Definition: Spontaneous abortion in 3 or more times is called. Main causes: 1, genetic and chromosomal abnormalities Either or both men and women may have; 2, infection Either or both men and women, such as mycoplasma, chlamydia, viruses and other infections; 3, immune factors Such as anti-sperm antibodies (AsAb), anti-endometrial antibodies, etc.; 4, luteal insufficiency; 5, uterine abnormalities such as unicornuate uterus, relaxed cervix, uterine fibroids, etc.; 6, systemic factors Malnutrition, hypothyroidism, diabetes, etc.; 7, environmental and occupational factors such as radiation, radiation, drugs, etc. Once there is an unexplained spontaneous abortion, do not delay, and do not wait, should go to the regular hospital for standardized examination and treatment as soon as possible.