The Behavioral Analysis Unit or the BAU, as "Criminal Minds" fans like to call it, will be short of two members once Season 11 rolls along.

Stars Jennifer Love Hewitt and A.J Cook are both pregnant so fans would not be able to see much of the two. While everyone's favorite BAU mom JJ will miss at least 5 episodes, Agent Kate Callahan will be gone for the whole of season 11. It is still not clear whether or not the actress will return for season 12.

The "Ghost Whisperer" star learned she was pregnant around the time the 10^th season was wrapping up and decided to leave the show to focus on her new baby.

On the other hand, AJ Cook's return would depend largely on when she gives birth, explains "Criminal Minds" producer Erica Messer. In an interview with Zap2it, Messer calculated the logistics of JJ coming back to the show once it starts shooting in July.

"If she has the baby at the end of July, we'll have to figure out how much time she'll want," Messer explains. "My guess is it will probably be the first five episodes.  

Working with a smaller team will prove difficult for the BAU team when they work on their cases so the producers are working on the idea of bringing back former agents. Another option is to continue with their "revolving door" approach when it comes to new agents.  

One agent that fans undoubtedly want to see back is Supervisory Special Agent Emily Prentiss.  It is an idea that has also been hinted at by actor Joe Mantegna, who plays Senior SSA David Rossi.

"Well, there's been talk of -- there's a chance Paget may make an appearance now and again," the 67-year-old Mantegna said, referencing Messer's TV Guide comment that it would be fun to have Prentiss back.