Understanding Unexpected Positive Pregnancy Tests After Abortion

Question
Hello Dr. Joan,
On Dec. 8, 2007 I had an abortion. I had unprotected sex on Dec. 28 2008 I took two pregnacy tests after that and they both came out negative but when I return for my follow up my uterus was clean but the urine test came out positive...I took a home pregnancy test on the day I went to the follow up and it also came out negative. Could it be that I'm pregnant or is it still the hormones in my body? Can a blood test shows that I have a miscarriage or an abortion?

Answer
Dear Sharm,
It could be that you are pregnant again, or it could still be hormones in your body.  You can know the answer by taking two blood tests, at least 48 hours apart.  If the hormone level is going up, it is a new pregnancy.  If they stay the same or go down it is from your original pregnancy.  You can also just check another urine pregnancy test in a week.
I hope this is helpful,
Doctor Joan