This reply assumes you are in NSW.
If you are not in NSW, then the law may be different where you are.
In NSW, a fetus has no legal personality of its own.
So, as a matter of law, there is no "unborn baby".
Which means that, legally speaking, there is nothing
at risk from her behaviour apart from herself.
When the baby is born, then it is a legal person in its own right.
The authorities and the courts can concern themselves with it once it's born.
Until then, perhaps it would be helpful to start collecting information (however informal)
that might at some future point become evidence in a care and protection proceeding
once the child is born.