It’s always bothered me when we talk about the ‘viability’ factor...when the whole abortion debate started in the 70’s viability was at 7-8 months now 40 years later it is 4 months or less and could get to 1 day in the next 40 years.
A healthy 30 year old man is viable for a couple of weeks confined to his home, unviable for a couple of weeks confined in a snowdrift. An astronaut in a space walk is viable in his spacesuit, unviable without it. An unborn baby is viable in the uterus of a healthy mom, but unviable if the uterus is cancerous; and so forth.
In fact, it would make much more sense if the viability argument were deployed in the opposite direction. It ought to be illegal to expel a baby from the womb if he or she is too young to live outside it; and at the point where the baby can live outside the uterus without risk to its health, the pregnancy can be gently terminated with a view to preserving both mother's and baby's well-being.
This acceptable termination of pregnancy ordinarily happens at around 40 weeks gestation, and is called childbirth.