Supporters of legal abortion spread falsehoods about the fetus because they cannot come to terms with the truth: a fetus is a human being.
They are utterly fixated on the foetus, which in their mind assumes all the attributes of personhood. They invest in a pre-human cluster of cells the same emotional passion nature intended for a child. The foetus IS their fetish.
As if mothers never do that. As if fathers, and other relatives do not do that.
Well, they'll argue that's their own fetus.
If they acknowledge the personhood of their own fetus, why not other fetuses?
Oh right, because that would deprive women of the convenience of getting rid of them by killing them.
If you do not acknowledge the humanity of the unborn child, you have to perform a lot of mental gymnastics to deal with the contradictions.
That's why supporters of legal abortion use a lot of euphemisms and half-truths like "cluster of cells".