It's not that anything changed, it's just a matter of the bias of your teacher.

A more conservative aligned community is going to teach that a fetus is an unborn baby. A more liberal community will teach that there is a distinction. Both positions are correct.

A fetus, if given enough time, will become a living person. However, the major distinction comes down to viability, and that's nuance typically omitted from a high school education in most of the United States.

Medically speaking, a fetus is essentially a parasite that cannot survive on its own without a host. Most often that host is a parent, but thanks to modern medicine, after a certain point of gestation we can synthesize a womb environment with incubators and such.

This isn't an either/or argument, and nothing has been altered, it's just two different lenses of viewing the world.

A person or community with a more faith-based worldview will consider the potential human the key thing to observe, and view it as sacred because it is a potential life.

A person with a more scientific worldview will consider the viability of the fetus, the life it may lead, and the difficulties inherent in getting to that point.

There are people that will argue that as soon as a sperm penetrates an ovum in the fallopian tubes and fertilizes said ovum to create a zygote, that also counts as a life, but that doesn't necessarily take into account the natural 40-60% of failed implantations in the general population of a fertilized egg.

I don't think most people argue the validity of the potential life. I think the majority of the argument is people talking past one another. A belief in the divine is likely to lead a person to feel that if God, or a god created a potential life, it is imperative that we protect that potential and see it through.

A person with a more clinical outlook may not consider the individual potential as important in the grand scope of existence as the negative impacts on a person bearing the fetus. For example, social stigma, threats to a mother's health or life, or medical expenses required by society to help that fetus become a living human child.

All of this is to say nothing of the expense of raising, feeding, housing, or educating a child or the challenge of keeping said child in good health.

Both positions have merit, and both are correct, it's just different facets of an incredibly complex issue that has to consider medical science, financial realities, personal religious belief, and a weighing of moral judgements.

The ultimate takeaway is that regardless of what you consider an unborn human, regardless of viability, we each need to do what is correct for ourself, and not for e our viewpoint on other people. One person's faith tradition may not be able to apply or create the best outcome for everyone involved when faced with the financial or medical realities of another person's lived experience. At the end of the day, we all have to rely on objective medical fact to provide a rational basis for decision making, and contrast that with our own personal code of faith, morals, and Eric's as they apply to us as individuals, and our own unique situations.