Should you take Antibiotics before dental work with mitral valve?

Yes, but tell your dentist you are pregnant so an appropriate one can be prescribed. The consequences of not taking it do not bear thinking about. ----

Not related specifically to the pregnancy issue - but to the need for antibiotics if you have mitral valve prolapse. I used to take antibiotics before dental work. Guidelines have recently changed. Here's some important information from the American Heart Association. Note especially the bold text. The American Dental Association has basically the same information.

"Most people with mitral valve prolapse don't have symptoms, won't have problems and won't need treatment. However, those who have leaky (regurgitant) prolapsing valves are at increased risk of developing an infection of the lining of the heart or heart valve known as endocarditis. In the past, some people with MVP have been given antibiotics before certain dental or surgical procedures to help prevent an infection called bacterial endocarditis (BE). However, the American Heart Association no longer recommends routine antibiotics before dental procedures except for patients at the highest level of risk for BE, such as patients with a prosthetic cardiac valve, patients who have had BE before, or patients with specific types of congenital Heart disease. Also, the American Heart Association no longer recommends routine antibiotics to prevent BE in patients undergoing procedures of the gastrointestinal or genitourinary tract.

Medicine may be used in a small number of MVP patients with chest pain, angina pectoris or abnormal heart rhythms (arrhythmias)." Usually, amoxicillin is given before dental work when indicated. Mitral valve prolapse only requires antibiotic prophylaxis for dental work if there is a persistent murmur.