Author + information
- Received September 6, 2018
- Revision received December 19, 2018
- Accepted January 6, 2019
- Published online April 29, 2019.
- Lauren E. Schlichting, PhDa,b,c,∗ (, )
- Tabassum Z. Insaf, PhDb,c,
- Ali N. Zaidi, MDd,
- George K. Lui, MDe and
- Alissa R. Van Zutphen, PhDb,c
- aHassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island
- bBureau of Environmental and Occupational Epidemiology, New York State Department of Health, Albany, New York
- cUniversity at Albany School of Public Health, Rensselaer, New York
- dMontefiore Medical Center, Children’s Hospital at Montefiore/Albert Einstein College of Medicine, New York, New York
- eStanford University School of Medicine, Stanford, California
- ↵∗Address for correspondence:
Dr. Lauren E. Schlichting, Hassenfeld Child Health Innovation Institute, 121 South Main Street, Providence, Rhode Island 02912.
Background Pregnant women with congenital heart defects (CHDs) may be at increased risk for adverse events during delivery.
Objectives This study sought to compare comorbidities and adverse cardiovascular, obstetric, and fetal events during delivery between pregnant women with and without CHDs in the United States.
Methods Comorbidities and adverse delivery events in women with and without CHDs were compared in 22,881,691 deliveries identified in the 2008 to 2013 National Inpatient Sample using multivariable logistic regression. Among those with CHDs, associations by CHD severity and presence of pulmonary hypertension (PH) were examined.
Results There were 17,729 deliveries to women with CHDs (77.5 of 100,000 deliveries). These women had longer lengths of stay and higher total charges than women without CHDs. They had greater odds of comorbidities, including PH (adjusted odds ratio [aOR]: 193.8; 95% confidence interval [CI]: 157.7 to 238.0), congestive heart failure (aOR: 49.1; 95% CI: 37.4 to 64.3), and coronary artery disease (aOR: 31.7; 95% CI: 21.4 to 47.0). Greater odds of adverse events were observed, including heart failure (aOR: 22.6; 95% CI: 20.5 to 37.3), arrhythmias (aOR: 12.4; 95% CI: 11.0 to 14.0), thromboembolic events (aOR: 2.4; 95% CI: 2.0 to 2.9), pre-eclampsia (aOR: 1.5; 95% CI: 1.3 to 1.7), and placenta previa (aOR: 1.5; 95% CI: 1.2 to 1.8). Cesarean section, induction, and operative vaginal delivery were more common, whereas fetal distress was less common. Among adverse events in women with CHDs, PH was associated with heart failure, hypertension in pregnancy, pre-eclampsia, and pre-term delivery; there were no differences in most adverse events by CHD severity.
Conclusions Pregnant women with CHDs were more likely to have comorbidities and experience adverse events during delivery. These women require additional monitoring and care.
Advancements in early diagnostic capabilities, improvements in surgical success rates, and wider availability of follow-up care have improved survival of individuals born with congenital heart defects (CHDs). It is estimated that adults compose approximately 66% of the CHD population, and approximately 1.5 million adults live with CHDs in the United States (1,2). Approximations using Canadian data suggest that there are between 556,000 and 640,000 women with CHD 18 years of age and older in the United States and that the adult population with CHDs is increasing at a rate of approximately 5% per year, leading to substantial growth of this cohort (2,3).
The number of deliveries to women with CHDs increased by 34.9% over a 10-year period from 1998 to 2007, a greater rise than the 21.3% increase observed in the general population (4). This is likely due to a combination of more infants with CHDs surviving to childbearing age and improved care for pregnant women with CHDs. However, the risk of adverse pregnancy outcomes is much higher in women with CHDs due to the strain pregnancy places on the cardiovascular system, including increased blood volume, heart rate, and cardiac output, and these women are at a higher risk for complications. Due to the increased burden placed on the mother’s cardiovascular system, women with CHD are more likely to experience heart failure, stroke, arrhythmias, and myocardial infarction (4–9). Furthermore, pregnant women with CHDs experience a higher frequency of adverse obstetric events, such as pre-term labor, maternal death, operative vaginal delivery, and cesarean delivery (5–7,9–12). Children born to women with CHDs are also placed at a higher risk for a number of adverse outcomes, including small for gestational age, premature birth, and reoccurrence of CHDs or other congenital anomalies (10,12). However, few prior analyses have used large, nationally representative databases of U.S. CHD patients to examine the association between CHDs and the occurrence of cardiac, obstetric, and fetal outcomes in pregnant women, because much of the previous research has involved smaller studies at clinics or hospital facilities. It is important to investigate whether women with more severe or complex defects are at an increased risk for certain delivery complications and require additional medical care.
Pregnant women with CHDs face an even greater risk for adverse events during pregnancy and delivery when a comorbidity is present (4). Women with CHDs have greater rates of comorbidities that may complicate delivery, including cardiomyopathy, valvular heart disease, pulmonary hypertension (PH), systemic hypertension, cardiac conduction disorder, anemia, and nongestational diabetes, with the prevalence of these comorbidities continuing to rise in the CHD population (5,7,13). In particular, studies have noted an increased risk for adverse events during pregnancy for women with PH, one of the most common comorbidities among CHDs patients (4,9). Previous studies have focused on cardiovascular comorbidities in pregnant women with CHDs; however, insight into noncardiovascular comorbidities and how comorbidities differ on the basis of disease severity or the presence of PH would aid in the care of these women throughout pregnancy. The goal of the present study was to examine the presence of comorbidities and the occurrence of obstetric, fetal, and cardiovascular complications during delivery among women with and without CHDs hospitalized for delivery using data from the National (Nationwide) Inpatient Sample (NIS), a nationally representative sample of discharges from hospitals in the United States. In addition, maternal comorbidities and adverse delivery events were assessed by CHD severity level.
The NIS for the years 2008 to 2013 was used to investigate delivery outcomes in pregnant women 15 to 44 years of age with CHDs. The NIS is a stratified, cross-sectional database that includes discharge data for approximately 20% of all discharges in the United States, making it the largest all-payer inpatient care database in the country. The NIS is compiled yearly by the Healthcare Cost and Utilization Project (HCUP) of the Agency for Healthcare Research and Quality and includes all patients in community hospitals, including patients with Medicare, Medicaid, or private insurance coverage, as well as uninsured patients. In 2012, the NIS was redesigned and the sampling mechanism changed (14). Before 2012, a sample of hospitals was selected, and the database was composed of all discharges from the selected hospitals. Starting in 2012, the NIS sampled discharges from all community hospitals participating in HCUP. Stratification of hospitals on the basis of census region (2008 to 2011) or division (2012 to 2013), urban/rural location, ownership, bed size, and teaching status provide the representativeness of the database. Weights are provided by HCUP, which allows researchers to use the database to estimate approximately 35 million hospitalizations across the United States annually.
Delivery hospitalizations from the NIS databases were collected for analysis using an enhanced delivery identification method (15). Medicare diagnosis-related group delivery codes were used to identify vaginal (767, 768, 774, and 775) and cesarean (765 and 766) delivery hospitalizations. Delivery hospitalizations were also identified using International Classification of Diseases-9th Revision-Clinical Modification (ICD-9-CM) codes for outcome of delivery (V27), normal delivery (650), and disease codes for pregnancy/labor complications (640.0 to 676.9, where the fifth digit is 1 or 2). Selected delivery-related procedure codes 72.x, 73.x, and 74.x (excluding 74.91) were also used to identify delivery records.
To identify pregnant women with CHDs, ICD-9-CM codes 745.x to 747.x were used, on the basis of the CHD eligibility definition developed by the Centers for Disease Control and Prevention and grantees from the “Surveillance of Congenital Heart Defects Focusing on Adolescents and Adults” project (CDC-RFA-DD12-1207) (16). Delivery hospitalizations possessing only ICD-9-CM codes 746.86 (congenital heart block), 747.32 (pulmonary arteriovenous malformation/aneurysm), 747.5 (absence or hypoplasia of umbilical artery), 747.6x (other anomalies of peripheral vascular system), or 747.8x (other specified anomalies of circulatory system) were excluded from the CHD case cohort, because these malformations are classified as part of the greater circulatory or peripheral vascular system, rather than defects of the heart.
A 5-category CHD ICD-9-CM code classification scheme developed for the CDC-RFA-DD12-1207 project based on the classification system by Marelli et al. (16) was used to classify women into a single CHD severity group (17). Five mutually exclusive categories were created: severe, shunt + valve, shunt only, valve only, and other (Online Table 1). Women with CHDs were further classified into 3 groups for analysis: severe CHD, mild-to-moderate CHD, and isolated atrial septal defect (ASD). The severe CHD group is composed of individuals with an ICD-9-CM code in the severe category of the classification system. The mild-to-moderate CHD group is composed of individuals within the shunt, valve, shunt + valve, and other categories, excluding those with an isolated 745.5 ICD-9-CM code who composed the isolated ASD group. Because isolated ASDs are a milder form of CHD and the code used often includes patent foramen ovale (PFO), they were placed in a separate group.
To examine the prevalence of various comorbid conditions among pregnant women with CHDs, data were extracted on other conditions present. Comorbidities were categorized using the Clinical Classifications Software (CCS) tool developed by the Agency for Healthcare Research and Quality (18). CCS is a grouping scheme that collapses thousands of ICD-9-CM codes into over 200 diagnosis categories. The CCS categories were further collapsed into 12 broader comorbidity groups for the CDC-RFA-DD12-1207 project (16). Comorbidities examined included systemic hypertension, PH, congestive heart failure, coronary artery disease, conduction and rhythm disorders, other cardiovascular conditions, birth defects (non-CHD), diabetes mellitus, hyperlipidemia, mental health, neurological and central nervous system, and respiratory and pulmonary conditions (Online Table 2).
Cardiovascular complications included myocardial infarction, arrhythmias, heart failure, and thromboembolic events (e.g., stroke, pulmonary embolism). Obstetric complications examined were hypertension during pregnancy, pre-eclampsia, pre-term delivery, hemorrhage, placental abruption, placenta previa, and prolonged pregnancy. Fetal complications of interest included fetal malformation, fetal distress, fetal death or stillbirth, and fetal growth restriction. Delivery events examined included cesarean section, induction, artificial rupture of the membranes, and operative vaginal delivery (Online Table 3).
Bivariate analyses were conducted to assess differences in demographic variables between women with and without CHDs presenting to a hospital for delivery. Standard deviations were reported for continuous variables where the mean was calculated. Chi-square tests were used for categorical variables. The Student’s t-test was used for normally distributed, continuous variables, whereas the Wilcoxon signed rank test was used for non-normally distributed, continuous variables. Demographic statistics of women with CHDs admitted for delivery, by CHD severity, were also computed.
Crude and adjusted odds ratios (aORs) and their 95% confidence intervals (CIs) were calculated for each of the comorbid conditions as well as the cardiovascular, obstetric, fetal, and delivery events of interest using logistic regression. These analyses were conducted comparing delivery hospitalizations in women with CHDs to women without CHDs, as well as comparing women with severe or mild-to-moderate CHD to women with an isolated ASD. Analyses were also conducted comparing comorbid conditions and complications among pregnant women with CHDs who did and did not possess a code for PH (ICD 9-CM 416.x). Covariates considered for adjustment based on the published reports and directed acyclic graphs included age, race/ethnicity, primary insurance status, method of delivery, and teaching hospital status. To create the final, parsimonious model, purposeful selection procedures were used (19). Each covariate was removed from the model, and if the resulting change in estimate for the lead term was >10%, the variable was adjusted for in the final model. To determine whether effect modification was present, an interaction term was added to the model between the covariate and the lead term. A likelihood ratio test was conducted with the full and reduced models, and if the likelihood ratio test showed significance with a p value <0.05, then the interaction term remained in the final model. Effect modifiers considered included race/ethnicity and primary insurance.
HCUP-provided weights and SAS survey procedures were used with all analyses to account for the complex sampling design and clustering by hospital in the analysis (14). The HCUP data use agreement prohibits the publication of information based on cell sizes ≤10; these instances are indicated in the reported tables. For all analyses, statistical significance was assigned based on a p value of <0.05. Model fit was evaluated using deviance and Pearson statistics tests. All statistical analyses were conducted using SAS software version 9.3 (SAS Institute, Cary, North Carolina).
There were approximately 22,881,691 deliveries in the United States between 2008 and 2013. Among the delivery hospitalizations, 17,729 were to women with CHDs (77.5 of 100,000 deliveries). Mild-to-moderate CHDs were present in 70% (n = 12,366) of CHD patients, whereas 25% of patients possessed an isolated ASD (n = 4,375). Only 5% of deliveries to women with CHDs were to patients with severe CHDs (n = 988).
Patients with CHDs were more likely to attend a teaching hospital for delivery (64.3% vs. 47.5%; p < 0.001), to have a longer length of stay (2.3 [interquartile range (IQR): 1.5 to 3.2] days vs. 1.8 [IQR: 1.3 to 2.6] days; p < 0.001), and to have higher total charges ($13,615 [IQR: $8,899 to $21,855] vs. $10,985 [IQR: $7,398 to $16,657]; p < 0.001) than patients without CHDs (Table 1).
The mean age at time of delivery was significantly different between the 3 severity groups, with women possessing severe defects delivering at a younger age than those with other forms of CHDs (Table 2). Women with severe CHDs were more likely to attend a teaching hospital (76.6%) than women with mild-to-moderate CHDs (63.5%) or an isolated ASD (63.9%) (p < 0.001). Women with severe CHDs also had a longer hospital stay (2.6 [IQR: 1.7 to 3.7] days) than women with mild-to-moderate CHDs (2.2 [IQR: 1.5 to 3.1] days) or an isolated ASD (2.3 [IQR: 1.5 to 3.2] days; p < 0.007) and higher total charges (p < 0.03).
The aORs for the following comorbidity categories were significantly greater for pregnant women with CHDs than pregnant women without CHDs: systemic hypertension, PH, congestive heart failure, coronary artery disease, conduction and rhythm disorders, other cardiovascular conditions, birth defects, hyperlipidemia, mental health conditions, neurological and central nervous system conditions, and respiratory/pulmonary conditions (Table 3).
The percentage of women with severe CHDs who also had congestive heart failure, conduction and rhythm disorders, other cardiovascular conditions, or birth defects was greater than the percentage of women with mild-to-moderate CHDs or isolated ASD with these comorbidities (Figure 1).
Adverse events in pregnant women with and without CHDs
The aORs for cardiac events, including heart failure, arrhythmia, and thromboembolic events were significantly greater among pregnant women with CHDs than pregnant women without (Table 4). Pregnant women with CHDs had significantly greater odds of all but 1 obstetric event, including hypertension in pregnancy, pre-eclampsia, placenta previa, hemorrhage, placental abruption, and pre-term delivery (Table 4). Women with CHDs featured significantly lower odds of prolonged pregnancy than women without CHDs (aOR: 0.6; 95% CI: 0.5 to 0.7), as well as lower odds of fetal distress (aOR: 0.8; 95% CI: 0.7 to 0.9). Odds of other fetal events, such as fetal malformation and fetal growth restriction were significantly higher in women with CHDs compared with women without. The aORs for various methods of delivery assistance, including cesarean section, induction, and operative vaginal delivery, were significantly greater for women with CHDs than women without CHDs.
Adverse events in pregnant women by disease severity
Pregnant women with severe or mild-to-moderate CHDs had a significantly lower aOR for thromboembolic events than pregnant women with isolated ASDs (Table 5). There was no difference in the odds for other cardiovascular events, adverse obstetric events, or fetal events between the 2 groups. Pregnant women with severe or mild-to-moderate CHDs had greater odds for operative vaginal delivery and cesarean section, whereas pregnant women with an isolated ASD had greater odds for artificial rupture of the membranes.
Adverse events in pregnant women by pulmonary hypertension status
Among pregnant women with CHDs, women with PH had significantly greater odds of heart failure than women without PH (Table 6). There was no difference in the odds for other cardiovascular events or fetal events between the 2 groups. Women with PH also had greater odds of obstetric events, including hypertension in pregnancy, pre-eclampsia, and pre-term delivery, as well as greater odds for cesarean section than women without PH.
Women with CHDs are at an increased risk for numerous cardiovascular, obstetric, and fetal events at the time of delivery. The odds of an adverse maternal cardiac event during delivery were 2.4 to 27.6 times higher for women with CHDs compared with women without. Among the cardiac events examined, the odds of heart failure during delivery were the highest, consistent with the findings of Opotowsky et al. (4) and Thompson et al. (5) using earlier NIS data from 1998 to 2007 and 2000 to 2010, respectively. The risk of arrhythmias and thromboembolic events during childbirth was also significantly greater in women with CHDs, in agreement with findings in previous studies (4,5,9). However, the associations were markedly different among women with different defect types because the odds of arrhythmias did not appear to differ by CHD severity, whereas women with isolated ASD were more likely to experience a thromboembolic event (Central Illustration). This may be due in part to the smaller sample sizes available in the subanalysis by severity and warrants examination in future studies.
An increased risk of hypertension in pregnancy was found in women with CHDs compared with women without CHDs. However, there was no significant difference in risk for hypertension in pregnancy for women with severe or mild-to-moderate forms of CHDs, compared with women with an isolated ASD. Previous findings by Krieger et al. (6) reported an increased risk of both existing and gestational hypertension in women with coarctation of the aorta compared with women without; however, our results may differ due to our analysis of multiple, varied CHD types, not just coarctation of the aorta.
PH did not greatly increase the risk for most complications among pregnant women with CHDs. Similar to previous findings by Opotowsky et al. (4), the presence of PH had a strong effect on the relationship between CHDs and heart failure during childbirth, but little effect on arrhythmia. A few obstetric events, including pre-eclampsia, pre-term delivery, and hypertension in pregnancy, were more likely among pregnant women with CHDs who possessed PH; however, there were no significant increases in risk for fetal events. Although the present data do not suggest increased complications among women with PH, the risk may be underestimated as pre-existing conditions, such as PH, are not always coded in the patient's discharge record, the severity is often not reflected by the code used, and it is unknown how the diagnosis is obtained or validated.
The risk for pre-eclampsia and placenta previa has been examined by few studies of pregnant women with CHDs, and as a result, the present findings provide preliminary evidence of an increased risk for 2 serious adverse events affecting both the mother and the newborn. In a study by Ruys et al. (20), pregnant women with structural heart disease, including those with CHDs, showed an increased risk for pre-eclampsia with heart failure compared with those without structural heart disease. Additionally, Hayward et al. (7) found women with noncomplex CHDs had significantly increased odds of pre-eclampsia or eclampsia, whereas the association for complex CHDs was not found to be significant. However, further research with other data sources may seek to confirm the increased risk for pre-eclampsia and placenta previa.
Women with CHDs also showed significantly increased odds of other adverse obstetric events, including pre-term delivery, hemorrhage, and placental abruption. Interestingly, women with CHDs featured significantly lower odds of prolonged pregnancy, which is likely related to a low threshold for operative delivery or Cesarean section in women with CHDs. Consistent with previous studies, women with CHDs were 1.6 times more likely to undergo a Cesarean section than women without CHDs (5,10–12). Furthermore, women with CHDs featured significantly greater odds of an operative vaginal delivery than women without CHDs, as also shown by Thompson et al. (5). Due to the decreased functional capacity of women with CHDs, physicians may more readily recommend delivery interventions to laboring women with CHDs to improve the outcome of delivery. However, the increase in the cesarean section rate for all pregnant women has raised concerns about the short- and long-term impact of these types of delivery procedures on both the woman and the child, and therefore, researchers may seek to investigate the long-term effects for women with CHDs.
Infants born to mothers with CHDs were more likely to possess birth defects or exhibit growth restriction at birth, but less likely to experience fetal distress. These infants may experience growth restriction due to the medications taken by women with CHDs or the comorbidities of the mother, such as heart failure or arrhythmias. Although it is unclear as to the factors contributing to the decreased risk for distress, because previous studies have not examined this type of event, it is possible that the increased use of assisted delivery methods resulted in deliveries occurring before a child became distressed during labor.
Pregnant women with CHDs exhibited increased health care utilization, as evidenced by their significantly longer hospital stays for delivery and higher charges than women without CHDs. Prior analyses by Briston et al. (21) showed an increase in the number of discharges and expenditures for adults with CHDs, in agreement with the present findings. Moreover, we found that pregnant women with more severe forms of CHDs had significantly longer lengths of stay and higher charges than pregnant women with an isolated ASD, as previously observed in the general adult CHD population (13,21,22). Due to the complex health care needs of individuals with CHDs, higher utilization of services is required to preserve the health of both mother and child.
The results suggest that the risk for most adverse events during delivery are not significantly different for women with different severities of CHDs, despite higher charges and longer hospitals stays indicating a more complicated delivery. Although the sample size was larger than most studies of women with CHDs, the complications are still rare events, and therefore, differences in risk may not have been fully ascertained. Nevertheless, a few noteworthy observations were obtained from the analysis, such as women with severe and mild-to-moderate forms of CHDs exhibited a large number of stillbirths and had a significantly lower risk of thromboembolic events, such as stroke or pulmonary embolism, than women with isolated ASD. However, the higher frequency of thromboembolic events in women with isolated ASD may be the result of misclassification in our isolated ASD group. The ASD/PFO code (ICD-9-CM 745.5) may be recorded in pregnant women without CHDs suspected of transient ischemic attack or stroke who receive an echocardiogram to rule out ASD/PFO. These women would be misclassified into the isolated ASD group, and the number of thromboembolic events would be inflated.
The current findings add to a growing body of published reports on the comorbidities present in individuals with CHDs and provide insight into the overall health status of the individual before delivery and how it may influence the occurrence of delivery complications. Pregnant women with CHDs featured significantly greater odds of 10 of the comorbidities examined, with the greatest increase in odds observed for cardiovascular comorbidity groups, in agreement with previous studies (5). Only the odds of diabetes mellitus was not significantly different between the 2 groups, contrasting with the prior findings from Thompson et al. (5), who reported significantly greater odds for nongestational diabetes in pregnant women with CHDs. Further analysis of comorbidities by CHD severity revealed differences in conditions present on the basis of CHD category; however, smaller sample sizes prevented adequately powered calculations of risk by severity level.
Study strengths and limitations
Most studies of maternal CHDs in pregnancy have included small sample sizes due to reliance on data from a single medical facility or a small group of medical centers due to the absence of a nationwide adult CHDs database in the United States. Analyses using the NIS provide a much larger, population-based sample of patients, an important benefit when examining a rare condition, such as CHDs. The examination of multiple years of NIS data allows for a larger sample of individuals with CHDs to be collected and enables exploratory analyses by CHD severity. A few previous studies (4,5,9,11) have examined maternal CHDs in pregnancy using the NIS; however, the present analysis includes the most recent data, considers additional complications and comorbidities, and evaluates the women in regard to the severity of their defect. Furthermore, many of the larger previously published studies have utilized data from Europe and Canada, which are not entirely generalizable to the U.S. population. The United States features a more racially diverse population and a unique health insurance system that results in different levels of prenatal care for pregnant women than seen in other nations.
The information on the presence of CHDs, comorbidities, and complications in a patient is reported by the health care provider, rather than by the patient as in some other studies of pregnant women with CHDs, lending greater validity to the NIS data. However, because the data contained within the NIS were not collected for research purposes, but rather are used for medical coding and billing, a limitation of the study is that information may be incomplete or incorrect. Comorbidities are likely underreported because they are often not relevant to administrative processes, and the presence of comorbidities on the patient’s record may even negatively impact their insurance eligibility. Likewise, there is also the potential for cardiovascular complications to not be coded or to be coded as an event during the delivery record, when in fact it is a notation of the history of the patient. Conversely, these comorbid conditions and complications may be miscoded or left out of the records of non-CHD patients. These 2 types of errors would result in an overestimation of the effect of CHDs if it were to occur more frequently in those with CHDs than those without CHDs.
Additionally, an individual may not have a CHD code in their record, when in reality they possess a CHD, especially among patients with less severe forms or repaired CHDs. A patient could also potentially possess an incorrect code in their discharge record classifying them as a different subtype of CHD. This would be problematic for severity analyses if the incorrect code places them into a different severity category. Nevertheless, there is no indication that one group is more likely to experience missing codes or incorrect coding than the other.
Because the NIS is a database of discharge-level data, not patient-level data, it is not possible to examine the history of a woman to determine whether she possesses a repaired or unrepaired defect. Such information would further inform our analyses but is unavailable in the NIS. Future analyses should examine the effect of defect repair, in addition to severity of the defect, on pregnancy outcomes. Additionally, the present analysis was only focused on complications at the delivery hospitalization. Because complications occur throughout pregnancy, not just at delivery, and have an impact on the likelihood of complications during delivery, it is important for future analyses to examine the entire pregnancy period. Furthermore, because there are no linkages available between the records of the mother and the infant, fetal complications were only ascertained from those listed on the maternal record. As a result, the data on neonatal complications may be incomplete.
Women with CHDs are more likely to possess comorbidities and experience adverse cardiovascular, obstetric, and fetal events at delivery than women without CHDs. As a result, women with CHDs, especially severe forms, have complex health care needs and increased health care utilization, as evidenced by their longer hospital stays and higher delivery charges. This study contributes a more detailed analysis of CHD subgroups and the impact of defect severity and pre-existing PH on pregnancy events. Further studies are necessary to determine whether there is a difference in outcomes for women with severe and mild forms of CHDs and if so, the associated increase in risk, in order to provide more comprehensive and tailored treatment to pregnant women with CHDs.
COMPETENCY IN MEDICAL KNOWLEDGE: Women with congenital heart disease (CHD) are more likely to experience adverse cardiovascular, obstetrical, and fetal events at delivery and longer hospital stays than those without CHD. Pulmonary hypertension associated with CHD is a significant predictor of maternal heart failure and caesarean delivery.
TRANSLATIONAL OUTLOOK: More research is needed to determine whether management in centers with special expertise in CHD improves the outcomes of pregnancy.
This work was funded by the Centers for Disease Control and Prevention grants CDC-RFA-DD12-1202, CDC-RFA-CK12-1202, and CDC-RFA-DD15-1506. The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Ami Bhatt, MD, served as the Guest Associate Editor for this paper.
Listen to this manuscript's audio summary by Editor-in-Chief Dr. Valentin Fuster on JACC.org.
- Abbreviations and Acronyms
- adjusted odds ratio
- atrial septal defect
- clinical classification system
- congenital heart defect
- confidence interval
- Healthcare Cost and Utilization Project
- International Classification of Diseases-9th Revision-Clinical Modification
- National Inpatient Sample
- patent foramen ovale
- pulmonary hypertension
- Received September 6, 2018.
- Revision received December 19, 2018.
- Accepted January 6, 2019.
- 2019 The Authors
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- Webb G.D.,
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- Landzberg M.J.
- Hayward R.M.,
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- Briston D.A.,
- Bradley E.A.,
- Sabanayagam A.,
- Zaidi A.N.