I didn't understand this part.She isn't pregnant at all, her braid has spawned an inner braid that happens to be inside her stomach.
On the Adriana route. The dog did it. Doggystyle, to be exact.
On the Haley + Sandra route...um...well you see. Haley wanted to explain how babies are made to Sandra, so she decided to be a surrogate mother to someone at work. That someone isn't Sandra either! I swear....