Everyone on here complains that they have to wait a certain amount of time to get into the doctors to get a scan. At my OBGYN's office they allow you to make an appointment whenever you want or need. You don't have to wait until you are a certain amount of weeks or wait until a certain amount of weeks after your last scan. It makes no sense because I have never heard of someone having to wait until I got on this site. Even my sister and friends went into their scans whenever they pleased.