We live in a racist and classist society and we're all marinating in it 24/7. You aren't exempt; everyone has absorbed racist and classist beliefs just by existing.

Until that changes, it's what we do when we learn about the racism and classism inherent in an idea or a phrase that defines us. Now that OP is aware that it's racist and classist, they can choose not to use it anymore and can "spread the knowledge" to others.

This is absolutely, positively, 100% the correct answer to the question about crack cocaine specifically. The phrase "crack babies" is a racist, classist dogwhistle.

This is not to say that using cocaine in any form is safe during pregnancy! It can cause pregnancy complications, but a baby born addicted to crack is not one of them.

That said, most babies whose mothers used opiates during pregnancy (including methadone maintenance therapy) will experience opiod withdrawal symptoms after birth. This is called neonatal abstinence syndrome and is characterized by hypertonicity, irritability, vomiting/diarrhea, sneezing, poor sleep, poor feeding, and/or a distinctive high-pitched cry.