TOPLINE

Pregnant women with preexisting cardiomyopathy managed in the UK had relatively few cardiac complications and no maternal deaths; heart failure occurred in about 1 in 10 women, and a small proportion needed ICU admission, and nearly 1 in 5 infants required neonatal unit care.

METHODOLOGY

• Using data from the UK Obstetric Surveillance System, researchers conducted a prospective cohort study between 2021 and 2024 to assess maternal, obstetric, and neonatal outcomes across cardiomyopathy subtypes among women with preexisting cardiomyopathy.
• The analysis included data from 210 pregnancies beyond 24 weeks of gestation in 209 women (mean maternal age, 31.5 years) with a known prepregnancy diagnosis of cardiomyopathy; of these, 206 were singleton pregnancies and four were twin pregnancies.
• Diagnoses were assigned after cross-checking clinician-reported categories with free-text notes: 104 women with dilated cardiomyopathy, 40 with hypertrophic cardiomyopathy, 24 with prior peripartum cardiomyopathy, 11 with arrhythmogenic right ventricular cardiomyopathy, and 31 with "other" cardiomyopathies.
• The researchers assessed maternal deaths, cardiac complications, delivery and birth outcomes, and neonatal unit admission.

TAKEAWAY

• No maternal deaths were reported among the 210 pregnancies. Heart failure developed in 10.5% of women during pregnancy. New arrhythmias occurred in 3.8% of women during pregnancy.
• Level 3 ICU admission was needed in 5.5% of women.
• Among singleton pregnancies with available data on the delivery mode, 57.1% were delivered by caesarean section, with no significant differences by diagnosis, and major haemorrhage (≥ 1000 mL blood loss) was reported in 9.6%.
• Preterm births were reported in 19.5% of babies, with no significant differences by diagnosis, and 20.0% of babies with recorded data were admitted to the neonatal unit.

IN PRACTICE

"All women with known cardiomyopathy should be offered preconception counselling, ideally from their pregnancy heart team in accordance with the most recent ESC [European Society of Cardiology] guidance," the authors wrote.

SOURCE

This study was led by Matthew Cauldwell, Department of Maternal Medicine, St George's Hospital, London, UK. It was published online on October 09, 2026, in BJOG: An International Journal of Obstetrics & Gynaecology.

LIMITATIONS

Data on women who miscarried or terminated pregnancies were lacking. Echocardiography was not carried out in a systematic way at any particular stage of pregnancy. The indications for caesarean delivery were not systematically recorded, limiting the interpretation of the high caesarean section rate.

DISCLOSURES

The study was supported by Heart Research UK. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.