or workplace/school and major birth defects.

STUDY DESIGN

The multisite National Birth Defects Prevention Study is the largest case-control study of birth defects to date in the United States. We selected cases from birth defect groups having >100 total cases, as well as all nonmalformed controls (10,200), from delivery years 1997 through 2009; 44 birth defects were examined. After excluding cases and controls from multiple births and whose mothers reported active smoking or pregestational diabetes, we analyzed data on periconceptional secondhand smoke exposure-encompassing the period 1 month prior to conception through the first trimester. For the birth defect craniosynostosis, we additionally examined the effect of exposure in the second and third trimesters as well due to the potential sensitivity to teratogens for this defect throughout pregnancy. Covariates included in all final models of birth defects with ≥5 exposed mothers were study site, previous live births, time between estimated date of delivery and interview date, maternal age at estimated date of delivery, race/ethnicity, education, body mass index, nativity, household income divided by number of people supported by this income, periconceptional alcohol consumption, and folic acid supplementation. For each birth defect examined, we used logistic regression analyses to estimate both crude and adjusted odds ratios and 95% confidence intervals for both isolated and total case groups for various sources of exposure (household only; workplace/school only; household and workplace/school; household or workplace/school).

RESULTS

The prevalence of secondhand smoke exposure only across all sources ranged from 12.9-27.8% for cases and 14.5-15.8% for controls. The adjusted odds ratios for any vs no secondhand smoke exposure in the household or workplace/school and isolated birth defects were significantly elevated for neural tube defects (anencephaly: adjusted odds ratio, 1.66; 95% confidence interval, 1.22-2.25; and spina bifida: adjusted odds ratio, 1.49; 95% confidence interval, 1.20-1.86); orofacial clefts (cleft lip without cleft palate: adjusted odds ratio, 1.41; 95% confidence interval, 1.10-1.81; cleft lip with or without cleft palate: adjusted odds ratio, 1.24; 95% confidence interval, 1.05-1.46; cleft palate alone: adjusted odds ratio, 1.31; 95% confidence interval, 1.06-1.63); bilateral renal agenesis (adjusted odds ratio, 1.99; 95% confidence interval, 1.05-3.75); amniotic band syndrome-limb body wall complex (adjusted odds ratio, 1.66; 95% confidence interval, 1.10-2.51); and atrial septal defects, secundum (adjusted odds ratio, 1.37; 95% confidence interval, 1.09-1.72). There were no significant inverse associations observed.

CONCLUSION

Additional studies replicating the findings are needed to better understand the moderate positive associations observed between periconceptional secondhand smoke and several birth defects in this analysis. Increased odds ratios resulting from chance (eg, multiple comparisons) or recall bias cannot be ruled out.

Maternal smoking during pregnancy and birth defects in children: a systematic review with meta-analysis

This systematic review aimed to investigate the association between maternal smoking during pregnancy and birth defects in children. We performed an electronic search of observational studies in the databases ovid MEDLINE (1950 to April 2010), LILACS and SciELO. We included 188 studies with a total of 13,564,914 participants (192,655 cases). Significant positive associations were found between maternal smoking and birth defects in the following body systems: cardiovascular (OR: 1.11; 95%CI: 1.03-1.19), digestive (OR: 1.18; 95%CI: 1.07-1.30), musculoskeletal (OR: 1.27; 95%CI: 1.16-1.39) and face and neck (OR: 1.28; 95%CI: 1.19-1.37). The strength of association between maternal smoking and birth defects measured by the OR (95%CI) is significantly related to the amount of cigarettes smoked daily (χ2 = 12.1; df = 2; p = 0.002). In conclusion, maternal smoking during pregnancy is associated with congenital malformations in children and this association is dose-dependent.

Maternal risk factors involved in specific congenital anomalies of the kidney and urinary tract: A case-control study

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) comprise a heterogeneous group of birth defects with a variety of genetic and nongenetic factors suspected of involvement in the etiology. However, little is known about risk factors in specific CAKUT phenotypes. Therefore, we studied potential maternal risk factors in individual phenotypes within the CAKUT spectrum.

METHODS

Questionnaire data were collected from parents of 562 children with CAKUT and 2139 healthy controls within the AGORA data- and biobank. Potential maternal risk factors investigated included folic acid use, overweight and obesity, smoking, alcohol consumption, subfertility, and diabetes mellitus. We performed logistic regression analyses to assess associations between these potential risk factors and CAKUT phenotypes.

RESULTS

Increased risks of CAKUT were observed for folic acid use and maternal obesity, while fertility treatment by in vitro fertilization or intrauterine insemination and diabetes diagnosed during pregnancy also seem to be associated with CAKUT. Use of multivitamins reduced the risk (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.2-1.0) as opposed to use of folic acid supplements only (OR, 1.3; 95% CI, 1.0-1.8). Folic acid use was associated with duplex collecting systems (OR, 1.8; 95% CI, 1.0-3.4) and vesicoureteral reflux (OR, 1.8; 95% CI, 1.1-2.9) in particular. A relatively strong association was observed between diabetes during pregnancy and posterior urethral valves (OR, 2.6; 95% CI, 1.1-5.9).

CONCLUSION

Use of folic acid only seems to be counterproductive for prevention of CAKUT, in contrast to multivitamin use. Furthermore, we observed differences in risk factor patterns among CAKUT phenotypes, which stress the importance of separate analyses for each phenotype. Birth Defects Research (Part A) 106:596-603, 2016. © 2016 Wiley Periodicals, Inc.

Maternal exposures in the National Birth Defects Prevention Study: Time trends of selected exposures

BACKGROUND

Our objective was to describe time trends in selected pregnancy exposures in the National Birth Defects Prevention Study (NBDPS).

METHODS

We analyzed data from the NBDPS, a multi-site case-control study of major birth defects, for mothers of live-born infants without birth defects (controls), with an expected date of delivery (EDD) from 1998 to 2011. Mothers from the 10 participating centers across the United States were interviewed by phone between 6 weeks and 2 years after the EDD. We focused on maternal race/ethnicity and five maternal risk factors: obesity, use of folic acid-containing multivitamins, opioid analgesics, selective serotonin reuptake inhibitors, and loratadine because of their prevalence of use and some reports of associations with major birth defects. Prevalence time trends were examined using the Kendall's τβ test statistic.

RESULTS

The exposure trend analysis included 11,724 control mothers with EDDs from 1998 to 2011. We observed a significant increase in obesity prevalence among control mothers, as well as use of selective serotonin reuptake inhibitors and loratadine. We also observed an increase in periconceptional use of folic acid-containing multivitamins. Some of the time trends varied by race/ethnicity. No remarkable trend in the overall use of opioid analgesics was observed. The racial/ethnic distribution of mothers changed slightly during the study period.

CONCLUSION

Long-term, population-based case-control studies continue to be an effective way to assess exposure-birth defects associations and provide guidance to health care providers. However, investigators examining rare outcomes covering many years of data collection need to be cognizant of time trends in exposures.

Self-reported maternal cigarette smoke exposure during the periconceptional period and the risk for omphalocoele

BACKGROUND

We investigated whether maternal exposure to cigarette smoke was associated with omphalocoele and whether periconceptional folic acid modified the association.

METHODS

 : We analysed data from the National Birth Defects Prevention Study on omphalocoele case (n = 301) and control (n = 8135) mothers for infants born from 1997 through 2007. Mothers who reported active smoking or exposure to second-hand smoke during the periconceptional period (1 month before conception to 3 months after) were considered exposed. Those who reported use of folic acid supplements during the same period were considered supplement users. Odds ratios and 95% confidence intervals were estimated using multivariable logistic regression adjusted for alcohol use, preconception body mass index, and race/ethnicity.

RESULTS

One hundred fifteen (38.2%) case and 2592 (31.9%) control mothers reported exposure to cigarette smoke during the periconceptional period. Adjusted odds ratios [95% confidence intervals] were 1.19 [0.94, 1.53] for any smoke exposure, 0.87 [0.54, 1.40] for active smoking, 1.38 [1.00, 1.90] for second-hand smoke exposure, and 1.16 [0.80, 1.67] for both exposures combined. No dose-response relationship was observed. Folic acid-containing supplements did not reduce the risk for omphalocoele among women with active or second-hand smoke exposure.

CONCLUSIONS

Self-reported active maternal smoking, with or without exposure to second-hand smoke, during the periconceptional period was not associated with omphalocoele. In contrast, there was a possible association with periconceptional exposure to second-hand smoke.

The Janus face of caffeine

Caffeine is certainly the psychostimulant substance most consumed worldwide. Over the past years, chronic consumption of caffeine has been associated with prevention of cognitive decline associated to aging and mnemonic deficits of brain disorders. While its preventive effects have been reported extensively, the cognitive enhancer properties of caffeine are relatively under debate. Surprisingly, there are scarce detailed ontogenetic studies focusing on neurochemical parameters related to the effects of caffeine during prenatal and earlier postnatal periods. Furthermore, despite the large number of epidemiological studies, it remains unclear how safe is caffeine consumption during pregnancy and brain development. Thus, the purpose of this article is to review what is currently known about the actions of caffeine intake on neurobehavioral and adenosinergic system during brain development. We also reviewed other neurochemical systems affected by caffeine, but not only during brain development. Besides, some recent epidemiological studies were also outlined with the control of "pregnancy signal" as confounding variable. The idea is to tease out how studies on the impact of caffeine consumption during brain development deserve more attention and further investigation.

Alcohol use in pregnancy: insights in screening and intervention for the clinician

Alcohol consumption during pregnancy remains a common occurrence and is associated with a multitude of adverse birth and long-term outcomes. Binge drinking in particular is shown to be particularly harmful to the developing fetus. Effects include full fetal alcohol syndrome, with characteristic facial dysmorphology, growth restriction, and developmental to delays. Exposed children may also have partial fetal alcohol syndrome, alcohol-related birth defects, and alcohol-related neurodevelopmental disorders. These effects are preventable, and efforts must begin with accurate identification of women who consume alcohol during pregnancy. Several screening tools have been developed and validated for use in prenatal care settings, and the most recently proposed brief and easy to use T-ACER3 has demonstrated high sensitivity and specificity in both identifying risk drinking during pregnancy and predicting long-term neurobehavioral outcomes in exposed children. Once identified, effective interventions are available for use with pregnant women consuming alcohol. Brief interventions, which can be delivered by a health professional and involve motivational interviewing, have been demonstrated to significantly reduce alcohol consumption during pregnancy. These approaches, recommended by American College of Obstetricians and Gynecologist (ACOG), help move patients toward increased readiness to positively change their drinking behavior. Ultimately, all prenatal care providers should routinely screen all patients for alcohol use using validated tools, and where appropriate, should offer intervention.

Alcohol exposure during late ovine gestation alters fetal liver iron homeostasis without apparent dysmorphology

High levels of alcohol (ethanol) exposure during fetal life can affect liver development and can increase susceptibility to infection after birth. Our aim was to determine the effects of a moderate level of ethanol exposure in late gestation on the morphology, iron status, and inflammatory status of the ovine fetal liver. Pregnant ewes were chronically catheterized at 91 days of gestation (DG; term ∼145 DG) for daily intravenous infusion of ethanol (0.75 g/kg maternal body wt; n = 8) or saline ( n = 7) over 1 h from 95 to 133 DG. At necropsy (134 DG), fetal livers were collected for analysis. Liver weight, general liver morphology, hepatic cell proliferation and apoptosis, perivascular collagen deposition, and interleukin ( IL) -1β, IL-6, or IL-8 mRNA levels were not different between groups. However, ethanol exposure led to significant decreases in hepatic content of ferric iron and gene expression of the iron-regulating hormone hepcidin and tumor necrosis factor ( TNF) -α (all P < 0.05). In the placenta, there was no difference in transferrin receptor, divalent metal transporter 1, and ferritin mRNA levels; however, ferroportin mRNA levels were increased in ethanol-exposed animals ( P < 0.05), and ferroportin protein tended to be increased ( P = 0.054). Plasma iron concentration was not different between control and ethanol-exposed groups; control fetuses had significantly higher iron concentrations than their mothers, whereas maternal and fetal iron concentrations were similar in ethanol-exposed animals. We conclude that daily ethanol exposure during the third-trimester-equivalent in sheep does not alter fetal liver morphology; however, decreased fetal liver ferric iron content and altered hepcidin and ferroportin gene expression indicate that iron homeostasis is altered.

Maternal caffeine consumption and risk of congenital limb deficiencies

BACKGROUND

Animal studies have shown that high doses of caffeine might cause congenital limb deficiencies (LDs); however, no epidemiologic studies have explored this relation.

METHODS

This case-control study assessed associations between maternal dietary caffeine and congenital LDs using data from the National Birth Defects Prevention Study (NBDPS), with 844 LD cases and 8069 controls from 1997 to 2007. Caffeine intakes from beverages (coffee, tea, and soda) and chocolate combined and by beverage type were examined. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated for subtypes of isolated LDs (no additional major anomalies) and LDs with other major anomalies separately, comparing the odds of 10 to <100, 100 to <200, 200 to <300, and 300+ mg/day total caffeine intake to 0 to <10 mg/day.

RESULTS

All total dietary caffeine intake categories of 10 mg/day and above were marginally associated with odds of all isolated LDs combined (aOR, 1.4-1.7), isolated longitudinal LDs (aOR, 1.2-1.6), and isolated transverse LDs (aOR, 1.3-1.8) compared to the lowest intake category. A dose-response pattern for total dietary caffeine intake was not observed.

CONCLUSIONS

A weak increased risk of congenital LDs associated with maternal dietary caffeine consumption was observed in this study; however, risk did not vary by amount of caffeine consumed.

Phenotype severity in the bladder exstrophy-epispadias complex: analysis of genetic and nongenetic contributing factors in 441 families from North America and Europe

OBJECTIVE

To identify genetic and nongenetic risk factors that contribute to the severity of the bladder exstrophy-epispadias complex (BEEC).

STUDY DESIGN

Patients with BEEC from North America (n = 167) and Europe (n = 274) were included. The following data were collected: associated anomalies, parental age at conception, mode of conception, periconceptional folic acid supplementation, maternal risk factors during pregnancy, and environmental risk factors. The patients were divided into 3 subgroups according to phenotype severity: (i) mild, epispadias (n = 43); (ii) intermediate, classic bladder exstrophy (n = 366); and (iii) severe, cloacal exstrophy (n = 31). These subgroups then were compared with identify factors that contribute to phenotype severity.

RESULTS

Males were overrepresented in all subgroups. A relatively high prevalence of cleft lip, with or without cleft palate, was observed. Maternal smoking and medical radiation during the first trimester were associated with the severe cloacal exstrophy phenotype. Compliance with periconceptional folic acid supplementation was associated with the mildest phenotype (epispadias).

CONCLUSIONS

Periconceptional folic acid supplementation appears to prevent the development of the severe phenotype of BEEC.

Maternal smoking in pregnancy and birth defects: a systematic review based on 173 687 malformed cases and 11.7 million controls

BACKGROUND

There is uncertainty over whether maternal smoking is associated with birth defects. We conducted the first ever comprehensive systematic review to establish which specific malformations are associated with smoking.

METHODS

Observational studies published 1959–2010 were identified (Medline), and included if they reported the odds ratio (OR) for having a non-chromosomal birth defect among women who smoked during pregnancy compared with non-smokers. ORs adjusted for potential confounders were extracted (e.g. maternal age and alcohol), otherwise unadjusted estimates were used. One hundred and seventy-two articles were used in the meta-analyses: a total of 173 687 malformed cases and 11 674 332 unaffected controls.

RESULTS

Significant positive associations with maternal smoking were found for: cardiovascular/heart defects [OR 1.09, 95% confidence interval (CI) 1.02–1.17]; musculoskeletal defects (OR 1.16, 95% CI 1.05–1.27); limb reduction defects (OR 1.26, 95% CI 1.15–1.39); missing/extra digits (OR 1.18, 95% CI 0.99–1.41); clubfoot (OR 1.28, 95% CI 1.10–1.47); craniosynostosis (OR 1.33, 95% CI 1.03–1.73); facial defects (OR 1.19, 95% CI 1.06–1.35); eye defects (OR 1.25, 95% CI 1.11–1.40); orofacial clefts (OR 1.28, 95% CI 1.20–1.36); gastrointestinal defects (OR 1.27, 95% CI 1.18–1.36); gastroschisis (OR 1.50, 95% CI 1.28–1.76); anal atresia (OR 1.20, 95% CI 1.06–1.36); hernia (OR 1.40, 95% CI 1.23–1.59); and undescended testes (OR 1.13, 95% CI 1.02–1.25). There was a reduced risk for hypospadias (OR 0.90, 95% CI 0.85–0.95) and skin defects (OR 0.82, 0.75–0.89). For all defects combined the OR was 1.01 (0.96–1.07), due to including defects with a reduced risk and those with no association (including chromosomal defects).

CONCLUSIONS

Birth defects that are positively associated with maternal smoking should now be included in public health educational materials to encourage more women to quit before or during pregnancy.

Evaluation of the reproductive and developmental risks of caffeine

A risk analysis of in utero caffeine exposure is presented utilizing epidemiological studies and animal studies dealing with congenital malformation, pregnancy loss, and weight reduction. These effects are of interest to teratologists, because animal studies are useful in their evaluation. Many of the epidemiology studies did not evaluate the impact of the "pregnancy signal," which identifies healthy pregnancies and permits investigators to identify subjects with low pregnancy risks. The spontaneous abortion epidemiology studies were inconsistent and the majority did not consider the confounding introduced by not considering the pregnancy signal. The animal studies do not support the concept that caffeine is an abortafacient for the wide range of human caffeine exposures. Almost all the congenital malformation epidemiology studies were negative. Animal pharmacokinetic studies indicate that the teratogenic plasma level of caffeine has to reach or exceed 60 µg/ml, which is not attainable from ingesting large amounts of caffeine in foods and beverages. No epidemiological study described the "caffeine teratogenic syndrome." Six of the 17 recent epidemiology studies dealing with the risk of caffeine and fetal weight reduction were negative. Seven of the positive studies had growth reductions that were clinically insignificant and none of the studies cited the animal literature. Analysis of caffeine's reproductive toxicity considers reproducibility and plausibility of clinical, epidemiological, and animal data. Moderate or even high amounts of beverages and foods containing caffeine do not increase the risks of congenital malformations, miscarriage or growth retardation. Pharmacokinetic studies markedly improve the ability to perform the risk analyses.

Maternal caffeine intake and risk of selected birth defects in the National Birth Defects Prevention Study

BACKGROUND

Caffeine intake is common during pregnancy, yet few epidemiologic studies have examined the association between maternal caffeine consumption and birth defects. Using data from the National Birth Defects Prevention Study (NBDPS), we examined the association between maternal caffeine consumption and anotia/microtia, esophageal atresia, small intestinal atresia, craniosynostosis, diaphragmatic hernia, omphalocele, and gastroschisis.

METHODS

The NBDPS is a multi-site population-based case-control study. The present analysis included 3,346 case infants and 6,642 control infants born from October 1997 through December 2005. Maternal telephone interview reports of demographic characteristics and conditions and exposures before and during pregnancy were collected. Odds ratios and 95% confidence intervals, adjusted for relevant covariates, were calculated to estimate the associations between maternal dietary caffeine intake (coffee, tea, soda, and chocolate) and maternal use of caffeine-containing medications and each defect.

RESULTS

We observed small, statistically significant elevations in adjusted odds ratios ranging from 1.3 to 1.8 for total maternal dietary caffeine intake or specific types of caffeinated beverages and anotia/microtia, esophageal atresia, small intestinal atresia, and craniosynostosis; however, dose-response patterns were absent. Periconceptional use of caffeine-containing medications was infrequent and estimates were imprecise.

CONCLUSIONS

We did not find convincing evidence of an association between maternal caffeine intake and the birth defects included in this study. The increasing popularity of caffeine-containing energy drinks and other caffeinated products may result in higher caffeine intake among women of childbearing age. Future studies should consider more detailed evaluation of such products.

Caffeine, selected metabolic gene variants, and risk for neural tube defects

BACKGROUND

Investigations of maternal caffeine intake and neural tube defects (NTDs) have not considered genetic influences. Caffeine metabolism gene effects were examined in the National Birth Defects Prevention Study.

METHODS

Average daily caffeine was summed from self-reported coffee, tea, soda, and chocolate intake for mothers of 768 NTD cases, and 4143 controls delivered from 1997 to 2002. A subset of 306 NTD and 669 control infants and their parents were genotyped for CYP1A2*1F, NAT2 481C>T, and NAT2 590G>A. CYP1A2*1F was classified by fast or slow oxidation status, and NAT2 variants were categorized into rapid or slow acetylation status. Case-control logistic regression analyses, family-based transmission/disequilibrium tests and log-linear analyses, and hybrid log-linear analyses were conducted to produce odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs) for caffeine intake and maternal and infant gene variants, and to examine interaction effects.

RESULTS

NTDs were independently associated with infant slow NAT2 acetylator status (RR, 2.00; 95% CI, 1.10-3.64) and maternal CYP1A2*1F fast oxidation status (OR, 1.49; 95% CI, 1.10-2.03). Mothers who consumed caffeine, oxidized CYP1A2*1F quickly, and acetylized NAT2 slowly had a nonsignificantly elevated estimated risk for an NTD-affected pregnancy (OR, 3.10; 95% CI, 0.86-11.21). Multiplicative interaction effects were observed between maternal caffeine and infant CYP1A2*1F fast oxidizer status (p(interaction) = 0.03).

CONCLUSIONS

The association identified between maternal CYP1A2*1F fast oxidation status and NTDs should be examined further in the context of the other substrates of CYP1A2. Maternal caffeine and its metabolites may be associated with increased risk for NTD-affected pregnancies in genetically susceptible subgroups.

Time of birth and risk of neonatal death at term: retrospective cohort study

OBJECTIVE

To determine the effect of time and day of birth on the risk of neonatal death at term.

DESIGN

Population based retrospective cohort study.

SETTING

Data from the linked Scottish morbidity records, Stillbirth and Infant Death Survey, and birth certificate database of live births in Scotland, 1985-2004.

SUBJECTS

Liveborn term singletons with cephalic presentation. Perinatal deaths from congenital anomalies excluded. Final sample comprised 1,039,560 live births.

MAIN OUTCOME MEASURE

All neonatal deaths (in the first four weeks of life) unrelated to congenital abnormality, plus a subgroup of deaths ascribed to intrapartum anoxia.

RESULTS

The risk of neonatal death was 4.2 per 10,000 during the normal working week (Monday to Friday, 0900-1700) and 5.6 per 10 000 at all other times (out of hours) (unadjusted odds ratio 1.3, 95% confidence interval 1.1 to 1.6). Adjustment for maternal characteristics had no material effect. The higher rate of death out of hours was because of an increased risk of death ascribed to intrapartum anoxia (adjusted odds ratio 1.7, 1.2 to 2.3). Though exclusion of elective caesarean deliveries attenuated the association between death ascribed to anoxia and delivery out of hours, a significant association persisted (adjusted odds ratio 1.5, 1.1 to 2.0). The attributable fraction of neonatal deaths ascribed to intrapartum anoxia associated with delivery out of hours was 26% (95% confidence interval 5% to 42%).

CONCLUSIONS

Delivering an infant outside the normal working week was associated with an increased risk of neonatal death at term ascribed to intrapartum anoxia.

A review of the epidemiologic evidence concerning the reproductive health effects of caffeine consumption: a 2000-2009 update

This review of human studies of caffeine and reproductive health published between January 2000 and December 2009 serves to update the comprehensive review published by Leviton and Cowan (2002). The adverse reproductive outcomes addressed in this review include: (1) measures of subfecundity; (2) spontaneous abortion; (3) fetal death; (4) preterm birth; (5) congenital malformations; and (6) fetal growth restriction. Methodologic challenges and considerations relevant to investigations of each reproductive endpoint are summarized, followed by a brief critical review of each study. The evidence for an effect of caffeine on reproductive health and fetal development is limited by the inability to rule out plausible alternative explanations for the observed associations, namely confounding by pregnancy symptoms and smoking, and by exposure measurement error. Because of these limitations, the weight of evidence does not support a positive relationship between caffeine consumption and adverse reproductive or perinatal outcomes.

Environmental exposures and development

PURPOSE OF REVIEW

Summarize recent studies exploring the relationship between paternal and maternal environmental exposures to chemicals before, at the time of and after conception to adverse developmental outcomes including preterm birth, death, structural and functional abnormalities and growth restriction.

RECENT FINDINGS

Recent studies have demonstrated that human pregnancy and development are vulnerable to environmental exposures of the father and mother to chemical, biological and physical agents. Exposures associated with adverse developmental outcomes include air and water pollution, chemicals in foods, occupational exposures, agricultural chemicals, metals, persistent and volatile organics. Developmental endpoints which are linked with these exposures include growth restriction, functional abnormalities, structural abnormalities, preterm delivery and death. Despite this general understanding we still have incomplete knowledge concerning most exposures and the biological interactions responsible for impaired development and preterm delivery.

SUMMARY

Whereas single genes and individual chemical exposures are responsible for some instances of adverse pregnancy outcome or developmental disease, gene-environment interactions are responsible for the majority. These gene-environment interactions may occur in the father, mother, placenta or fetus, suggesting that critical attention be given to maternal and paternal exposures and gene expression as they relate to the mode of action of the putative developmental toxicant both prior to and during pregnancy.

Alcohol abuse in pregnant women: effects on the fetus and newborn, mode of action and maternal treatment

Offspring of mothers using ethanol during pregnancy are known to suffer from developmental delays and/or a variety of behavioral changes. Ethanol, may affect the developing fetus in a dose dependent manner. With very high repetitive doses there is a 6-10% chance of the fetus developing the fetal alcoholic syndrome manifested by prenatal and postnatal growth deficiency, specific craniofacial dysmorphic features, mental retardation, behavioral changes and a variety of major anomalies. With lower repetitive doses there is a risk of "alcoholic effects" mainly manifested by slight intellectual impairment, growth disturbances and behavioral changes. Binge drinking may impose some danger of slight intellectual deficiency. It is advised to offer maternal abstinence programs prior to pregnancy, but they may also be initiated during pregnancy with accompanying close medical care. The long term intellectual outcome of children born to ethanol dependent mothers is influenced to a large extent by the environment in which the exposed child is raised.