With the progress of society and the development of medical research, people are gradually paying more attention to infertility and pregnancy failure, especially when repeated pregnancy failures (two or more consecutive spontaneous abortions occurring in the early and middle stages of pregnancy, fetal abortion), of which the male factor is receiving more and more attention, so what are the direct or indirect causes of pregnancy failure? 1, abnormal oxidative stress reaction Excessive oxidative stress produces a large number of oxidative stress products damage DNA, resulting in abnormal embryo development and pregnancy failure. The use of antioxidants can help reduce DNA damage, such as carotenoids, VITC, E and zinc. 2, karyotype abnormalities The number of chromosomes (kernicterus, trisomy, etc.), structural abnormalities (translocation, inversion, marker chromosomes, etc.) and polymorphisms (large Y, small Y), and factors that cause chromosomal abnormalities, including antineoplastic drugs, organophosphorus, ionizing radiation, rubella, cytomegalovirus, etc., may lead to chromosomal abnormalities and thus pregnancy failure. The risk of miscarriage is particularly high when both men and women are older than 35 years old and men are older than 40 years old. 4, Y chromosome abnormalities such as complete AZFC deletion patients have a large number of sperm with sex chromosome deletion, there is a high rate of spontaneous abortion and may be out of both sexes abnormalities. 5, sperm DNA damage Causes include varicocele, chemotherapy or radiotherapy, smoking, leukocyte spermia, ichthyosperm deficiency, etc., damage to sperm DNA and then early pregnancy failure may occur. In summary, these are the main factors of male pregnancy failure, if repeated pregnancy failure should pay attention to the factors of male partner and actively search for the cause. The examination items for male partner with abnormal embryonic development: semen routine, karyotype + Y chromosome microdeletion, urinary and genital ultrasound, sperm DNA integrity test, etc.