If you think you might be pregnant again, take a test. If it shows up negative but you are still worried, see your OB. If it shows up positive, make an appointment ASAP because of your past history of miscarriage/stillbirths. If you do not know why you miscarried, you NEED to ask your OB. If he/she does not know, the best thing to do would be to ask for tests normally run on women who have multiple miscarriages/stillbirths.
If it turns out you are not yet pregnant, and you still do not have any clue as to why you miscarried/stillbirthed, ask your doctor or OB to help you find out why, be it tests or referrals to specialists that can help give you an answer, although, sadly, sometimes there is no answer.
I am so sorry for your loss. Losing a baby, born or not, is so tough, I know from experience.
