Question: how long does it take for a pregnancy test to show up negative after an abortion?
Answer: The disappearance of HCG from urine is exponential, with a half-life value of 1.3 days. A urine pregnancy test with a sensitivity of 1 IU/ml wil nearly always be negative in the course of 2 weeks after abortion. A positive test 4 weeks after abortion indicates an incomplete abortion or persistent trophoblast.