It would seem there are reputable sources declaring that Mila Kunis is indeed pregnant. I have to ask though, is this really important to you? I think it's great when women have children and I watch TV and film a lot, sometimes Mila Kunis is an actor in these viewings, but I couldn't care less if she is pregnant or not.
I do not believe that Mila Kunis is pregnant. I do not believe that she is pregnant because the news did not come directly from Mila Kunis. The announcement was made by an identified source and has not been officially confirmed. There also have not been any pictures of her being pregnant.
Magazines are notorious for jumping the gun on rumors in Hollywood. They make outrageous claims about celebrities all the time. If a female celebrity is leaving a building in a big coat with a bag in front of her, it's automatically assumed she's pregnant. The couple admitted to their engagement publicly. In due time they'll confirm or deny the news. As for how mum they've been, one can assume it's another gossip magazine fail.
No, Mila Kunis is not pregnant, because she is just doing this to make herself more popular. Mila Kunis just wants to be in the papers and make herself famous. She found a way to do so that is hard to criticize. She will say that she is, but she is just saying so for attention.