[ChuckElias]

Again, welcome to the forum.

A couple of things may be going on here. First, and most likey, is that the defender is putting her hands across the OOB line. This is a delay of the game. The first offense is a team warning and the second offense is a team technical foul. Don't let the defensive players reach through the OOB boundary until after the throw-in has been released.

The other thing that might be happening is less likely, but I'll mention it anyway. If the defender is holding her hands directly in the inbounder's face, this could be obstructing the vision of the inbounder and is a technical foul charged to the defender.

The easiest way to avoid that technical is to tell the inbounder to back up a little to get some space. If the gym is small and the inbounder physically can't back up, then instruct the defender to back up and don't let her creep back toward the inbounder.