"...would you rather have a written Constitution of the United States of America? Or would you rather have a Congress that had not written document but could govern merely by majority rule? Or a president who could govern by consensus of counselors?..."
Depends, now doesn't it? If I were still a fetus, I would rather be governed by a majority in Congress. My chances of making it out alive would be better. Only the Constitution demands abortion; anytime, anywhere, for whatever reason.
So you actually think abortion appears in the pages of the Constitution? I never read about it there.