Thanks for the query.
Little bit of spotting can be seen during early pregnancy
due to different causes like:
Burring of the gestational sac
into the uterine wall
Increased blood supply to the local genital organsHormonal
But as you are having previous history of miscarriages better to get examined and take progesterone
supplementation with your doctor's advice.
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429