why does my doctor suggests prometrium

Deepu

I am 5w 4 d. Its my first pregnancy.I got my blood tests yesterday and now My OB calls and tell me all blood works looks good but she suggests me to take prometrium daily 2 times. Previously i had misscarriage in last January. I dont know what’s happening again.. I just want this baby to stick to me. I am really freaking out. If anyone knows about this please help me..