Obviously scarier pregnant, as the writers were crapping bricks at the thought of treating her as a character with agency like they had previously. Note that before the pregnancy reveal (even while technically pregnant in "Missing") Teyla = kickass warrior-diplomat who's always competent and resourceful and has to be outnumbered like 20 to 1 for there to be any dramatic tension. After the pregnancy reveal, Teyla = damsel in distress who gets condescended to constantly and is reduced to urging others to action rather than doing anything proactive herself, even when being marched around by nameless extras who look like they've overdosed on thorazine.