I apparently have an SCH

So, on 8/31 I woke up spotting and cramping very light pink and brown blood. I spotted for about an hour and then it stopped. I went for an emergency HCG blood draw and ultrasound. They heard baby’s heartbeat (148 bpm). And then told me I likely wasn’t miscarrying... then yesterday (9/05) they called and told me I have SCH about 1.6 cm.. they told me I don’t have any new limitations.. just to pay attention for any bleeding.. my sister had this condition 3 times and miscarried once from it. What can I do to help my odds? What was the size of your SCH? Is there anything I can do to prevent it from growing/bleeding?