Due to many factors such as pollution, radiation, body mass, diet, stress and infection, the rate of fetal abortion and recurrent miscarriage remains high, and we often attribute the problem to the female partner when looking for and treating it. However, did you know that the male partner as the other half of the fertility also has ten factors that endanger the development of the embryo? 1. Chromosomes Chromosomal abnormalities are probably the most common factors for fetal abortion and recurrent miscarriage, except that doctors and patients do not pay enough attention to embryonic or fetal chromosomal examinations, most of which are aimed at the parents. Enhancing the chromosomal examination of embryos for abortion will help us find more unknown causes. 1) Embryo chromosome examination: chromosome examination should always be performed on embryos with confirmed fetal abortion. Examination of early gestational tissues at less than 6 to 8 weeks of gestational age (uncomplicated menstruation to confirmed embryonic abortion) reveals a chromosomal abnormality rate of about 60%. The abnormalities may be due to parental chromosomal causes or to problems in the development of the embryo itself. 2) Parental chromosome examination: Parental chromosomal abnormalities cause embryonic arrest in about 4.85 to 10.8% of cases, the most common being chromosomal ectopic or inversions. If the parents are known to have genetic factors, the chances of having an empty gestation sac may be higher. 2. Poor semen quality Increased leukocytes in semen (>1×106/ml), oligospermia (<20×106/ml), polyspermia (>250×106/ml), teratozoospermia (abnormal sperm rate >85%), and sperm cell nuclear and chromatin concentration can lead to fetal abortion and recurrent miscarriage. 3, increased rate of sperm DNA fragmentation A large number of studies have proven that sperm nuclear DNA breakage or fragmentation has adverse effects on pregnancy. DNA damage has become a major obstacle to successful pregnancy with normal sperm morphology. Sperm DNA fragmentation rates of >30% predispose to fetal abortion and recurrent miscarriage. An increase in sperm DNA fragmentation rate will also increase the rate of embryo loss after IVF significantly. 4. Anti-sperm antibodies The male partner’s own anti-sperm antibodies due to reproductive tract infection, injury, surgery, etc. will not only affect sperm production, sperm movement, sperm crossing the cervical mucus and zona pellucida, but also affect fertilized egg implantation and embryo development leading to miscarriage. If the mother’s blood type is A, B or AB, there is a 75% chance that the fetus will not be of type O. These embryos with different blood types from the mother will not be able to “follow the customs” and the red blood cell A or B or AB antigens will cause the mother to produce antibodies. The antibodies enter the fetal blood circulation and cause fetal sterilization. By the same token, if one of the parents is RH positive and the other is RH negative, there will also be blood group incompatibility. 6. Thrombophilic mutations Polymorphisms in genes are associated with recurrent miscarriages of unknown origin, with either spouse carrying a thrombophilic mutation strongly associated with recurrent miscarriages, and with a higher correlation for those with more than 5 miscarriages than those with 2-3 miscarriages (37% and 26%, respectively). Researchers have pointed out that the miscarriage rate of husbands carrying more than one thrombophilic mutation is higher than that of wives carrying more than one thrombophilic mutation. 7, infection factors mycoplasma, chlamydia, syphilis spirochete, eugenics four or TORCH syndrome (herpes simplex virus, rubella virus, cytomegalovirus, toxoplasma), gonococcus, hepatitis B virus and other infections, will not only affect the male reproductive tract, sperm quality and affect fertility, but also infect the female, affecting embryonic development, resulting in embryonic chromosomal aberrations and lead to fetal abortion. The impact of tobacco and alcohol on embryonic development has been confirmed, although many scholars believe that female tobacco and alcohol addiction has a greater impact on the embryo, but we can not ignore the fact that male tobacco and alcohol addicts are larger groups, longer, and will have a greater impact on sperm quality. 9, environmental impact Air pollution, radiation, high temperature, decoration, paint, pesticides, formaldehyde, phthalates, heavy metals, sulfur dioxide, pets, etc. are likely to cause a decrease in sperm quality and increase the rate of deformities and affect fertility. 10, the impact of drugs Many clinical drugs such as anti-tumor, anti-hypertensive, anti-androgen, anti-depressant, anti-anxiety, treatment of insomnia and other drugs can have an impact on semen quality, and must be used under the guidance of a professional doctor during the preparation for pregnancy. Avoiding the above factors is the only way to improve sperm quality, reduce the occurrence of fetal abortion and recurrent miscarriage, and to have a healthy, smart and beautiful baby.