I think you would take the form of the person at the time their hair was collected. What canon evidence is there to support this? Well, none, but it's just how I think it would work.Originally Posted by OliveOil_Med
So, if you plucked a woman's hair before she became pregnant, you will take her non-pregnant form. And if you have a hair taken from someone who had died, you can still look like him/her. However, if you were to take a hair from a rotting corpse, you might just end up looking like a rotting corpse.
Here's a question: What if the person you want to look like was tragically hit by a cannonball and blown to little pieces? If you were to take a hair from his/her severed head, would the Polyjuice Potion give you the appearance of the person when they were whole, or would you end up being a writhing collection of red rags?
Tim the Enchanter