Mitral valve stenosis. Solutions if any?

My sister is currently suffering from mitral valve stenosis due to heavy calcium depositions and due to this she will have to go for valve replacement surgery but doctors are saying as she is quite young hence she should go for metallic valve but once she will start taking blood thinner medicines after the surgery she will have difficulty in delivering baby. But there is another option which is tissue valve, if she will have that in that case it will be easy to deliver a baby without any issue but the problem with tissue valve is that it can last upto max 10 years and after that she will have to go another surgery which will be more complex. Now my question is, if she will have metallic valve then will she be still be able to deliver a healthy baby without any complications? Is there any way to still deliver a child without any major complications? And what are the cost of those solutions if any?