Pennsylvania Paternity FAQ's

1) When can a party assert paternity questions?
One of the strongest presumptions in the law is that a married woman's child a child of her marriage. A husband of such a woman can only prove that he is not the father by proving that he had no access to his wife during the time of conception or that he was sterile. His evidence must be very strong and "clear and convincing".

The raising of paternity questions is support defense. However, the defense can be waived by openly admitting paternity and supporting the child.