Telling Your Family

I told my husband last week that we are expecting. I kept the secret for 10 days before telling him. I had my first ultrasound this past Wednesday. I am going to have another this coming Wednesday (I will be 7w5d). Thinking I am going to need to tell my mom and MIL. I know by telling my MIL, I will need to tell more people than I had anticipated, at least the siblings on both sides and pray she can keep her mouth shut and not tell aunts and uncles. I have already had two miscarriages, and don't want extended family knowing until after first trimester. Any ideas on how to say this nicely without offending?

Already know how I am telling my mom.... just don't know how to tell his family.....