Julie Benz (Darla) said the following of playing a heavilt pregnant vampire:

“I had to wear a leotard that was stuffed with a pillow and it was pretty uncomfortable, but I think the biggest challenge during all those pregnant scenes was being on camera without any make-up on. That’s pretty much a challenge when you’re an actress, just to go on camera completely raw.

Yeah, I really felt at that point she was pretty strung out. Her whole world was rocked. She never thought she could get pregnant and then all of a sudden she’s carrying this child and she’s experiencing this soul for the first time in four hundred years. [There’s] the realisation that as soon as the baby’s born the soul’s going to go away, and it’s the first time she really experienced true love, so she was going through a lot emotionally.

I just didn’t think that she would have time to really think about how she looked. I don’t think it was a priority, and so for me as an actor it was important that I reveal that. Not get caught up in my own vanity as an actress, and portray the character as where she really was.”