Again, forget the legal definition of murder
We’ll go with your definition, killing a baby
If you say both lives are equal to one another, and both parties are innocent (unlike your fantasy with the drug dealer having sex with a scientists wife…) how can you morally justify killing one to maybe save the other?
I wonder if you would have the same moral consistency after the baby is born? If there was a situation where only one of their lives could be saved, would you still choose to save the mothers life?