Maternal and neonatal complications in women with congenital heart disease: results from a nationwide analysis including 7,231 pregnancies
Authors: Diller G.P , Lammers A.E , Enders D , Baumgartner H 
Published: November 2020

Abstract

Background
The number of adult patients with congenital heart disease (ACHD) is increasing. Many ACHD women aim to start a family and require adequate pre-pregnancy counselling and pregnancy care. Limited population-based data on maternal and neonatal outcome and complications are available.

Purpose
We analysed the association between ACHD and maternal or neonatal outcomes based on data from one of the largest German Health Insurance Companies (approx. 9 million members). All pregnancies in women with ACHD and an age-matched non-congenital control group were included. The data covered all pregnancies and deliveries (in and out of hospital) between 2005 and 2018.

Results
The study population comprised 25,528 ACHD patients of childbearing age. Overall, 7,231 pregnancies occurred in 3,868 ACHD women (mean age at delivery 30.7±5.4 years). An age matched group of 6,513 women without ACHD (11,247 pregnancies, mean age 30.0±5.6 years) served as controls. Miscarriages/abortions occurred in 2,501 (34.6%) and 3,586 (31.9%) cases in the ACHD and non-ACHD cohort, respectively. Overall, there were 4,551 successful deliveries (99.5% in hospital) and 59 stillbirths in ACHD patients. Cesarean deliveries (CS) were significantly more common in ACHD patients (40.4% vs. 31.5% in the control group; p&lt;0.0001) and the CS rate increased with disease complexity (Bethesda class I/II/III: 39.2/42.3/44.4%; p=0.035). There was one successful maternal resuscitation in each group, but no maternal deaths during pregnancy and up to 90 days postpartum. ACHD patients had a higher rate of maternal cerebral complications (1.0% vs. 0.17%; p&gt;0.0001) compared to the control group. Neonatal mortality was low but significantly higher in the ACHD group (0.76% vs. 0.22% within the first 30 days of life; p&lt;0.0001). Neonates to ACHD mothers were also significantly more often afflicted by low or extremely low birth weight or extreme immaturity (p&lt;0.0001), and required resuscitation (1.04% vs. 0.34%; p&lt;0.0001), mechanical ventilation (8.7% vs. 3.5%; p&lt;0.0001) or blood transfusions (3.11% vs. 1.08%; p&lt;0.0001) significantly more often compared to offspring from non-ACHD mothers. In addition, recurrence of congenital heart disease was 6.1 times higher in infants to ACHD mothers compared to controls (p&lt;0.0001). Overall, 5.87% of all children born to ACHD mothers required cardiac surgical procedures in the first 6 years of life compared to only 0.39% of children to non-ACHD mothers (p&lt;0.0001).

Conclusion
Our analysis confirms that maternal morbidity and neonatal morbidity and mortality are significantly increased in women with ACHD and their offspring compared to non-ACHD controls. Although, maternal mortality appears limited in high resource health care systems, the elevated maternal complication rate and particularly the high mortality and complication rate in neonates justifies specialized care to address specific risks and requirements of the condition.

Funding Acknowledgement
Type of funding source: None