Terapeutic abortion is a kind of abortion which is carried out because of medical necessity. In some cases, the pregnancy or childbirth is a medical risk to the health of the mother. In other cases, the unborn child would have grave birth defects. Therapeutic abortion is legal in most contries, even if other forms of avortion are illegal. Some countries also have a rule, that abortion is legal for the first part of the pregnancy and illegal afterwards. Even in these cases, therapeutic abortion is often legal. 