What are the factors or causes of frequent miscarriage?

Patient's question:

Main symptoms: Frequent miscarriage
Onset time: Test results: Threatened miscarriage

Doctor's answer:

There are many factors or causes that can lead to embryonic death and spontaneous abortion, such as: genetic defects, systemic diseases, reproductive organ abnormalities, endocrine effects, bad habits, trauma and stimulation, immune function abnormalities, and environmental factors. It is recommended that both partners should go to the hospital for pre-pregnancy tests before planning to get pregnant again, to rule out unfavorable factors in the body and ensure safe conception, avoiding similar situations from happening again.