No, but still risk
Miscarriages are most commonly (about 70-75%) caused by an abnormal number of chromosomes in the pregnancy
Downs (3 chromosome 21s) is one of the most common chromosomes to be abnormal. Still, the risk of a live-born child with downs is about 1 in 217 (age 37) and 1 in 166 (age 38). If you have multiple miscarriages then see a specialist to discuss testing. Best wishes.