Even though Scarlett Johansson is about five months along in her pregnancy, she claims that her upcoming baby with fiance Romain Dauriac was a "surprise"!!

It wasn't that she wasn't trying for the baby, at least according Us Weekly. In fact, she knew about the baby for some time -- she just chose to wait for a bit before officially announcing the baby to the public. "She's about four months along. The baby was a welcome surprise... she's just excited to share the news!" a source told Us Weekly.

Indeed, some of Scarlett's co-stars and colleagues -- including director Jon Favreau -- think she's going to be a "wonderful" mother, according to The New York Daily News. "She's one of my favorite people because she's smart, she's talented, and she's really down to earth and a hard worker," he said. "I like a hard worker."

But Scarlett's pregnancy doesn't come without some complications. As many know, she's in the process of shooting Avengers 2, where she will reprise her role as the Black Widow. So, how will the baby affect the movie? According to Entertainment Weekly, we can expect the following four developments:

1. The film's production will be fast-tracked: though there's been no official confirmation about this option from Marvel, some are speculating that filming could begin the second Captain America: The Winter Soldier hits theaters on April 5.

2. Push back the shooting: this is a less viable option, but if Scarlett gets too far along, or there's problems in the pregnancy, it's an option they're going to have to take.

3. Stunt doubles: it wouldn't be the first time, and it wouldn't be the last, that stunt doubles were used in a blockbuster film.

4. Reduce her role: given that Black Widow is the only female Avenger, this reeks of sexism, but it wouldn't be the first time Hollywood took the sexist route.