Understanding HCG Levels and Fetal Development: A Medical Case

Question
Good Morning,

I took my first blood test on 10/08/08 and my hcg levels were at 37624 by 10/13/08 they had dropped to 33586 they did an u/s at the hospital and it showed a sag but no fetal pole on 10/17 i went back to the ER and my hcg had dropped again to 32694 and the u/s still showed the sag plus the yolk but still no fetal pole i went in to my obgyn yesterday and they did a blood test they hcg level is at 26825 but the u/s now shows a fetal pole measuring 3 mm. The doctors say i more than likely will have a miscarriage since my hcg levels are dropping. I am so confused and worried any insight?

Answer
Hi Carolina
           I can understand why you'd feel confused!
Unfortunately a declining hcG level usually means that the pregnancy is failing as hcG is what develops the embryo & placenta. The discovery of a fetal pole could be because it wasn't picked up before, which does happen depending on the position of everything when you were scanned.
You don't say how many weeks pregnant you are but a foetal pole is visible at 6wks, maybe accompanied by a heartbeat. By 7/8wks the heartbeat should definately be visible.
It's not really known why pregnancies fail. It's said that it's possibly caused by chromosomal abnormalities which happens during conception, resulting in the embryo not developing properly & never having a chance of surviving.

I hope this has helped & you feel a little more informed. If you have any more questions then plesase don't hesitate to contant me.

Kindest Regards
Sarah