HCG Doubling Time Calculator

This tool turns two quantitative beta hCG results into a rate of change. Enter the first result, the second result and the number of hours between the two blood draws, and it returns the percentage change, the doubling time in hours and days, and what that rate works out to across a standard forty-eight hour interval. The expected rise is not one fixed number: it slows as the level climbs, so a doubling time that is normal early on would be unusual later. A single pair of readings does not confirm, rule out or explain anything, and only the clinician who ordered the tests can interpret them.