Understanding Blood on an Ultrasound After Miscarriage

Question
I have a 16 month old daughter, and had a miscarriage in December at 9 weeks.  I had an appointment on Tuesday (7 weeks 3 days), it showed the baby and the heart beating, but it also showed some blood.  I have not had any spotting or bleeding, the doctor put me on Prometrium.  Why would blood show up on the ultrasound?  What could the cause be?  The doctor didn't seem to act like it was a big deal.  Thank you

Answer
Mary,

Sometimes, for whatever reason, blood shows up in early pregnancy behind the uterus.  Your doctor did the right thing by putting you on progesterone (low levels of progesterone may cause a miscarriage).  Most of the time, the blood resolves itself and the pregnancy is carried to term just fine.  Make sure your doctor does a follow up ultrasound to see if the problem has gone a way.  If you experience any spotting, call you doctor right away.  Good luck!