The 'Teenage Mutant Ninja Turtles' actress has joked husband Brian Austin Green is no longer allowed "anywhere near" her after unexpectedly falling pregnant with sons Noah, now 19 months, and Bodhi, two months.
Speaking on 'The Ellen DeGeneres Show' yesterday (05.05.14), she said: "The first one wasn't planned either and I mean, we can't let Brian near me anymore."
The 27-year-old beauty also praised the host as a "fertility good luck charm" as her pregnancies came so close to previous appearances on her show.
She said: "The first time I was here I was pregnant and no one knew it and then the second time I just had my baby, but I got pregnant again so you're sort of like a fertility good luck charm."
Because Megan - who showed off the first pictures of Bohdi on the show - had just begun filming 'Teenage Mutant Ninja Turtles' when she found out she was pregnant with her youngest son, she admits her first trimester was difficult as she was constantly fighting nausea while shooting action scenes.
She said: "I got pregnant with Bodhi two weeks into filming 'Ninja Turtles', which is an action movie and requires a lot of running and jumping and stunts and so I spent the entire...anyone that's been pregnant know your first trimester can be pretty rough and you're nauseous all day long.
"So I spent the whole shoot basically [being nauseous], the producers would come see me in the morning in the make-up trailer and I would be clinging to a box of saltines and we had, we kept pickles in the refrigerator for me and I was just constantly on the verge of vomiting.
"[I was] running, jumping, fighting. Saying things like, ''Show me what you got Shredder!' Stuff like that, so all the fun things you want to do when you're pregnant."