How To Interpret Positive BHCG Levels After IVF: When Will You Know For Sure?

Question:

My question is about beta levels, and how to interpret what they indicate.This is my first IVF / first pregnancy, so this is a constant learning process.

1st Beta at 14 dpo (11 days past 3 day transfer) was 158.
2nd Beta at 18 dpo was 704.
3rd Beta at 21 dpo was only 1537.

My beta levels started off doubling, but then slowed considerably.I have an ultrasound upcoming next week, but not sure what to expect at this point. I am feeling very concerned about this change, and not sure if it still falls into normal range or is a valid cause for concern. Should I request a 4th beta? Can an ultrasound at 5 1/2 weeks provide a definitive answer to the viability of a pregnancy?

Thank you so much for your answer! C. from New York

Answer:

Hello C. from the U.S.,

Absolute values of the bHCG cannot be interpreted (although many people try to). bHCG's are evaluated based on their trend i.e. up/down and double every other day (actually it only needs to increase by 80%). I would caution you on trying to interpret how things are going by your bHCG levels unless they drop precipitously. The ultrasound will give you a better idea of how things are proceeding.

Viability cannot be established at 5-1/2 weeks. It is too early. That ultrasound is mainly to rule out an ectopic (tubal) pregnancy. Viability is established at 7-8 weeks gestational age.

You have a positive pregnancy test, which is a good thing! Now all you can do is wait and see how it progresses.

Good Luck,

Dr. Edward J. Ramirez, M.D., FACOG
Executive Medical Director
The Fertility and Gynecology Center
Monterey Bay IVF Program
www.montereybayivf.com
Monterey, California, U.S.A.