If you go into your profile, there is a link that says "Invites". If you click on it it has the # of invites sent & accepted and the blurb
Invitations should only be sent to those who will respect the format of the site and who are interested in posting their work and commenting on others. For every accepted invitiation you send out, you get two additional invitations.
(invitation is spelled wrong by the way).
We do not want this function to be made available to our users.
p.s. We have Messages turned off by the way, but it does not control the invite.