Are you trying to collect peoples' opinions on this question? I am assuming that this is a baby that is being put up for adoption. In this situation, I think it is important to make sure the baby has immediate medical attention. Then, I would alert the proper authorities about the abuse. If it is Social Services, I would be diligent to make sure that the situation was investigated properly. I have learned the hard way, as a teacher, that one cannot assume that such things are taken care of properly after one alerts Social Services. They have a huge case load and it does not hurt to check and check and check on their progress. It is important to make sure that if the abuser is a foster parent that the baby be immediately removed from that placement and put somewhere else.
Would the abuse have any effect on whether or not I would adopt her? For me, no. I would make sure that the baby was monitored as she grew up, though, and watch for signs that she might need further counseling. You don't give an age, but no matter, there can always be long-term consequences even if the abuse happens when she is an infant.
I personally know of a situation where potential adoptive parents pulled out of an adoption when they discovered, after the birth, that the baby might have some developmental issues, so others may feel differently about this. My view is that such a baby would maybe need an extra degree of love, but adopting the baby into a home that was not prepared to deal with potential issues might make things even worse for the poor little girl.