Blood in urine then passed sac 4 weeks later. Took hCG test 3 weeks later came back negative. Was it a miscarriage?

Miscarriage ? Passing tissue with a negative HCG (serum) test would suggest that you may have had a miscarriage if you had a positive HCG test initially. Miscarriages are very common especially for first pregnancies, mostly without most women knowing that they were pregnant.. About 30-40 percent of first pregnancies end in early miscarriage., and most subsequent pregnancies are normal.