Revealing mistake: In the opening scene the Doctor and Donna are speaking over the phone. The purple phone Donna is holding shows the slot where a cable should be plugged in, but there is none. (00:00:25)
Suggested correction: This shouldn't be considered a mistake. While it's true in real life this phone has a slot for a cable, they're on an alien planet and this is unknown technology. In-universe there's no way of knowing what that slot is for, and there's no reason to think the phone needs to be plugged into anything.
Continuity mistake: When Donna starts fiddling with the Adipose necklace she stole, this causes an Adipose to be created out of Stacey's fat cells. When this begins, Stacey is in the upstairs bathroom applying lip gloss, and she's holding the applicator wand when her stomach begins to move. When she pulls up her shirt to look at her distending stomach in the mirror, the lip gloss wand is gone. (00:07:15)
Suggested correction: Actually, it looks like she finished putting on lip gloss and put the lid with the applicator back on just before she starts feeling queasy from the impending Adipose birth.
