Stop Mothers from intentionally causing harm/death to their unborn child by abusing Illegal/Prescription Drugs.

My daughter has been an addict for 3 years. She has been pregnant as many times, not one of these pregnancies has made it past the first term. I was unaware that during the first two pregnancies that her and her boyfriend were addicts. Now knowing how much herion they were using, I believe the drug use is the reason she miscarried. Just recently we found out she was pregnant a third time. When I found out that she was using herion again, I thought that I could turn to the authorities for help to protect my grandchild. I was wrong. I don't understand how a woman can know she is pregnant and intentionally cause harm/death to her unborn child by abusing illegal/prescription drugs and I can't press charges against her for doing so. If I intentionally caused harm/death to another person they could prosecute. If someone is pregnant and they are killed do you not get charged for both deaths? But I have to wait until the child is born to take action. If only I was so lucky to see my grandchildern make it to birth. I have celebrated and morned THREE (3) Grandchildren. Please help me to get a Law passed that will allow a concerned parent, boyfriend, husband, friend to be able to turn to the authorities for help. To be able to press charges for intentionally causing harm/death to their unborn child.