It's not even medieval - that was another continent. They're back at the original holt surrounded by humans who seem more like the Native Americans were at the time of Columbus. They're still tribal and nomadic and I'm assuming their medicine is still mostly herbs and prayers. It's a shame the story will almost certainly not spend much time with Shen-shen, not in the detail we're talking about. Sooooo, who's up for writing "Call the (Secretly Elfin) Midwife?"