The purpose of prenatal screening is obviously to identify genetic and other disorders before a child is born. In the majority of cases, the intention is that the pregnancy should be terminated if the child is found to be affected by a serious disorder. Despite this expectation, the law in Victoria does not recognize fetal abnormality as a ground for abortion. For an abortion to be lawful, the doctor must honestly believe, on reasonable grounds, that the abortion is 'necessary to preserve the woman from a serious danger to her life or her physical or mental health' and that the abortion is 'not out of proportion to the danger to be averted' (the Menhennitt rules). Although the danger to health has been extended to include danger on economic and social grounds, it is still necessary for a doctor to base the decision to abort on the risk to the mother's health, and not on the abnormal fetus. When the fetus is older, a doctor may be charged with child destruction as well as abortion. This requires proof that the doctor 'unlawfully cause[d] such child to die' and acted 'with intent to destroy the life of a child capable of being born alive'. These terms are open to interpretation but it is not necessarily a defence that the child had a serious abnormality.