The tattoo on Holly's right shoulder blade disappears when she wears a brown bikini during the Aquarium scene.
When Rosie takes her pregnancy test, the box shows a First Response digital test. When she puts the test down, it's a standard test.
When Gary and Ramsey are racing with golf carts, Ramsey's foot moves from the dashboard to the floor and back between shots.
When Holly is watching herself in the mirror her dolphin tattoo is on the left shoulder. On the couch a few seconds later when Alex kisses Holly's shoulder the dolphin tattoo has moved to the right shoulder.
When Rosie and Marco are in the hospital, Rosie is clearly wearing make-up, despite the fact that she woke up in the middle of the night prior to going to the hospital.
During the ultrasound scene, all of the couples are told the sex of their embryos. However, all of the pictures are side views, which wouldn't show the genitalia.