Early Pregnancy Spotting: Causes, Risks & What to Expect

Question
Dear Dr. Rappaport:
I am a 27-year-old mother of an 18 month old.  I am currently somewhere between 8 & 9 weeks pregnant.  My LMP was August 6th & I ovulated on August 23rd.  I thought I was having a period in early September but turned out to be pregnant a week later.  My progesterone was low so my doctor put me on prometrium, 400 mg daily.  The spotting stopped and my first ultrasound said I was 6 weeks and 1 day, which would have put my lmp at 8/14, and there was a strong and steady heartbeat.  I was diagnosed with a moderate sized Subchrionic Hemmorage in the upper right quadrant of my uterus.  The radiologist said not to worry about additional spotting.  I started spotting a few days after.  Had a follow-up transvaginal u/s which again showed a strong h.b. and a decrease in size of the SCH.  I have been spotting for a week now.  Mainly brown blood that is only on toilet paper.  I have not had cramping except for some light back pain, kind of a pinching.  I am really worried about the spotting.  How long should I expect it and should I be concerned?  Thank you.

Answer
It is common to have a subchorionic hematoma that develops within the folds of the developing placenta. It usually does not interfere with your pregnancy and resolves slowly over a few weeks time. The bleeding gets less and less and then stops. You do not have to curtail your activity or stay in bed. We usually do not use more than 200mg Prometrium per day, and you should stop the Prometrium after 12 weeks gestational age.   I don't know when you had your first sonogram, but the findings of the sonogram does not change the date of your last period. You still started your period on August 6, but you may have conceived later in the month. The SCH should dissipate before 14 weeks gestational age. Don't worry about it.