- Genetic defects Spouse with chromosomal abnormalities can transmit to the fetus, and then cause abortion. There are about 50~60% fetus with chromosomal abnormalities will undergo spontaneous abortion. The chromosomal abnormalities can include:
- Aneuploidy: Aneuploidy refers to an abnormal number of chromosomes, and is a type of chromosome abnormality, such as three-body, x single and Triploid.
- Chromosome structural abnormalities: the chromosome structural abnormalities mostly refer to the breakdown of chromosome arm, inverted, deletions and translocations.
A small number of embryos with chromosomal abnormalities in term time, will happen deformities or functional defect after birth.
- Maternal factors
- Systemic diseases: Pregnant women suffering from infection, high fever, severe anemia, heart failure, chronic nephritis, and hypertension.
- Genital abnormalities: Uterine malformation (Uterine dysplasia, double uterine, uterine septum), Uterine cancer such as sub mucosal fibroids, Severe cervical trauma and relaxation of the cervix
- Endocrine abnormalities: Hypothyroidism, Severe diabetes, Luteal phase defect
- Bad habits: Smoking, alcohol, drug such as heroin
- Trauma and stimulus: Serves shock and uterine trauma, Overstrain, anxiety, fear and sad
- Immune dysfunction The immune factors for the spontaneous abortion may include:
- Paternal histocompatibility antigens
- Fetus antigens
- Blood group antigens (ABO and Rh)
- The lack of maternal blocking antibodies during pregnancy
- Anti-sperm antibodies
- ……
- Environmental factors Pregnant woman excessively expose to chemical substances such as arsenic, lead, formaldehyde, benzene, chloroprene, ethylene oxide and so on.