In cases of serious aortic valve disease, choosing a new heart valve is particularly difficult for young women who wish to become pregnant. A new Swedish registry study from Karolinska Institutet shows that a biological aortic valve provides good pregnancy and birth outcomes, even though the need for reoperation is more common than with a mechanical valve. The study is published in the Journal of the American College of Cardiology (JACC).
In cases of severe aortic valve disease, valve replacement surgery may be necessary, even for young women. There are mainly two options. Mechanical valves are very durable but require lifelong treatment with blood‑thinning medication, which can pose risks for both the woman and the foetus during a possible pregnancy. Biological valves do not require the same type of blood‑thinning treatment, but they wear out more quickly and may lead to the need for another operation later in life.
In the study, the researchers analysed women in Sweden aged 18-40 who had undergone aortic valve replacement between 1997 and 2024. A total of 251 women were included, of whom 93 received a biological valve and 158 a mechanical valve. The information was obtained from national quality registers and other health data registers and was followed over a long period.
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Contribute to better evidence for shared decisions
About half of the women who received a biological valve had at least one child during the follow‑up period, compared with just under one in ten of those who received a mechanical valve. For those with a biological valve, cardiovascular outcomes were generally good despite high risks of reoperation.
– Our results show that a biological valve is a reasonable option for women who are planning a pregnancy, although one must be aware of the risk of future reoperation. We hope that the findings can contribute to better evidence for shared decisions between doctor and patient, says Ruixin Lu , doctoral student at the Department of Molecular Medicine and Surgery, Karolinska Institutet.
Photo: Fotograf Ulf Sirborn
– It is encouraging that many women with a biological aortic valve can undergo pregnancy and childbirth. At the same time, we know that many of these young women will later need to be operated on again, as the valve wears out over time. In our continued research, we are examining how assessment and treatment can be improved ahead of their next heart operation, says Ulrik Sartipy , cardiac surgeon at Karolinska University Hospital and adjunct professor at the Department of Molecular Medicine and Surgery, Karolinska Institutet.
The researchers stress that the choice of valve must always be adapted to the individual patient’s situation and life plans.
The study is a national observational study based on Swedish health registers. It was conducted in collaboration between Karolinska Institutet and Karolinska University Hospital. The research was funded in part by the Swedish Heart‑Lung Foundation, Region Stockholm and foundations linked to Karolinska Institutet. The researchers report no conflicts of interest.
Publication
Aortic Valve Replacement in Women of Reproductive Age.
Lu, R, Dalén, M, Dismorr, M. et al. JACC. 1 July 2026,
doi.org/10.1016/j.jacc.2026.05.024
