The fixation goes back 1000s of years. Anyone who has read books on ancient China surely has read how court servants would monitor, measure, and do god knows what else with royal excretions of all sorts.
There is no way in hell I would take the test. Once you get the ARC for marriage, that is the end of the bloody tests in my eyes. I make sure I have good medical coverage in addition to the socialized insurance, but (except for utilizing the NHI for colds and Chinese medicine), I want to deal with the doctors here as little as possible. They just don’t like people (foreigners even less) to question their judgement. I order all my prescriptions online from overseas. Only a little more expensive, and I can get a years supply rather than a month or two.
You definitely don’t have to take the test–unless you enjoy these sort of things. I sure to hell wouldn’t.