This passage speaks of a case where men fighting negligently [due to their cations this is not considered an accident] caused a woman to have a miscarriage.
Despite the death of the baby, the punishment is a fine, rather than a punishment for killing.
They would be liable for additional damages if the woman was hurt. If the baby was born and lived but was hurt then the damages would be the usual ones for injuries.
I should add that the Jewish viewpoint on abortion is NOT at all similar to the Christian one.
Despite in being clearly forbidden (other than exceptions for health etc.) Jewish halacha does not consider it murder. An unborn child is considered as potential life, not as life, and while it is gravely forbidden to harm it, it is not murder.
As an example, if a pregnant women is tried in a capital case and sentenced to death, the sentence is carried out immediately (like all such sentences) and we do not wait for the child to be born first.