Adverse fetal/neonatal and obstetric outcomes in pregnancies with both maternal and fetal heart disease

OBJECTIVE

To investigate fetal/neonatal and obstetric events in pregnancies with both maternal and fetal heart disease.

STUDY DESIGN

From the CARPREG database, singleton pregnancies (>24 weeks) in patients with structural heart disease that underwent fetal/neonatal echocardiograms were selected and separated in two groups: maternal heart disease only (M-HD) and maternal and fetal heart disease (MF-HD). Differences in adverse fetal/neonatal (death, preterm birth, and small for gestational age) and obstetric (preeclampsia/eclampsia) outcomes between groups were analyzed.

RESULTS

From 1011 pregnancies, 93 had MF-HD. Fetal/neonatal events (38.7% vs 25.3%, p = 0.006) and spontaneous preterm birth (10.8% vs 4.9%, p = 0.021) were more frequent in MF-HD compared to M-HD, with no difference in obstetric events. MF-HD remained as a significant predictor of fetal/neonatal events after adjustment (OR:1.883; 95% CI:1.182-3.000; p = 0.008).

CONCLUSIONS

Pregnancies with MF-HD are at risk of adverse fetal/neonatal events and spontaneous preterm birth. Larger studies are needed to determine their association with preeclampsia.

Association between First Trimester Exposure to Ambient PM2.5 and NO2 and Congenital Heart Defects: A Population-Based Cohort Study of 1,342,198 Live Births in Canada

BACKGROUND

The extent to which ambient air pollution contributes to the pathogenesis of congenital heart defects remains uncertain.

OBJECTIVE

We investigated whether first trimester exposure to ambient fine particulate matter (PM2.5) and nitrogen dioxide (NO2) was associated with the risk of critical and noncritical heart defects in a large population-based cohort of births.

METHODS

We carried out a retrospective cohort study of children conceived between 2000 and 2016 in Quebec, Canada. Heart defects were identified via data from the Maintenance and Use of Data for the Study of Hospital Clientele registry. The main exposures were average concentration of PM2.5 and NO2 in a) the first trimester and b) the month of conception. Exposures were estimated at the residential postal code. Associations with critical and noncritical heart defects were assessed using logistic regression models, adjusted for maternal and infant characteristics. We considered single- and two-pollutant models and assessed modifying effects of maternal comorbidity, including preexisting hypertension, preeclampsia, anemia, and diabetes.

RESULTS

The cohort comprised 1,342,198 newborns, including 12,715 with heart defects. Exposure in the first trimester and month of conception yielded similar results; both were associated with a greater risk of heart defects. Adjusted odds ratios (OR) for any heart defect per interquartile range increase were 1.02 (95% CI: 1.00, 1.05) for PM2.5 and 1.10 (95% CI: 1.07, 1.13) for NO2. Associations with atrial septal defects were 1.08 (95% CI: 1.03, 1.14) for PM2.5 and 1.19 (95% CI: 1.12, 1.25) for NO2. Corresponding ORs for ventricular septal defects and individual critical heart defects were not significant. PM2.5 (OR=1.11; 95% CI: 1.06, 1.17) and NO2 (OR=1.23; 95% CI: 1.17, 1.31) exposure were associated with a greater risk of heart defects in mothers with comorbidity.

DISCUSSION

In this population-based cohort, prenatal exposure to ambient air pollution during the first trimester was associated with an increased risk of heart defects, particularly atrial septal defects. The association with heart defects was greater in mothers with comorbidity. https://doi.org/10.1289/EHP11120.

Assessing associations between residential proximity to greenspace and birth defects in the National Birth Defects Prevention Study

BACKGROUND

Residential proximity to greenspace is associated with various health outcomes.

OBJECTIVES

We estimated associations between maternal residential proximity to greenspace (based on an index of vegetation) and selected structural birth defects, including effect modification by neighborhood-level factors.

METHODS

Data were from the National Birth Defects Prevention Study (1997-2011) and included 19,065 infants with at least one eligible birth defect (cases) and 8925 without birth defects (controls) from eight Centers throughout the United States. Maternal participants reported their addresses throughout pregnancy. Each address was systematically geocoded and residences around conception were linked to greenspace, US Census, and US Department of Agriculture data. Greenspace was estimated using the normalized difference vegetation index (NDVI); average maximum NDVI was estimated within 100 m and 500 m concentric buffers surrounding geocoded addresses to estimate residential NDVI. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals comparing those in the highest and lowest quartiles of residential NDVI and stratifying by rural/urban residence and neighborhood median income.

RESULTS

After multivariable adjustment, for the 500 m buffer, inverse associations were observed for tetralogy of Fallot, secundum atrial septal defects, anencephaly, anotia/microtia, cleft lip ± cleft palate, transverse limb deficiency, and omphalocele, (aORs: 0.54-0.86). Results were similar for 100 m buffer analyses and similar patterns were observed for other defects, though results were not significant. Significant heterogeneity was observed after stratification by rural/urban for hypoplastic left heart, coarctation of the aorta, and cleft palate, with inverse associations only among participants residing in rural areas. Stratification by median income showed heterogeneity for atrioventricular and secundum atrial septal defects, anencephaly, and anorectal atresia, with inverse associations only among participants residing in a high-income neighborhood (aORs: 0.45-0.81).

DISCUSSION

Our results suggest that perinatal residential proximity to more greenspace may contribute to a reduced risk of certain birth defects, especially among those living in rural or high-income neighborhoods.

Pre-eclampsia is associated with increased neurodevelopmental disorders in children with congenital heart disease

AIMS

Our primary aim was to examine whether exposure to pre-eclampsia increases the risk of neurodevelopmental disorders in children born with congenital heart disease (CHD). Our secondary aim was to evaluate whether CHD and pre-eclampsia may act in synergy and potentiate this risk.

METHOD AND RESULTS

Using population-based registries, we included all Danish children born with CHD between 1994 and 2017. Non-singletons and children born with a syndrome were excluded. Neurodevelopmental disorders including attention-deficit/hyperactivity disorder, autism spectrum disorders, and tic disorders were identified with the use of the 10th edition of International Classification of Disease (ICD-10) codes DF80-DF98. Using Cox proportional hazard regression, we estimated the risk of neurodevelopmental disorders in children with CHD exposed to pre-eclampsia compared with those with CHD not exposed to pre-eclampsia. The population consisted of 11 449 children born with CHD. Children exposed to pre-eclampsia had an increased risk of neurodevelopmental disorders, hazard ratio: 1.84 (95% confidence interval: 1.39-2.42). Furthermore, a comparison cohort of 113 713 children with no CHD diagnoses were included. Using cumulative incidence analyses with death as competing risk, we compared the risk of neurodevelopmental disorders if exposed to pre-eclampsia among children with CHD and children without CHD. Exposure to pre-eclampsia drastically increased the cumulative incidence of neurodevelopmental disorders in children born with CHD.

CONCLUSION

Exposure to pre-eclampsia is associated with increased risk of neurodevelopmental disorders in children born with CHD. CHD and pre-eclampsia may act in synergy and potentiate this effect. Clinicians should therefore be especially attentive to neurodevelopmental problems in this vulnerable subgroup.

Hypertensive Disorders in Pregnancy Are Associated With Congenital Heart Defects in Offspring: A Systematic Review and Meta-Analysis

Background

Although research indicates an association between hypertensive disorders of pregnancy (HDP) and congenital heart defects (CHDs) in offspring, consistency is still lacking. Therefore, we aimed to synthesize the updated published epidemiologic evidence to estimate the association of maternal HDP with the risk of total CHDs and its phenotypes in offspring.

Methods

A systematic search of Web of Science Database, PubMed, and Embase were searched from inception through April 30, 2021 based on a preprepared protocol, and the reference lists were also manually searched. The combined risk estimates were calculated using either the fixed-effect models or random-effect models. Possible heterogeneity moderators were detected by subgroup, sensitivity analyses, and Galbraith plot.

Results

Twenty-four studies involving 477,839 CHDs cases among 40,394,699 participants were included in our meta-analysis. Mothers who had HDP exposure were significantly associated with an increased risk of total CHDs compared with non-exposure. When maternal HDP exposure was further subdivided into pre-eclampsia (OR = 1.79, 95% CI: 1.50–2.13), gestational hypertension (OR = 1.16, 95% CI: 1.02–1.31), and chronic hypertension (OR = 1.68, 95% CI: 1.49–1.89), a significantly increased risk of total CHDs were still presented. Furthermore, a statistically significant increased association was found between maternal HDP exposure and most CHD phenotypes. Besides, relevant heterogeneity moderators have been identified by subgroup and sensitivity analyses.

Conclusion

Our study suggested that maternal HDP exposure may be associated with an increase in the risk of CHDs in offspring. These findings highlight the need for greater surveillance of pregnant women with HDP exposure to allow early prevention that may be good for reducing the risk of CHDs in offspring.

Clinical Trial Registration

[www.ClinicalTrials.gov], identifier [CRD42021268093].

Impact of Maternal-Fetal Environment on Mortality in Children With Single Ventricle Heart Disease

BACKGROUND

Children with single ventricle heart disease have significant morbidity and mortality. The maternal–fetal environment (MFE) may adversely impact outcomes after neonatal cardiac surgery. We hypothesized that impaired MFE would be associated with an increased risk of death after stage 1 Norwood reconstruction.

METHODS AND RESULTS

We performed a retrospective cohort study of children with hypoplastic left heart syndrome (and anatomic variants) who underwent stage 1 Norwood reconstruction between 2008 and 2018. Impaired MFE was defined as maternal gestational hypertension, preeclampsia, gestational diabetes, and/or smoking during pregnancy. Cox proportional hazards regression models were used to investigate the association between impaired MFE and death while adjusting for confounders. Hospital length of stay was assessed with the competing risk of in‐hospital death. In 273 children, the median age at stage 1 Norwood reconstruction was 4 days (interquartile range [IQR], 3–6 days). A total of 72 children (26%) were exposed to an impaired MFE; they had more preterm births (18% versus 7%) and a greater percentage with low birth weights <2.5 kg (18% versus 4%) than those without impaired MFE. Impaired MFE was associated with a higher risk of death (hazard ratio [HR], 6.05; 95% CI, 3.59–10.21; P<0.001) after adjusting for age at surgery, Hispanic ethnicity, genetic syndrome, cardiac diagnosis, surgeon, and birth era. Children with impaired MFE had almost double the risk of prolonged hospital stay (HR, 1.95; 95% CI, 1.41–2.70; P<0.001).

CONCLUSIONS

Children exposed to an impaired MFE had a higher risk of death following stage 1 Norwood reconstruction. Prenatal exposures are potentially modifiable factors that can be targeted to improve outcomes after pediatric cardiac surgery.

Preeclampsia and Fetal Congenital Heart Defects

Endothelial dysfunction, impaired implantation and placental insufficiency have been identified as mechanisms behind the development of pre-eclampsia, resulting in angiogenic factors' alteration. Angiogenic imbalance is also associated with congenital heart defects, and this common physiologic pathway may explain the association between them and pre-eclampsia. This review aims to understand the physiology shared by these two entities and whether women with pre-eclampsia have an increased risk of fetal congenital heart defects (or the opposite). The present research has highlighted multiple vasculogenic pathways associated with heart defects and preeclampsia, but also epigenetic and environmental factors, contributing both. It is also known that fetuses with a prenatal diagnosis of congenital heart disease have an increased risk of several comorbidities, including intrauterine growth restriction. Moreover, the impact of pre-eclampsia goes beyond pregnancy as it increases the risk for following pregnancies and for diseases later in life in both offspring and mothers. Given the morbidity and mortality associated with these conditions, it is of foremost importance to understand how they are related and its causative mechanisms. This knowledge may allow earlier diagnosis, an adequate surveillance or even the implementation of preventive strategies.

Population-based study on birth outcomes among women with hypertensive disorders of pregnancy and gestational diabetes mellitus

To evaluate birth outcomes in women with hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM), we used insurance data of Taiwan to evaluate 11 adverse neonatal outcomes of infants born to women with HDP (N = 7775) and with both HDP and GDM (HDP/GDM) (N = 1946), comparing to women with neither disorder (N = 19,442), matched by age. The impacts of preeclampsia/eclampsia were also evaluated. Results showed that Caesarean section delivery was near 1.7-fold greater in the HDP/GDM and HDP groups than in comparisons. The preterm delivery rates were more than threefold greater in HDP/GDM group and HDP group than in comparisons with adjusted odds ratios (aORs) of 4.84 (95% confidence interval (CI) 4.34–5.40) and 3.92 (95% CI 3.65–4.21), respectively, followed by jaundice (aORs 2.95 (95% CI 2.63–3.33) and 1.90 (95% CI 1.76–2.06)), and small gestation age (SGA) (aORs 6.57 (95% CI 5.56–7.75) and 5.81 (95% CI 5.15–6.55)). Incidence rates of birth trauma, patent ductus arteriosus, atrial septal defect, respiratory distress syndrome, and neonatal hypoglycemia were also higher in the HDP/GDM and HDP groups than in the comparison group. Most adverse outcomes increased further in women with preeclampsia or eclampsia. In conclusion, women with HDP are at elevated risks of adverse neonatal outcomes. Risks of most adverse outcomes increase further for women with both HDP and GDM. Preeclampsia or eclampsia may also contribute to these outcomes to higher risk levels. Every pregnant woman with these conditions deserves specialized prenatal care.

The placenta as the window to congenital heart disease

PURPOSE OF REVIEW

There is an increasing recognition that structural abnormalities and functional changes in the placenta can have deleterious effects on the development of the fetal heart. This article reviews the role of the placenta and the potential impact of placental insufficiency on fetuses with congenital heart disease.

RECENT FINDINGS

The fetal heart and the placenta are directly linked because they develop concurrently with shared regulatory and signaling pathways. Placental disease is more common in pregnancies carrying a fetus with congenital heart disease and the fetal response to placental insufficiency may lead to the postnatal persistence of cardiac remodeling. The mechanisms underlying this placental-fetal axis of interaction potentially include genetic factors, oxidative stress, chronic hypoxia, and/or angiogenic imbalance.

SUMMARY

The maternal-placental-fetal circulation is critical to advancing our understanding of congenital heart disease. We must first expand our ability to detect, image, and quantify placental insufficiency and dysfunction in utero. Elucidating the modifiable factors involved in these pathways is an exciting opportunity for future research, which may enable us to improve outcomes in patients with congenital heart disease.

Association of abnormal placental perfusion with the risk of male hypospadias: a hospital-based retrospective cohort study

BACKGROUND

The effect and extent of abnormal placental perfusion (APP) on the risk of male hypospadias are poorly understood. We compared the prevalence of male hypospadias in the offspring of women with APP and quantify the extent of the APP effect on the anomaly.

METHODS

A hospital-based retrospective analysis of births from 2012 to 2016 was conducted in 2018. Women of singleton pregnancy and male infants born to them were included (N = 21,447). A multivariate analysis was performed to compare the prevalence of male hypospadias in infants exposed to APP with those that were not exposed to APP.

RESULTS

Compared with the infants of women without APP, infants of women with APP showed an increased risk of male hypospadias (odds ratio, 2.40; 95% confidence interval, 1.09-5.29). The male hypospadias cumulative risk increased with the severity of APP. Infants exposed to severe APP had a significantly higher risk of male hypospadias than those without APP exposure (9.2 versus 1.7 per 1000 infants, P < 0.001). A path analysis indicated that 28.18-46.61% of the risk of hypospadias may be attributed to the effect of APP.

CONCLUSIONS

Male hypospadias risk was associated with APP and increased with APP severity, as measured in the second trimester. APP had an important role in the development of the anomaly.

THBS1 regulates trophoblast fusion through a CD36-dependent inhibition of cAMP, and its upregulation participates in preeclampsia

Preeclampsia is a pregnancy complication which threatens the survival of mothers and fetuses. It originates from abnormal placentation, especially insufficient fusion of the cytotrophoblast cells to form the syncytiotrophoblast. In this study, we found that THBS1, a matricellular protein that mediates cell-to-cell and cell-to-matrix interactions, is downregulated during the fusion of primary cytotrophoblast and BeWo cells, but upregulated in the placenta of pregnancies complicated by preeclampsia. Also, THBS1 was observed to interact with CD36, a membrane signal receptor and activator of the cAMP signaling pathway, to regulate the fusion of cytotrophoblast cells. Overexpression of THBS1 inhibited the cAMP signaling pathway and reduced the BeWo cells fusion ratio, while the effects of THBS1 were abolished by a CD36-blocking antibody. Our results suggest that THBS1 signals through a CD36-mediated cAMP pathway to regulate syncytialization of the cytotrophoblast cells, and that its upregulation impairs placental formation to cause preeclampsia. Thus, THBS1 can serve as a therapeutic target regarding the mitigation of abnormal syncytialization and preeclampsia.

Profile of congenital heart disease in infants born following exposure to preeclampsia

BACKGROUND

Events in pregnancy play an important role in predisposing the newborn to the risk of developing CHD. This study evaluated the association between maternal preeclampsia and her offspring risk of CHD.

METHODS

This is a cohort study of 90 sex-matched neonates (45 each born to women with preeclampsia and normal pregnancy) in Jos, Nigeria. Anthropometry was taken shortly after delivery using standard protocols. Echocardiography was performed within 24 hours of life and repeated 7 and 28 days later. SPSS version 25 was used in all analyses. Statistical significance was set at p<0.05.

RESULTS

Congenital heart disease (CHD) was observed in 27 (30.0%) of newborns of women with preeclampsia compared with 11 (12.1%) of newborns without preeclampsia (p<0.001) at the end of 7 days and in 19 (21.1%) of newborns of women with preeclampsia and 3 (3.3%) of newborns of women without preeclampsia by the end of the 4th week of life (p<0.001). Overall, ASD (4 newborns), PDA (21 newborns), patent foramen ovale (14 newborns) and VSD (2 newborns) were the prevalent lesions found among all the newborns studied in the first week of life. Isolated atrial and ventricular septal defects were seen in 4 (4.4%) of the newborns of women with preeclampsia. Being the infant of a woman with preeclampsia was associated with about 8-fold increased risk of having CHD (OR = 7.9, 95% CI = 2.5-24.9, p<0.001).

CONCLUSION

CHD may be more common in newborns of women with preeclampsia underscoring the need for fetal and newborn screening for CHD in women with preeclampsia so as to improve their infant's well being.

Pregnancy outcome in women with atrial septal defect: associated with in vitro fertilisation and pre-eclampsia

Objective

To investigate in vitro fertilisation (IVF) in women with atrial septal defect (ASD), and to examine the maternal characteristics and outcome of pregnancy, as well as the fetal outcome of infants born by women with ASD.

Methods

We used population-based registries in this nationwide cohort study, including Danish individuals born before 1994 who received an ASD diagnosis between 1959 and 2014. Patients were compared with a random reference sample (ratio of 10 citizens per patient) matched by sex and age. The Danish Medical Birth Register (DMBR) contains data on all pregnancies and births in Denmark from 1977 to present. Risk of IVF treatment as well as maternal, pregnancy and fetal outcomes were compared.

Results

A total of 2277 Danish patients had a validated ASD diagnosis. Of these, 310 women were identified in the DMBR. Women with ASD had an increased risk of receiving IVF treatment (HR 3.14, 95% CI 2.1 to 4.7, p<0.0001), and a higher proportion of patients received IVF treatment when compared with the reference cohort (10.6% vs 3.2%; p<0.001). Furthermore, patients had more multiple births. Looking at singleton pregnancies (n=519), pre-eclampsia occurred more frequently in patients with ASD during pregnancy (6.7% vs 2.3%; p<0.001). Infants from mothers with ASD were found to have perinatal outcomes comparable to those of infants from the reference group.

Conclusion

Women with ASD had an increased risk of and received more IVF treatment than the reference group. The outcome of pregnancy in these patients were generally uneventful, however, we did confirm that pre-eclampsia occurred more frequently.

Oxygen and lack of oxygen in fetal and placental development, feto-placental coupling, and congenital heart defects

Low oxygen concentration (hypoxia) is part of normal embryonic development, yet the situation is complex. Oxygen (O₂ ) is a janus gas with low levels signaling through hypoxia-inducible transcription factor (HIF) that are required for development of fetal and placental vasculature and fetal red blood cells. This results in coupling of fetus and mother around midgestation as a functional feto-placental unit (FPU) for O₂ transport, which is required for continued growth and development of the fetus. Defects in these processes may leave the developing fetus vulnerable to O₂ deprivation or other stressors during this critical midgestational transition when common septal and conotruncal heart defects (CHDs) are likely to arise. Recent human epidemiological and case-control studies support an association between placental dysfunction, manifest as early onset pre-eclampsia (PE) and increased serum bio-markers, and CHD. Animal studies support this association, in particular those using gene inactivation in the mouse. Sophisticated methods for gene inactivation, cell fate mapping, and a quantitative bio-reporter of O₂ concentration support the premise that hypoxic stress at critical stages of development leads to CHD. The secondary heart field contributing to the cardiac outlet is a key target, with activation of the un-folded protein response and abrogation of FGF signaling or precocious activation of a cardiomyocyte transcriptional program for differentiation, suggested as mechanisms. These studies provide a strong foundation for further study of feto-placental coupling and hypoxic stress in the genesis of human CHD.

The impact of the maternal-foetal environment on outcomes of surgery for congenital heart disease in neonates

OBJECTIVES

Pregnancies with congenital heart disease in the foetus have an increased prevalence of pre-eclampsia, small for gestational age and preterm birth, which are evidence of an impaired maternal-foetal environment (MFE).

METHODS

The impact of an impaired MFE, defined as pre-eclampsia, small for gestational age or preterm birth, on outcomes after cardiac surgery was evaluated in neonates (n = 135) enrolled in a study evaluating exposure to environmental toxicants and neuro-developmental outcomes.

RESULTS

The most common diagnoses were transposition of the great arteries (n = 47) and hypoplastic left heart syndrome (n = 43). Impaired MFE was present in 28 of 135 (21%) subjects, with small for gestational age present in 17 (61%) patients. The presence of an impaired MFE was similar for all diagnoses, except transposition of the great arteries (P < 0.006). Postoperative length of stay was shorter for subjects without an impaired MFE (14 vs 38 days, P < 0.001). Hospital mortality was not significantly different with or without impaired MFE (11.7% vs 2.8%, P = 0.104). However, for the entire cohort, survival at 36 months was greater for those without an impaired MFE (96% vs 68%, P = 0.001). For patients with hypoplastic left heart syndrome, survival was also greater for those without an impaired MFE (90% vs 43%, P = 0.007).

CONCLUSIONS

An impaired MFE is common in pregnancies in which the foetus has congenital heart disease. After cardiac surgery in neonates, the presence of an impaired MFE was associated with lower survival at 36 months of age for the entire cohort and for the subgroup with hypoplastic left heart syndrome.

Early-onset preeclampsia predisposes to preclinical diastolic left ventricular dysfunction in the fifth decade of life: An observational study

Background

Systemic inflammation, endothelial dysfunction and deficient vascularization of either uterus or myocardium are mechanistic hallmarks of early-onset preeclampsia and heart failure with preserved ejection fraction (HFpEF). HFpEF is especially prevalent in elderly women and preceded in middle age by preclinical left ventricular (LV) diastolic dysfunction.

To detect if preeclampsia predisposes to HFpEF at later age, echocardiographic indices of LV function and of LV structure and biomarkers of systemic inflammation and of endothelial dysfunction were compared in middle-aged women with a history of early-onset preeclampsia or uncomplicated pregnancy.

Methods and findings

Middle-aged women with a history of early-onset preeclampsia (n = 131) or uncomplicated pregnancy (n = 56) were prospectively recruited 9 to 16 years after pregnancy.

Women with a history of preeclampsia had higher body mass index (p = 0.006), blood pressure (p<0.001) and plasma levels of interleukin-6 (p = 0.005) and soluble intercellular adhesion molecule-1 (sICAM-1) (p = 0.014). They had thicker septal (p = 0.001) and posterior (p = 0.003) LV walls and worse diastolic LV function evident from reduced mean mitral annular lengthening velocity (E’mean; p = 0.007) and higher ratio of early diastolic mitral flow velocity (E) over E’mean (E/E’mean; p<0.001). Differences of sICAM-1, E’mean and E/E’mean remained significant after accounting for BMI and blood pressure.

Conclusions

History of preeclampsia predisposes in middle age to worse LV diastolic function, which could increase the likelihood of later HFpEF development. This predisposition derives not only from persistent cardiovascular risk but may also be caused by persistent endothelial dysfunction hindering adequate vascularization in the uterus during pregnancy and in the myocardium in middle age.

Occurrence of Selected Structural Birth Defects Among Women With Preeclampsia and Other Hypertensive Disorders

To explore a potential association between preeclampsia and selected birth defects, we examined the prevalence of certain birth defects among women with hypertensive disorders including preeclampsia. We analyzed data from 2,499,536 singleton live births in California from 2007 to 2011, including maternal and infant demographics from birth certificates as well as clinical details from delivery hospitalization records. We examined defect groups that were recognizable at birth (e.g., spina bifida and cleft lip). Hypertensive disorders included preexisting hypertension, gestational hypertension, mild preeclampsia, severe preeclampsia/eclampsia, and preeclampsia superimposed on preexisting hypertension. Relative risk values with 95% confidence intervals for each birth defect were calculated by hypertensive group, as well as independent and joint associations of hypertensive and diabetic disorders. Risks of each type of birth defect were higher among offspring of women with hypertensive disorders compared with those without. The risks of birth defects among offspring of women with only a hypertensive disorder were significantly higher than that among women with neither hypertensive nor diabetic disorders (relative risks ranged from 1.37 to 2.77). Risks of birth defects were highest among those born to women with both hypertensive and diabetic disorders compared with those with neither (relative risks ranged from 1.80 to 6.22). These findings support the existence of an association between preeclampsia and certain birth defects and suggest that diabetes may be a contributing factor.

Association Between Fetal Congenital Heart Defects and Maternal Risk of Hypertensive Disorders of Pregnancy in the Same Pregnancy and Across Pregnancies

BACKGROUND

Both pregnant women carrying fetuses with heart defects and women with hypertensive disorders of pregnancy often exhibit angiogenic imbalances, suggesting that the same mechanisms are involved in the pathogenesis of the former and the pathophysiology of the latter. We conducted a register-based cohort study to determine whether offspring congenital heart defects are associated with an increased risk of hypertensive disorders of pregnancy and whether the mechanisms driving any association are primarily maternal or fetal.

METHODS

Among singleton pregnancies without chromosomal abnormalities lasting ≥20 weeks in Denmark from 1978 to 2011 (n= 1 972 857), we identified pregnancies complicated by offspring congenital heart defects or early preterm preeclampsia, late preterm preeclampsia, term preeclampsia, and gestational hypertension. We used polytomous logistic regression to estimate odds ratios (ORs) for associations between offspring congenital heart defects and maternal hypertensive disorders of pregnancy overall and for specific heart defects.

RESULTS

Offspring congenital heart defects were strongly associated with early preterm preeclampsia (OR, 7.00; 95% confidence interval [CI], 6.11-8.03) and late preterm preeclampsia (OR, 2.82; 95% CI, 2.38-3.34) in the same pregnancy and weakly associated with term preeclampsia (OR, 1.16; 95% CI, 1.06-1.27), but they were not associated with gestational hypertension (OR, 1.07; 95% CI, 0.92-1.25). Association strengths were consistent across heart defect types. Offspring congenital heart defects in a previous pregnancy were also strongly associated with preterm preeclampsia in subsequent pregnancies (early preterm preeclampsia: OR, 2.37; 95% CI, 1.68-3.34; late preterm preeclampsia: OR, 2.04; 95% CI, 1.52-2.75) but were only modestly associated with term preeclampsia and not associated with gestational hypertension. Similarly, preterm preeclampsia in a previous pregnancy, but not term preeclampsia or gestational hypertension, was associated with offspring congenital heart defects in later pregnancies (early preterm preeclampsia: OR, 7.91; 95% CI, 6.06-10.3; late preterm preeclampsia: OR, 2.83; 95% CI, 2.11-3.79; term preeclampsia: OR, 0.98; 95% CI, 0.88-1.10; gestational hypertension: OR, 1.13; 95% CI, 0.92-1.38).

CONCLUSIONS

Linked pathophysiological mechanisms may be involved in some congenital heart defects and preterm preeclampsia. The strong associations across pregnancies support a predominantly maternal origin of effect.

The heart of Africa: succeeding against the odds

South Africa and other areas of sub-Saharan Africa have in the past 20 years undergone rapid demographical changes, largely due to urbanisation and changes in lifestyle. This rapid change has led to a marked increase in specific cardiac conditions, such as hypertensive heart disease and coronary artery disease (with the highest prevalence in the middle-aged population), in conjunction with a range of other heart diseases, which are historically common in Africa-eg, rheumatic heart disease, cardiomyopathies, and unoperated congenital heart disease. The short supply of well-equipped screening facilities, late diagnosis, and inadequate care at primary, secondary, and tertiary levels have led to a large burden of patients with poorly treated heart failure. Excellent progress has been made in the understanding of the epidemiology, sociodemographical factors, effect of urbanisation, and pathophysiology of cardiac conditions, such as peripartum cardiomyopathy, rheumatic heart disease, and tuberculous pericarditis, which are common in sub-Saharan Africa. This progress has been achieved largely through several studies, such as the Heart of Soweto, THESUS, REMEDY, BA-HEF, Abeokuta-HF, and the PAPUCO studies. Studies on the suitable therapeutic management of several heart conditions have also been done or are underway. In this Lecture, I provide a personal perspective on the evolving burden of cardiac disease, as witnessed since my appointment at Chris Hani Baragwanath Hospital, in Soweto, South Africa, in 1992, which was also the year that the referendum to end apartheid in South Africa was held. Subsequently, a network of cardiologists was formed under the umbrella of the Heart of Africa Studies and the Pan African Cardiac Society. Furthermore, I summarise the major gaps in the health-care system dealing with the colliding epidemic of communicable and non-communicable heart diseases, including cardiac diseases common in peripartum women. I also touch on the fantastic opportunities available for doing meaningful research with enthusiastic colleagues and, thereby, having a large effect, despite the need to be highly innovative in finding much needed funding support.

Inactivation of maternal Hif-1α at mid-pregnancy causes placental defects and deficits in oxygen delivery to the fetal organs under hypoxic stress

A critical transition occurs near mid-gestation of mammalian pregnancy. Prior to this transition, low concentrations of oxygen (hypoxia) signaling through Hypoxia Inducible Factor (HIF) functions as a morphogen for the placenta and fetal organs. Subsequently, functional coupling of the placenta and fetal cardiovascular system for oxygen (O₂) transport is required to support the continued growth and development of the fetus. Here we tested the hypothesis that Hif-1α is required in maternal cells for placental morphogenesis and function. We used Tamoxifen-inducible Cre-Lox to inactivate Hif-1α in maternal tissues at E8.5 (MATcKO), and used ODD-Luciferase as a reporter of hypoxia in placenta and fetal tissues. MATcKO of Hif-1α reduced the number of uterine natural killer (uNK) cells and Tpbpa-positve trophoblast cells in the maternal decidua at E13.5 -15.5. There were dynamic changes in all three layers of E13.5-15.5 MATcKO placenta. Of note was the under-development of the labyrinth at E15.5 associated with reduced Ki67 and increased TUNEL staining consistent with reduced cell proliferation and increased apoptosis. Labyrinth defects were particularly evident in placentas connected to effectively HIF-1α heterozygous null embryos. MATcKO had no effect on basal ODD-Luciferase activity in fetal organs (heart, liver, brain) at any stage, but at E13.5-15.5 resulted in enhanced induction of the ODD-Luciferase hypoxia reporter when the dam's inspired O₂ was reduced to 8% for 4 hours. MATcKO also slowed the growth after E13.5 of fetuses that were effectively heterozygous for Hif-1α, with most being non-viable at E15.5. The hearts of these E15.5 fetuses were abnormal with reduction in size, thickened epicardium and mesenchymal septum. We conclude that maternal HIF-1α is required for placentation including recruitment of uNK and trophoblast cells into the maternal decidua and other trophoblast cell behaviors. The placental defects render the fetus vulnerable to O₂ deprivation after mid-gestation.

Are hypertensive disorders in pregnancy associated with congenital malformations in offspring? Evidence from the WHO Multicountry cross sectional survey on maternal and newborn health

BACKGROUND

Annually, around 7.9 million children are born with birth defects and the contribution of congenital malformations to neonatal mortality is generally high. Congenital malformations in children born to mothers with hypertensive disorders during pregnancy has marginally been explored.

METHODS

Country incidence of congenital malformations was estimated using data on the 310 401 livebirths of the WHO Multicountry Survey which reported information from 359 facilities across 29 countries. A random-effect logistic regression model was utilized to explore the associations between six broad categories of congenital malformations and the four maternal hypertensive disorders "Chronic Hypertension", "Preeclampsia" and "Eclampsia" and "Chronic hypertension with superimposed preeclampsia".

RESULTS

The occupied territories of Palestine presented the highest rates in all groups of malformation except for the "Lip/Cleft/Palate" category. Newborns of women with chronic maternal hypertension were associated with a 3.7 (95 % CI 1.3-10.7), 3.9 (95 % CI 1.7-9.0) and 4.2 (95 % CI 1.5-11.6) times increase in odds of renal, limb and lip/cleft/palate malformations respectively. Chronic hypertension with superimposed preeclampsia was associated with a 4.3 (95 % CI 1.3-14.4), 8.7 (95 % CI 2.5-30.2), 7.1 (95 % CI 2.1-23.5) and 8.2 (95 % CI 2.0-34.3) times increase in odds of neural tube/central nervous system, renal, limb and Lip/Cleft/Palate malformations.

CONCLUSIONS

This study shows that chronic hypertension in the maternal period exposes newborns to a significant risk of developing renal, limb and lip/cleft/palate congenital malformations, and the risk is further exacerbate by superimposing eclampsia. Additional research is needed to identify shared pathways of maternal hypertensive disorders and congenital malformations.

Possible Common Aetiology behind Maternal Preeclampsia and Congenital Heart Defects in the Child: a Cardiovascular Diseases in Norway Project Study

BACKGROUND

The aetiology of congenital heart defects (CHD) is mostly unknown, but maternal factors may modify the infant risk of CHD. We investigated the association between maternal preeclampsia and offspring risk of severe CHD in a nation-wide cohort study.

METHODS

Information on all births registered in the Medical Birth Registry of Norway, 1994-2009, was completed with information on CHD diagnoses from national health registries and the Cardiovascular Diseases in Norway Project (CVDNOR).

RESULTS

Among 914 703 singleton births without chromosomal abnormalities, 32 864 (3.6%) were born after a pregnancy with preeclampsia. The preeclampsia was diagnosed before the 34th week of pregnancy (early-onset preeclampsia) in 2618 (8.0% of preeclamptic pregnancies). CHDs were diagnosed in 10 691 infants; of these, 2473 had severe CHD. The risk of severe CHD was compared between births with and without maternal preeclampsia and estimated with binomial log-linear regression. When adjusting for year of birth, maternal age, parity, and pregestational diabetes, the risk ratio (RR) for severe CHD in offspring of mothers with any preeclampsia was 1.3 [95% confidence interval (CI) 1.1, 1.5], and in pregnancies with early-onset preeclampsia, the RR was 2.8 (95% CI 1.8, 4.4). The association between early-onset preeclampsia and specific types of severe CHD was stronger for atrioventricular septal defects (AVSD), with adjusted RR 13.5 (95% CI 6.8, 26.8).

CONCLUSIONS

Early-onset preeclampsia was strongly associated with infant risk of severe CHD, specifically; the risk of AVSD was 15-fold higher if the mother was diagnosed with early-onset preeclampsia, suggesting common aetiological factors for early-onset preeclampsia and erroneous fetal heart development.

Changes in vitelline and utero-placental hemodynamics: implications for cardiovascular development

Analyses of cardiovascular development have shown an important interplay between heart function, blood flow, and morphogenesis of heart structure during the formation of a four-chambered heart. It is known that changes in vitelline and placental blood flow seemingly contribute substantially to early cardiac hemodynamics. This suggests that in order to understand mammalian cardiac structure-hemodynamic functional relationships, blood flow from the extra-embryonic circulation needs to be taken into account and its possible impact on cardiogenesis defined. Previously published Doppler ultrasound analyses and data of utero-placental blood flow from human studies and those using the mouse model are compared to changes observed with environmental exposures that lead to cardiovascular anomalies. Use of current concepts and models related to mechanotransduction of blood flow and fluid forces may help in the future to better define the characteristics of normal and abnormal utero-placental blood flow and the changes in the biophysical parameters that may contribute to congenital heart defects. Evidence from multiple studies is discussed to provide a framework for future modeling of the impact of experimental changes in blood flow on the mouse heart during normal and abnormal cardiogenesis.