I Have Had 2 Miscarriages In The Past 6 Months.

I have had 2 miscarriages in the past 6 months. I am currently 6 weeks pregnant and have a subchorionic hematoma, about the same size as the gestational sac, located directly next to it. I am experiencing constant lower back pain in the lower left quadrant, but no bleeding at all. I am considered high risk, due to my previous preterm labors. My first miscarriage was due to chromosomal abnormalities at 8w6d, and my second was not tested, although there was also a subchorionic hematoma above the gestational sac (MC was @6 weeks pregnant). Would should I do to better my chances of this being a viable pregnancy?