Unfortunately there isn't much you can do to prevent miscarriages. Most** of the time it's a chromosomal abnormality that causes it. You definitely need to request to sit down and chat with your doctor because your hormone levels may be off or something and that could have caused it but most of the time it's nothing that can be controlled. You can get pregnant pretty soon after a miscarriage as long as your period has returned to normal and your doctor said its okay(some people have other issues after)