Pregnancy in women with congenital heart disease: General principlesAuthorsCarol A Waksmonski, MDMichael R Foley, MDSection EditorsCharles J Lockwood, MD, MHCMHeidi M Connolly, MDDeputy EditorSusan B Yeon, MD, JD, FACCDisclosures: Carol A Waksmonski, MD Nothing to disclose. Michael R Foley, MD Nothing to disclose. Charles J Lockwood, MD, MHCM Consultant/Advisory Boards: Celula [Aneuploidy screening (Prenatal and cancer DNA screening tests in development)]. Equity Ownership/Stock Options: Celula [Aneuploidy screening (Prenatal and cancer DNA screening tests in development)]. Heidi M Connolly, MD Nothing to disclose. Susan B Yeon, MD, JD, FACC Employee of UpToDate, Inc. Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence. Conflict of interest policyAll topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jan 2015. | This topic last updated: Jan 08, 2015. INTRODUCTIONProgress in surgical treatment has resulted in larger numbers of women with congenital heart disease surviving to proceeding with pregnancy [1]. The general principles of management of pregnancy and contraception in women who have unrepaired or repaired congenital malformations of the heart or great vessels will be reviewed here. Pregnancy in women with specific congenital cardiac anomalies, the management of valvular heart disease during pregnancy, and the management of heart failure and arrhythmias during pregnancy are discussed separately. (See "Pregnancy in women with congenital heart disease: Specific lesions" and "Pregnancy and valve disease" and "Management of heart failure during pregnancy" and "Supraventricular arrhythmias during pregnancy" and "Ventricular arrhythmias during pregnancy".)EPIDEMIOLOGYSuccessful cardiac surgery improves fertility and reduces the maternal and fetal risk of pregnancy in women with congenital heart disease [2,3]. Accordingly, women are now presenting for obstetric and cardiologic care after reparative cardiac surgery [1]. In a registry of the European Society of Cardiology, congenital heart disease was the most prevalent form of structural heart disease (66 percent) affecting pregnancy outcomes worldwide [4]. Congenital heart disease remains an important cause of maternal mortality and morbidity during pregnancy. The magnitude of risk is illustrated by the following observations:In a report of maternal deaths from 2000 to 2002 in the United Kingdom, cardiac disease was the second most common cause, with congenital heart disease accounting for 20 percent of cardiac deaths [5].Maternal morbidity was evaluated in a review of mostly retrospective reports published from 1985 to 2006 that described the outcomes of 2491 pregnancies in women with structural congenital heart disease [6]. The following findings were noted:Cardiac complications were documented in 11 percent of completed pregnancies, with heart failure (5 percent) and arrhythmias (4.5 percent) the most common.Cardiovascular events such as myocardial infarction, stroke, and cardiovascular mortality were reported primarily in Eisenmenger patients and in those with palliated or unrepaired cyanotic heart disease. (See "Medical management of Eisenmenger syndrome".)Hypertensive disorders related to pregnancy were reported in 9 percent of pregnancies, which is comparable to the rate expected in the general population [7], but were more frequent in patients with transposition of the great arteries, aortic coarctation, pulmonic valve stenosis, or aortic stenosis.Gravidas with congenital heart disease may be at higher risk during an individual pregnancy, but if they survive, the risk of pregnancy is generally not cumulative. Thus, successive pregnancies generally entail the same but not greater risk.CARDIOVASCULAR CHALLENGES DURING PREGNANCYHemodynamic changesNormal alterations in circulatory and respiratory physiology during pregnancy can have deleterious effects on the mother with congenital heart disease and on her developing fetus. There are two major hemodynamic changes: fall in systemic blood pressure and increase in cardiac output. (See "Maternal cardiovascular and hemodynamic adaptations to pregnancy".)Systemic blood pressure typically falls early in gestation and is usually 10 mmHg below baseline in the second trimester, declining to a mean of 105/60 mmHg. This response reflects a reduction in systemic vascular resistance that serves to increase flow across right-to-left shunts.A 30 to 50 percent increase in intravascular volume and cardiac output occurs in normal pregnancy by the early to mid third trimester. In patients whose cardiac output is limited by myocardial dysfunction or valvular lesions (eg, mitral stenosis), volume overload is poorly tolerated and may result in heart failure. Marked fluctuations in cardiac output occur during normal labor and delivery. Cardiac output increases progressively from the first stage of labor, sometimes reaching an additional 50 percent by the late second stage. The potential for dramatic volume shifts is heightened at the time of delivery in response to the physiologic transfusion, which occurs with release of vena caval obstruction and blood from the now contracted uterus; postpartum hemorrhage may exacerbate these volume shifts, which are tolerated poorly by women whose cardiac output is highly dependent upon adequate preload.Risk of thromboembolismIn addition to the normal hemodynamic changes of pregnancy, cardiac reserve can be impaired by thromboembolism. Pregnancy is associated with an increased thromboembolic risk due to lower extremity venous stasis resulting from inferior vena caval compression by the gravid uterus, and to a hypercoagulable state due to an increase in vitamin K dependent clotting factors and a reduction in free protein S. (See "Deep vein thrombosis and pulmonary embolism in pregnancy: Prevention".)A review cited above found a 2 percent incidence of thromboembolic events in 688 completed pregnancies in women with congenital heart disease [6] compared to an expected rate of 0.05 to 0.10 percent during uncomplicated completed pregnancies [8]. Potential risk factors for thromboembolism were not evaluated.The issue of hypercoagulability is of particular relevance in women at risk for thrombosis related to prosthetic heart valves, atrial fibrillation, or previous thromboembolic events. (See 'Prenatal care' below.) MATERNAL RISK STRATIFICATIONMaternal cardiovascular risk assessmentOverviewWe agree with the 2011 European Society of Cardiology task force recommendation to use the modified World Health Organization (WHO) risk classification for maternal risk assessment [9]. The modified WHO classification provided the best risk assessment in the prospective study by the ZAHARA investigators described below [10]. The modified WHO risk classification includes contraindications for pregnancy not included in the two frequently used indices for material cardiovascular risk with congenital heart disease: the CARPREG (Cardiac Disease in Pregnancy) and the ZAHARA (Zwangerschap bij vrouwen met een Aangeboren HARtAfwijking-II, translated as Pregnancy in women with congenital heart disease II) scoring systems. A prospective study examined outcomes in 213 pregnancies in 203 women with congenital heart disease and compared the performance of the modified WHO classification, CARPREG and ZAHARA risk scores, as well as total numbers of cardiovascular predictors and offspring risk predictors:Maternal cardiovascular events occurred during 22 pregnancies (10 percent)The highest area under the curve (AUC) for maternal cardiovascular risk was achieved by the modified WHO class (AUC: 0.77). The AUC for the ZAHARA risk score was 0.71 and the CARPREG risk score was 0.57; the latter was not significantly different from random guess. Modified WHO classificationThe Working Group on Pregnancy and Contraception classified pregnancy risk in women with heart disease using modified World Health Organization (WHO) classification categories [11]. We agree with the classification adopted in the 2011 European Society of Cardiology guidelines for management of cardiovascular disease during pregnancy [12]: Class I conditions are associated with no detectable increased risk of maternal mortality and no/mild increase in morbidity. Conditions in this category include uncomplicated, small, or mild pulmonic stenosis, patent ductus arteriosus, or mitral valve prolapse; successfully repaired simple lesions (atrial or ventricular septal defect, patent ductus arteriosus, or anomalous pulmonary venous drainage); and isolated atrial or ventricular ectopic beats Class II conditions are associated with small increased risk of maternal mortality or moderate increase in morbidity. Conditions in risk class II include unrepaired atrial or ventricular septal defect, repaired tetralogy of Fallot, most arrhythmias. Conditions in risk class II to III (depending on the individual) include mild left ventricular impairment, hypertrophic cardiomyopathy, native or tissue valvular heart disease not considered WHO I or IV, repaired coarctation, Marfan syndrome without aortic dissection, and bicuspid aortic valve with ascending aorta diameter 50 mm, Marfan syndrome with aorta dilated >45 mm, severe systemic ventricular systolic dysfunction (left ventricular ejection fraction 25 mmHg at rest or >30 mmHg with exercise). Recommendations for follow-up for patients with conditions in each of these categories is discussed below. (See 'Prenatal care' below.)ZAHARA scoreThe ZAHARA score is based upon a retrospective observational cohort study of 1302 completed pregnancies in 714 women with exclusively congenital heart disease, including predominantly complicated lesions [13]. The ZAHARA risk score is derived from a weighted scoring system to predict adverse maternal cardiac events and includes the following factors:Mechanical heart valve (4.25 points)Severe left heart obstruction (mean pressure gradient >50 mmHg or aortic valve area 3.51, 70.0 percent risk, respectively. However, the ZAHARA score has not been validated in other studies. (See 'Overview' above.)CARPREG risk scoreThe CARPREG risk score is based upon a retrospective study that examined the risks and predictors of pregnancy-related cardiac complications in women with heart disease [14]. The findings were then applied by the Cardiac Disease in Pregnancy (CARPREG) investigators in a prospective study of 562 women with congenital or acquired cardiac disease or arrhythmias who had endured 617 pregnancies. Seventy-four percent of the pregnancies occurred in women with congenital heart disease [15].Four predictors of cardiac events were identified:Poor functional class (NYHA class III or IV) (table 1) or cyanosis Previous cardiovascular events including heart failure, a transient ischemic attack, stroke, or arrhythmiaLeft heart obstruction (mitral valve area of 128 pg/mL at 20 weeks gestation, the presence of a mechanical valve, and subpulmonary ventricular dysfunction before conception (odd ratios 10.6, 12.0, and 4.2, respectively).The negative predictive value of NT-proBNP levels 128 pg/mL was 18.3 percent.Addition of NT-proBNP level >128 pg/mL at 20 weeks gestation to the two preconception independent predictors significantly improved the area under the receiver operating curve (from 0.78 to 0.90).Less evidence is available on the utility of B-type natriuretic peptide (BNP) levels for risk stratification in pregnant women with congenital heart disease. Median plasma BNP levels during normal pregnancy are approximately twofold those in nonpregnant controls [25], while median BNP levels in a series of 66 pregnant women with congenital and acquired heart disease were over twofold those in 12 pregnant women without heart disease [26]. Elevated BNP (>100pg/mL) was found in all eight women who developed adverse cardiac events (defined as arrhythmia requiring treatment, stroke, cardiac arrest or cardiac death, pulmonary edema, decline in NYHA function class by at least two classes, or need for urgent invasive cardiac procedures during pregnancy or within six months after delivery). Elevated BNP level detection preceded the adverse event in four women. One-third of women with BNP >100pg/mL had an adverse cardiac event. FETAL RISKRisk assessmentThe functional class of the mother, maternal cyanosis, and other factors such as maternal medications expose the fetus to risks that threaten normal intrauterine growth and development. (See "Use of anticoagulants during pregnancy and postpartum" and "Supraventricular arrhythmias during pregnancy", section on 'Safety during pregnancy' and "Management of heart failure during pregnancy" and "Management of heart failure during pregnancy", section on 'Drugs'.)A fetal risk assessment score has not been established. A registry study including 1321 pregnant women with structural or ischemic heart disease (66 percent with congenital heart disease) found strong associations between modified World Health Organization (WHO) class and offspring outcome, especially preterm birth and birth weight [4]. A prospective study of 213 pregnancies in 203 women with congenital heart disease found that risk assessment using modified WHO classification, ZAHARA offspring risk score, CARPREG offspring risk score, and number of offspring predictors showed increases in class or risk score with increased offspring risk [10]. However none of these methods adequately predicted offspring events (area under the curve [AUC] 0.6 for all). Maternal functional classMaternal functional class (table 1) is a major determinant of fetal mortality, with risk ranging from not raised above baseline risk for gravidas who are asymptomatic to about 30 percent for gravidas with severe symptoms [1]. In pregnant women with the Eisenmenger syndrome, for example, only 15 to 25 percent of pregnancies progress to term. Spontaneous abortion is common, and there is appreciable perinatal mortality associated with fetal growth restriction and preterm delivery [18]. (See "Medical management of Eisenmenger syndrome".)Maternal cyanosisWomen with cyanotic congenital heart disease but no pulmonary hypertension can go through pregnancy with a relatively low maternal risk, although fetal risk is increased.Maternal cyanosis compromises fetal growth and increases prematurity and fetal loss [27,28]. Fetal outcomes were reported in a review of 96 pregnancies in women with cyanotic congenital heart disease [20]. The following findings were commented on:Only 43 percent of pregnancies resulted in a live birth, 37 percent of which were prematureThe rate of spontaneous abortion increased in parallel with maternal hypoxemiaThe mean birth weight of full-term infants was 2575 grams compared to a normal term birth weight of 3500 grams.Even when pre-gestational cyanosis is mild, the incidence of fetal loss is not insignificant because right-to-left shunts tend to increase during the course of pregnancy in response to the fall in systemic vascular resistance.Antepartum fetal monitoring should begin as soon as an increased risk of fetal demise is identified and delivery for perinatal benefit would be considered if test results are abnormal. This is generally between 26 and 32 weeks of gestation, with the specific time based on patient specific factors. (See "Nonstress test and contraction stress test", section on 'Antepartum fetal heart rate testing' and "Fetal growth restriction: Evaluation and management".) OutcomesOverall fetal outcomes in mothers with congenital heart disease have been assessed in a number of studies. The following observations illustrate the range of findings:In retrospective reports of 2491 pregnancies in women with structural congenital heart disease, miscarriage occurred in 15 percent, and 5 percent of women chose to terminate their pregnancies [6]. Fetal mortality was 1.7 percent and perinatal mortality was 2.3 percent (compared to less than 0.5 percent in the general population). The relatively high rate of premature births (16 percent) and the occurrence of congenital heart disease in the offspring are important variables. (See 'Inheritance' below.)The prospective Cardiac Disease in Pregnancy (CARPREG) study evaluated 562 women with congenital or acquired cardiac disease or arrhythmias who had 617 pregnancies; 74 percent of the pregnancies occurred in women with congenital heart disease [15]. Neonatal complications occurred in 122 pregnancies (20 percent). The major complications were premature birth in 105 pregnancies (17 percent), one-half of which were due to preterm labor, and small for gestational age in 22 pregnancies (4 percent). Less common complications included respiratory distress syndrome or intraventricular (cerebral) hemorrhage as complications of premature birth in 17 pregnancies (3 percent overall, but 16 percent of premature births) and fetal or neonatal death (1 percent each). (See "Clinical manifestations and diagnosis of intraventricular hemorrhage in the newborn" and "Management and complications of intraventricular hemorrhage in the newborn".)Risk factors for adverse outcomes included New York Heart Association class III or IV (table 1) or cyanosis at the baseline prenatal visit, left heart obstruction (aortic and/or mitral stenosis), smoking, multiple gestations, and the use of anticoagulants throughout pregnancy. (See "Use of anticoagulants during pregnancy and postpartum".)In the series of 90 pregnancies in women with congenital heart disease, spontaneous abortion occurred in 12.2 percent, a rate that was not different from the 12 to 15 percent rate in women without heart disease [16]. There were adverse neonatal outcomes in 28 percent of pregnancies, including preterm delivery (21 percent), small for gestational age (8 percent), intrauterine fetal demise (3 percent), intraventricular hemorrhage, and neonatal death (1.4 percent each). An adverse neonatal outcome was independently predicted by a basal left ventricular outflow gradient >30 mmHg (odds ratio 7.5).Issues related to survival of premature infants are discussed separately. (See "Incidence and mortality of the premature infant".)InheritanceOffspring of women with congenital heart disease are at increased risk of congenital heart defects. The risk of recurrent congenital heart disease varies with the specific parental defect [6,29]. The data according to defect are presented separately. (See "Pregnancy in women with congenital heart disease: Specific lesions".)The largest experience is from a series of 6640 pregnancies in which one parent or sibling had congenital heart disease. Recurrence in the fetus was detected by echocardiography [30] in 178 (2.7 percent), with recurrence of the same parental or sibling defect in approximately one-third. The incidence was similar whether the affected index case was the father, the mother, or a sibling.These results are qualified because only pregnant women referred for fetal echocardiography were included. Thus, the overall recurrence estimates may not be the same as those obtained from population-based studies:In a survey of 427 probands with congenital heart disease and their 837 children, the incidence of a cardiac anomaly in the offspring was 10.7 percent [31].In a collaborative study from Britain that evaluated 393 children of 727 parents, recurrence occurred in 4.1 percent of offspring and 2.1 percent of siblings [29]. The risk of recurrence was greater if the mother rather than the father had congenital heart disease (5.7 versus 2.2 percent).Similar findings were found in the prospective CARPREG report cited above [15]. There were 432 live births in mothers with congenital heart disease but no recognized genetic syndromes. Congenital heart disease was present in 7 percent.There also appears to be variation among lesions in the rate of recurrence of the same lesion in the parent or sibling, depending upon the specific defect. In the referral series cited above, the following were the three most frequent recurrent lesions [30]:Ventricular septal defect 55 percent concordance (17 of 31 recurrences)Coarctation of the aorta 13 percent (two of 15 recurrences)Hypoplastic left heart syndrome 33 percent (four of 12 recurrences)There are familial syndromes associated with specific disorders, such as atrial septal defect in the Holt-Oram syndrome, and a high rate of heritability with bicuspid aortic valve. (See "Classification of atrial septal defects (ASDs), and clinical features and diagnosis of isolated ASDs in children", section on 'Genetic disorders' and "Clinical manifestations and diagnosis of bicuspid aortic valve in adults", section on 'Genetics'.)PRECONCEPTION AND PRENATAL CAREPreconception or initial evaluationWhen possible, women should receive preconception assessment and counseling so that they are able to make informed pregnancy decisions. For women who have not had preconception counseling, a complete risk evaluation should occur at the first prenatal visit. Women with congenital heart disease should receive a preconception evaluation by a cardiologist with expertise in pregnancy and congenital heart disease. Risk assessment should involve a focused evaluation of the risk of pregnancy for the mother and baby. Many women with heart disease are unaware of the risks of pregnancy, and patient education is an important aspect of the preconception assessment [32]. (See "The preconception office visit" and "Initial prenatal assessment and first trimester prenatal care".)Preconception (or initial prenatal if the patient presents during pregnancy) evaluation should include a detailed history, information on prior interventions (surgical and percutaneous), symptom status, a complete physical exam, a 12-lead electrocardiogram, a transthoracic echocardiogram, and an assessment of functional status (which may include exercise testing). A transthoracic echocardiogram is important to determine the type and severity of cardiac lesions, ventricular size and function, assessment of valve function, and pulmonary pressures. Valvular or vascular gradients may increase during pregnancy and should be interpreted accordingly. (See "Pregnancy and valve disease".)Intervention prior to pregnancyOne of the best ways to simplify medical management during pregnancy is to perform indicated cardiac intervention (surgical or percutaneous) before conception. Successful cardiac intervention may improve fertility, may enable the mother to better tolerate the physiologic changes of pregnancy, can eliminate the fetal risk from maternal cyanosis, and benefits the subsequent health of mother and child. Women with congenital heart disease who have indications for cardiac intervention are generally advised to proceed with intervention prior to pregnancy (eg, percutaneous aortic balloon valvuloplasty for asymptomatic severe aortic stenosis to reduce maternal and fetal risks). However, the decision is much more complex when a valve replacement is required and a detailed discussion on the risk and benefits of bioprosthetic and mechanical valve options must be discussed with the patient. (See "Pregnancy and valve disease", section on 'Interventions prior to pregnancy'.)In contrast, cardiac surgery during pregnancy should be minimized or avoided [33-36]. The maternal risks are about the same as those in nonpregnant women [33,34], but cardiopulmonary bypass during pregnancy incurs risk for the fetus [33-37]. (See "Pregnancy and valve disease".) Prenatal carePrenatal care should include patient education concerning the patients responsibilities and the expected course of pregnancy and delivery. General recommendations for initial prenatal assessment and for prenatal care are discussed separately. (See "Initial prenatal assessment and first trimester prenatal care" and "Prenatal care (second and third trimesters)".)The frequency of prenatal follow-up depends upon the severity of heart disease (see 'Modified WHO classification' above): For class I conditions, cardiology follow-up during pregnancy may be limited to one or two visitsFor class II conditions, follow-up every trimester is recommendedFor class II to III conditions (depending on the individual), cardiology follow-up ranging from every trimester to monthly is recommended. For class III conditions, at least monthly or bimonthly cardiology follow-up during pregnancy are recommended. Expert counseling is required and this may include consideration of alternatives to pregnancy. Intensive specialist cardiac and obstetric monitoring are needed throughout pregnancy, childbirth, and the puerperium. For class IV conditions, pregnancy is contraindicated. If a woman presents with a lesion in this class early in pregnancy, termination should be discussed. If pregnancy is terminated, reparative surgery for high risk valve and/or aortic disease should be performed before another attempt at pregnancy. If pregnancy continues, care as for class III with monthly or bimonthly cardiology follow-up at a minimum. Pulmonary edema and marked peripheral edema should be distinguished from the normal physiologic edema of pregnancy. The peripheral edema typically seen during pregnancy does not connote excess risk and is due to an increase in total exchangeable sodium and water and inferior vena caval compression. Diuretics are not indicated and sodium restriction is not helpful for physiologic edema. (See "Renal and urinary tract physiology in normal pregnancy".)The value of antepartum oxygen in cyanotic women is questionable. There is little evidence that oxygen benefits the mother, and there is no evidence that a favorable effect is exerted on a growth-restricted fetus, even though administration of high levels of inspired oxygen may raise the arterial oxygen saturation [38]. Antepartum oxygen administration is not recommended. Other aspects of management of cyanotic congenital heart disease are discussed separately. (See "Medical management of cyanotic congenital heart disease in adults".)Hemoglobin levels decline modestly during healthy pregnancy so lower hemoglobin levels are used to identify anemia during pregnancy. (See "Hematologic changes in pregnancy", section on 'Anemia'.) Routine administration of iron supplements beyond standard prenatal multivitamins should be avoided, particularly in cyanotic patients. Patients with right-to-left shunts are erythrocytotic because of a hypoxia-driven increase in erythropoietin production. (See "Medical management of cyanotic congenital heart disease in adults", section on 'Erythrocytosis and anemia'.) Given the risk of thromboembolism during pregnancy, clinical follow-up should include careful surveillance for signs and symptoms of venous thromboembolic disease. Hypercoagulability is of particular concern for women at risk for thrombosis related to prosthetic heart valves, atrial fibrillation, or previous thromboembolic events. Such patients are candidates for anticoagulation. Considerations in choosing an anticoagulation regimen should include adverse fetal effects (eg, warfarin embryopathy) in the first trimester, bleeding risk, and the risk of thrombosis on the prosthetic valve. (See "Deep vein thrombosis and pulmonary embolism in pregnancy: Prevention" and "Use of anticoagulants during pregnancy and postpartum" and "Management of pregnant women with prosthetic heart valves".) Exercise encroaches upon the limited reserve of the pregnant woman with heart disease. Strenuous physical activity should therefore be avoided. (See "Exercise during pregnancy and the postpartum period: Practical recommendations".)Management of arrhythmias during pregnancy is discussed separately. (See "Supraventricular arrhythmias during pregnancy" and "Ventricular arrhythmias during pregnancy".)Fetal evaluationWomen with congenital heart disease should be offered fetal echocardiography in the 19th to 22nd week of pregnancy [12]. (See "Fetal cardiac abnormalities: Screening, evaluation, and pregnancy management".) PREGNANCY TERMINATIONThe option of pregnancy termination should be discussed with women in whom gestation represents a major maternal or fetal risk. The first trimester is the safest time for elective pregnancy termination, which should be performed in-hospital, rather than in an outpatient facility, so that all emergency support services are available. The general principles to consider when a termination procedure is planned include:The patient's cardiologist, an anesthesiologist, and the obstetrician/gynecologist who will perform the procedure should confer prior to the termination.Endocarditis prophylaxis is not consistently recommended [39], but treatment should be individualized. (See "Antimicrobial prophylaxis for bacterial endocarditis".) Gynecologists routinely advise antibiotic prophylaxis to prevent postabortal endometritis, which occurs in 5 to 20 percent of women not given antibiotics [39-41]. (See "Overview of pregnancy termination", section on 'Antibiotic prophylaxis'.)Dilatation and evacuation can be performed safely in both the first and second trimesters. (See "Overview of pregnancy termination", section on 'Choice of technique'.)If surgical evacuation is not feasible in the second trimester, protocols for second trimester induction abortion typically involve a prostaglandin (PG), usually misoprostol (PGE1), and may utilize mifepristone (an antiprogestin). Misoprostol and mifepristone appear to have minimal cardiovascular effects [42-45]. (See "Overview of pregnancy termination".) Older pregnancy termination techniques (PGE2, PGF, saline), which are no longer used, have been associated with serious adverse cardiac effects. MANAGEMENT OF LABOR, DELIVERY, AND THE POSTPARTUM PERIODEndocarditisThe rate of endocarditis was evaluated in retrospective review published from 1985 to 2006 that described the outcomes of 2491 pregnancies in women with structural congenital heart disease [6]. The rate of endocarditis was 0.5 percent during 1372 completed pregnancies among women with congenital heart disease [6]. However, other puerperal infections and antibiotic prophylaxis for this population were not disclosed.High rates of both maternal and fetal mortality (22 and 15 percent, respectively, in a review of 67 cases) have been reported for endocarditis during pregnancy [46]. However, most of the data came from individual case reports and are subject to selection bias.Guidelines for endocarditis prophylaxis are discussed separately. (See "Antimicrobial prophylaxis for bacterial endocarditis", section on 'Vaginal or cesarean delivery'.)LaborIn women with functionally mild unrepaired congenital heart disease, and in women who have undergone successful cardiac surgery without major residua, the management of labor and delivery is the same as for normal pregnant women, except for potential increase in risk of infective endocarditis.Pregnant women with unrepaired or postoperative congenital heart disease who are considered functionally normal are allowed to go into spontaneous labor. However, when there are concerns about the functional adequacy of the heart and circulation, labor should be induced under controlled conditions if there are no obstetrical contraindications to vaginal delivery. The timing of induction is individualized, taking into account the gravida's cardiac status, inducibility of the cervix, and probability fetal lung maturity as determined by gestational age and/or amniocentesis. Long inductions in women with an unfavorable cervix should be avoided.Induction of labor in gravidas with a favorable cervix usually requires only oxytocin administration and artificial rupture of the membranes. An unfavorable cervix can be ripened by a variety of methods. The softened, dilated cervix is more responsive to the subsequent induction of labor. (See "Techniques for ripening the unfavorable cervix prior to induction" and "Induction of labor".)The method of choice for cervical ripening may vary with the clinical setting. Mechanical methods are preferable in the patient with cyanosis where a drop in systemic vascular resistance and/or blood pressure would be detrimental. If a mechanical method is not possible, we favor misoprostol. A mechanical method, such as a Foley catheter, is favored due to concerns of potential adverse effects from pharmacologic agents for cervical ripening. However, there is a theoretical risk of infection from introduction of a foreign body. While there is no categorical contraindication to misoprostol or dinoprostone, there is a theoretical risk of coronary vasospasm and a low risk of arrhythmias. Dinoprostone appears to have more profound effects on blood pressure and is contraindicated in the presence of cardiovascular disease. During labor, the gravida should be in a lateral decubitus position to minimize uterine compression of the abdominal aorta and inferior vena cava, and thus to attenuate the hemodynamic fluctuations associated with major uterine contractions in the supine position. The fetal head should be allowed to descend to the perineum in response to the forces of labor, unassisted by maternal pushing, in order to avoid the undesirable circulatory effects of the Valsalva maneuver. Delivery can then be assisted by low forceps or vacuum extraction. (See "Maternal cardiovascular and hemodynamic adaptations to pregnancy".)Anesthesia and hemodynamic monitoringAnesthesia and hemodynamic monitoring for labor and delivery for high-risk cardiovascular disease is discussed separately. (See "Anesthesia for labor and delivery in high-risk cardiovascular disease: General considerations" and "Anesthesia for labor and delivery in high-risk cardiovascular disease: Specific lesions".) Fetal monitoringContinuous electronic fetal heart rate monitoring is recommended during labor. (See "Intrapartum fetal heart rate assessment".) Reductions in uterine blood flow and placental oxygen delivery typically occur during uterine contractions, but the fetus usually extracts enough oxygen to meet its needs. Fetal hypoxemia may occur with complications such as abruptio placentae, cord compression, maternal hemodynamic instability, or fetal growth restriction. Oxygen therapyOxygen is often administered during labor, especially in cyanotic women. However, maternal benefit has not been demonstrated, and it is not clear whether and to what extent maternal oxygen administration increases fetal PaO2. Transcutaneous fingertip oximetry is sufficient for monitoring maternal oxygenation.Preterm laborPreterm labor is a major concern, especially in cyanotic pregnant women whose fetuses are likely to be immature. Pharmacologic inhibition of uterine contractions (tocolytic therapy) may involve indomethacin, nifedipine, a beta adrenergic agonist, or atosiban, an oxytocin receptor antagonist. Potential complications of beta adrenergic agonist therapy include volume expansion and increased maternal heart rate, which can result in heart failure [47]. Nifedipine or indomethacin are generally the preferred agents. Nifedipine may be harmful in patients with significant aortic stenosis or cyanotic congenital heart disease. (See "Inhibition of acute preterm labor".)Role of cesarean deliveryFor the pregnant woman with a functionally significant congenital cardiac malformation, regardless of whether or not there has been surgical repair, the anticipation and management of labor, delivery, and the puerperium are crucial if risk is to be minimized. There is consensus that cesarean delivery should be reserved for obstetrical indications, such as breech presentation, failure to progress, placenta previa, or some abnormal fetal heart rate patterns. (See "Cesarean delivery: Preoperative issues", section on 'Indications and contraindications'.)The risks of cesarean delivery in such women include:General anesthesia that incurs the risk of hemodynamic instability associated with intubation and the anesthetic agent.Blood loss of at least twice as with vaginal deliveryIncreased risks of wound and uterine infections and postoperative thrombophlebitisIncisional bleeding in patients on anticoagulants and in cyanotic gravidas who have inherent coagulation defectsEndocarditisRoutine antimicrobial prophylaxis for bacterial endocarditis is not recommended in most women with congenital heart disease during pregnancy and delivery [48,49]. However, we agree with the suggestion in the 2008 American College of Cardiology/American Heart Association guidelines for the management of adults with congenital heart disease that in select high-risk patients (such as those with completely repaired congenital heart defects with prosthetic material or device during the first six months after the procedure, unrepaired cyanotic congenital heart disease [including those with palliative shunts and conduits], repaired congenital heart disease with residual defects at the site or adjacent to the site of the prosthetic device, or prosthetic heart valves); it is reasonable to consider antibiotic prophylaxis before vaginal delivery at the time of membrane rupture [50]. (See "Antimicrobial prophylaxis for bacterial endocarditis", section on 'Vaginal or cesarean delivery'.)The rate of endocarditis was evaluated in a retrospective review published from 1985 to 2006 that described the outcomes of 2491 pregnancies in women with structural congenital heart disease [6]. The rate of endocarditis was 0.5 percent during 1372 completed pregnancies among women with congenital heart disease [6]. However, other puerperal infections and antibiotic prophylaxis for this population were not disclosed.High rates of both maternal and fetal mortality (22 and 15 percent, respectively, in a review of 67 cases) have been reported for endocarditis during pregnancy [46]. However, most of the data came from individual case reports and are subject to selection bias.Postpartum careAfter expulsion of the placenta, bleeding is reduced by uterine massage and administration of intravenous oxytocin, which should be infused slowly (less than 2 U/min) to avoid hypotension. Meticulous leg care, elastic support stockings, and early ambulation are important preventive measures that reduce the risk of postpartum thromboembolism. In cyanotic gravidas, heparin reinforces the intrinsic hemostatic defect(s) and may result in dangerous and even fatal hemorrhage [1]. Accordingly, heparin should be used with caution and restricted to patients identified to be high risk for venous thromboembolism. This does not apply to patients with prosthetic heart valves in whom anticoagulation is required. (See "Management of pregnant women with prosthetic heart valves", section on 'Anticoagulation during pregnancy for women with mechanical heart valves'.)BreastfeedingBreastfeeding a newborn is fatiguing and is associated with a low risk of mastitis with bacteremia. As a result, some women with symptomatic congenital heart disease who might otherwise prefer breastfeeding choose to bottle-feed.FERTILITYThere are two main fertility issues in women with congenital heart disease: menstrual patterns and contraception.Ovarian functionOvarian function in women with congenital heart disease is an important concern. Whether or not ovarian function varies with the type of heart defect, and how reparative surgery affects ovarian function, remain largely unknown. In a report of 98 women (mean age 33), those who were cyanotic had a delay in onset of menstruation (by about one year) and an increased incidence of abnormally short or long cycle lengths. Women with acyanotic congenital heart disease had menstrual patterns similar to normal controls [51].Abnormal menstrual patterns in cyanotic women are believed to represent a chronic anovulatory state related to dysfunction of the hypopituitary-ovarian axis or to abnormal uterine hemostasis in response to chronic hypoxemia and erythrocytosis. It is not known if there is an age beyond which reparative cardiac surgery is unlikely to be followed by normal ovarian function, especially in cyanotic women. For women with subfertility due to anovulation, standard treatment such as clomophine is not contraindicated. Chronic anovulation predisposes to endometrial hyperplasia and carcinoma. (See "Endometrial carcinoma: Epidemiology and risk factors", section on 'Chronic anovulation'.)ContraceptionWomen with congenital heart disease should be given information about contraception and the potential risks associated with pregnancy [32]. The same contraceptive methods available to normal healthy women are generally applicable to those with congenital heart disease [52]. However, women with congenital heart disease often do not know the most appropriate method of contraception or are given incorrect advice [53]. Factors to consider are whether a reversible contraceptive method or sterilization is preferable, the efficacy of various methods, patient-specific factors that affect compliance (table 2), and medical issues that affect the risk-benefit profile of various methods. The Centers for Disease Control have published guidelines for estimating the risk versus benefit of use of contraception in women with medical disorders (table 3). (See "Overview of contraception".)Briefly:Barrier methods include condoms for males or the diaphragm with spermicide for females. Although these methods are generally less effective than other techniques, they pose virtually no risk of complications. In women needing to avoid pregnancy due to their cardiac status, these methods should be avoided due to their high failure rate (18 percent for male condom).An intrauterine device (IUD) is an option for acyanotic or mildly cyanotic women who want a reversible method of contraception and are at low risk of acquiring a sexually transmitted infection. (See "Intrauterine contraception (IUD): Overview".)The higher dose levonorgestrel-releasing intrauterine device (Mirena) has the advantage of reducing menstrual blood loss by 40 to 50 percent but may induce amenorrhea. It is effective for five years. A lower dose device is also available and is effective for three years. Systemic hormonal effects are minimal.A copper containing IUD has the advantage of lasting for at least 10 years, hence, less need to change the IUD and thus minimizing risk of infection. It will not interfere with medication metabolism, it causes no hormonal side effects, and has few contraindications related to medical conditions. It is not recommended in women who are anemic or cyanotic with hematocrit levels above 55 percent because intrinsic hemostatic defects increase the risk of excessive menstrual bleeding, which is more common with the copper containing IUD than the levonorgestrel-releasing IUD. Combination estrogen-progestin contraceptives (pill, patch, ring) can be used in women at low risk for thromboembolic complications, ie, no pulmonary hypertension and no surgical baffles, such as those with uncomplicated valvular disease (table 3). The usual ethinyl estradiol dose is 20 to 35 mcg. The 20 mcg dose may have fewer thromboembolic complications. (See "Overview of the use of estrogen-progestin contraceptives" and "Risks and side effects associated with estrogen-progestin contraceptives".)Progestin-only contraception can be given, using the levonorgestrel-releasing IUD, injections of depot medroxyprogesterone (eg, Depo-Provera), pills (eg, Micronor tablets, Nor-QD, or generics), or the etonogestrel implant (Nexplanon). Depo-Provera is inappropriate for patients with heart failure because of its tendency to cause fluid retention. (See "Overview of contraception", section on 'Issues to consider when beginning hormonal contraception'.)Tubal occlusion is not reversible but can be accomplished safely, even in relatively high-risk women. The risk may be even lower with the minimally invasive hysteroscopic technique [54]. (See "Hysteroscopic sterilization" and "Surgical sterilization of women".) Vasectomy for the male is an equally efficacious option that incurs no maternal risk. Recommendations for appropriate contraception for women with heart disease, including congenital heart disease, are reviewed in an American Heart Disease guideline statement on best practices in managing the transition to adulthood for adolescents with congenital heart disease [55].RecommendationsFor women with cyanotic congenital heart disease and pulmonary vascular disease, tubal ligation, etonogesterel implant (Implanon), or an intrauterine device are the safest and most effect options for preventing pregnancy. (See "Etonogestrel contraceptive implant" and "Surgical sterilization of women" and "Intrauterine contraception (IUD): Overview" and "Overview of contraception".)Depo-Provera is inappropriate for patients with heart failure because of its tendency to cause fluid retention. Oral contraceptives containing 20 to 35 mcg of ethinyl estradiol are considered safe in patients with a low thrombogenic potential and a low failure rate, provided that no dose is missed and provided the patient does not smoke [56].SUMMARYImproved surgical repair options have resulted in most women with congenital heart disease surviving to bear children. Despite these advances, congenital heart disease remains an important cause of maternal mortality and morbidity. (See 'Epidemiology' above.)Normal alterations in circulatory and respiratory physiology during pregnancy can have deleterious effects on the mother with congenital heart disease and on her developing fetus. (See 'Hemodynamic changes' above.)Pulmonary edema and marked peripheral edema should be distinguished from the normal physiologic peripheral edema of pregnancy. The edema typically seen during pregnancy does not connote excess risk and is due to an increase in total exchangeable sodium and water and inferior vena caval compression. Diuretics are not indicated and sodium restriction is not helpful for physiologic edema. (See 'Prenatal care' above.)Hypercoagulability is a particular concern in women at risk for thrombosis related to prosthetic heart valves, atrial fibrillation, or previous thromboembolic events or intracardiac shunts. Such patients are candidates for anticoagulation. Considerations in choosing an anticoagulation regimen should include adverse fetal effects (eg, warfarin embryopathy) in the first trimester, bleeding risk, and the risk of thrombosis on the prosthetic valve. (See 'Risk of thromboembolism' above and 'Prenatal care' above and "Use of anticoagulants during pregnancy and postpartum" and "Management of pregnant women with prosthetic heart valves".) We favor using the modified World Health Organization (WHO) risk classification for maternal risk assessment. (See 'Overview' above.)Modified WHO classification of risk according to maternal cardiovascular condition provides guidance regarding the frequency of prenatal cardiology and obstetric follow-up. (See 'Modified WHO classification' above and 'Prenatal care' above.)The following maternal conditions pose very high maternal and/or fetal risk during pregnancy: significant pulmonary arterial hypertension of any cause, severe mitral stenosis, severe aortic stenosis, bicuspid aortic valve with ascending aorta diameter >50 mm, Marfan syndrome with aorta dilated >45 mm, severe systemic ventricular systolic dysfunction (left ventricular ejection fraction