Yes they can. It is possible to do that if there is reason for the surgery.
Yes. Vascular surgeons can assess the risk of vascular problems in pregnancy (such as deep vein thrombosis and varicose veins) but only the vascular issues.
Yes. Vascular surgeons might help in reducing the symptoms associated with venous distention and varicose veins. They may also be able to help manage a patient with a history of DVT who is now at increased risk because of their pregnancy.