Thanks for your query at DoctorSpring. I would be happy to assist you with your query.
Normally, ITP is not associated with bleeding during pregnancy.
Unless the count is less than 20,000 there is no risk of spontaneous vaginal bleeding.
Also, during pregnancy, occasional brownish discharge is common, and might not be ominous.
In the light of your prior 3 miscarriages, and the pending report of the latest platelet count, I would ask you to consult your doctor for a check up and an ultrasound preferably, which would let you know regarding the baby's well being.
Right now you can schedule an appointment with your Obstetrician as soon as possible. If the bleeding persists, repeats itself, increases or is associated with cramping and pain, you should visit the ER right away.
Consulting your doctor immediately over the phone also is something I would recommend, as atleast you would come to know your latest labs, and thus be reassured.
With 3 prior miscarriages, you should not take any chances at all.
Meanwhile, take as much rest as you can.
Avoid stress, intercourse, jerky and long distance travelling or long working hours.
Take all the medication as prescribed to you. Wish you the best of luck.
Please feel free to ask any follow up questions that you might have.