Proper Medical Care Key to Safe, Uncomplicated Pregnancies in Women with Congenital Heart Defects

With expert medical care and counseling, most women with congenital heart defects (CHD) can safely become pregnant and give birth to healthy babies with few difficulties in a resource-rich, modern healthcare system, according to results from a population-based study published in the European Heart Journal.

But, although these women have relatively low maternal mortality rates, they do have significantly increased risks of maternal morbidity and neonatal morbidity/mortality compared with controls.

“During the last decades, we have witnessed an increasing number of adolescents with congenital heart disease (CHD) entering adulthood and now reaching reproductive age. Particularly CHD women with defects of moderate and severe complexity, aiming to start a family, are increasingly presenting to CHD centers and seek advice on potential maternal or neonatal risks associated with pregnancy,” wrote first author Astrid Elisabeth Lammers, MD, of the University Hospital Münster, Germany, and fellow researchers.

Using data from one of the largest German health insurance companies, Lammers and colleagues identified all pregnancies in women with CHD between 2005 and 2018, whom they matched with healthy, age-matched controls without CHD.

In all, there were 7,512 pregnancies in 4,015 women with CHD, and these were matched with 11,225 pregnancies in 6,502 women in the non-CHD control group. Mothers were managed by pediatric and adult cardiologists, gynecologists, and general practitioners, in addition to going to regional and national adult CHD centers with access to appropriate counseling.

More cesarean deliveries occurred in CHD patients compared with controls (40.5% versus 31.5%, respectively; P<0.001). No excess mortality occurred in either group (0% for both), and while maternal complications were rare, women with CHD had a significantly higher rates of cerebral ischemia compared with healthy controls (1.13% versus 0.17%, respectively), heart failure during pregnancy (0.84% versus 0.03%), and cardiac arrhythmias during pregnancy (0.82% versus 0.12%) (P<0.001 for all).

Upon multivariate logistic regression, Lammers et al found the following to be significant predictors of adverse neonatal outcomes (P<0.05 for all):

• Maternal defect complexity.
• Arterial hypertension.
• Heart failure.
• Previous fertility treatment.
• Anticoagulation with vitamin K antagonists.

Neonatal mortality was also low overall, but significantly higher in the ACHD group compared with controls (1.40% versus 0.40%, respectively; P=0.001), as was infant mortality in the first month of life (0.83% versus 0.22%). Neonates born to CHD mothers also were more likely to be of low/extremely low birth weight (7.54% and 1.01%, respectively, versus 5.25% and 0.53% in controls) or extreme immaturity (10.66% versus 7.12%, respectively; P<0.001), and require resuscitation and mechanical ventilation more often than non-CHD neonates (8.74% versus 3.57%; P<0.001 for both).

Babies born to mothers with CHD also were more likely to have CHD compared with babies of mothers without (18% versus 3%, respectively). In these infants, the recurrence of CHD was 6.1 times higher compared with controls (P<0.0001), with 17.7% versus 2.9%, respectively, having a congenital heart disease code recorded, and 5.95% and 0.39% requiring heart surgery with heart-lung machine support by 6 years of age.

“This population-based study illustrates a reassuringly low maternal mortality rate in a highly developed healthcare system. Nevertheless, maternal morbidity and neonatal morbidity/mortality were significantly increased in women with ACHD and their offspring compared to non-ACHD controls highlighting the need of specialized care and pre-pregnancy counselling,” concluded Lammers et al.

In a press release, Lammers added: “Our findings should help to inform mothers-to-be with congenital heart disease what to expect in terms of neonatal complications and to direct them to appropriate care providers if they wish to start a family. Counselling is a very important part of the care of every woman with a congenital heart defect and should start at an early age. It appears to work in developed countries such as Germany, as suggested by the lack of deaths among the mothers. This is probably due to avoiding very high-risk pregnancies and appropriate management of pregnancy.”

In an accompanying editorial, Karishma P. Ramlakhan, MD, and Jolien W. Roos-Hesselink, MD, PhD, of Erasmus MC, University Medical Center Rotterdam, The Netherlands, noted that the most important result of this “well-performed and excellently written study” was the absence of maternal mortality in women with CHD.

“This is unexpected and fantastic news,” they wrote, adding that another important finding is the high risk of these infants having CHD.

“In conclusion, the study by Lammers et al. is an excellent and clinically relevant contribution to the existing literature on pregnancy in women with congenital heart disease. The study shows that a good healthcare system, a multidisciplinary approach, and decisive pre-pregnancy counseling are effective in achieving safe pregnancies. Pre-pregnancy counseling with an individualized approach is a crucial step in this process, because both maternal and perinatal outcomes vary greatly by the complexity of maternal illness, and further studies dedicated to specific congenital diagnoses remain warranted,” they concluded.

Limitations of this study include its observational nature, the inability to identify associations between mechanical valves and anticoagulative therapy and neonatal complications, favorable maternal outcomes that led to a lack of maternal adverse outcomes with which to develop a risk model, and a bias towards women who were not advised against pregnancy or decided to pursue pregnancy.

1. When supported with expert medical care and appropriate counseling, most women with congenital heart defects (CHDs) can safely become pregnant and give birth to healthy babies with few or minor problems.

2. Maternal morbidity and neonatal morbidity/mortality were significantly increased in women with adult CHD and their offspring compared to non-CHD controls, which highlights the need for specialized care and pre-pregnancy counseling.

Liz Meszaros, Deputy Managing Editor, BreakingMED™

Cat ID: 41

Topic ID: 83,41,497,730,914,41,138,192,925