This is just an oportunistic political move ahead of next year's elections. The government doesn't really care about abortion. Source: Argentinian living in Argentina.
(While not quite applicable here,) the easiest example to explain this is when the pregnancy threatens the lives of both mother-to-be and unborn child. An abortion will end the life of the child but the mother gets to live. In the other case both mother and child would die. So an abortion would be "net positive" because only the child dies and not both of them.
No one who advocates for life believes that there aren't any mitigating circumstances.
People who advocate for life believe that there aren't any mitigating circumstances that justify murder.