IVF

[JES24]

Do you remember the name of the hormone they were testing for?

[Ghost]

should I worry?

You should not worry. Stress hurts your chances.

However, regarding your serum hCG values, it's hard to tell from the information you've given. By "implantation" you probably mean transfer. Transfer of what? Day 2, Day 3, Day 5 blasts? It makes a difference in this.

Six days after transfer your hCG was still 40? And three days after that it had fallen to 20? Just a guess, but sounds like maybe a day 2 transfer??? Nine days after a day 2, I would expect hCG to not yet be rising, or just barely beginning to rise (could easily be less than 20). Nine days after day 5 blastocysts, you should have rising hCG (more than 20).