When someone miscarries, they cry because they have an unfulfilled emotional attachment to the idea of having a baby, not because they think the rights of the embryo have been violated or that the embryo has suffered in any way.
Just the "idea of having a baby"? Right. Posit that to any woman who has miscarried, and see for yourself the veracity of that nice little theory. Posit that to the woman (have you every known any?) who has held in her hand the miscarried fetus, watching him die and sobbing intensely. Ask her what she did with the "tissue," with the "potential human," with the "idea of having a baby." Ask her if she flushed it, like a fish, down the toilet or if she buried it. Ask her if she discarded it, like a tampon, in the garbage. Ask her if she sobbed similarly for a tampon, reflecting the failed attempt to have a baby. Cute theory, but fundamentally disconnected with reality, and heartless.