If in the 9th month, that means she is not allowed to travel on an airplane.

Get medical certificate stating that, buy here a ticket back dated two weeks or one month after expiry date.

By that date she should be able to fly along with newborn.

Submit the all papers to the Captain, if possible let an Arabic person to talk to him.

If that was OK, don't forget to immediately to:

- Get birth certificate.
- Add the newborn to your wife passport.
- Add the newborn to your wife visit visa.

By the way, how long she is here in Qatar? and how many time you brought here her with a visit visa?

Good luck