Chromosome 7 is an autosomal chromosome, and the consequences of having an excess of chromosome 7 include miscarriage during pregnancy, preterm labor, and abnormal mental development after birth. 1. Miscarriage during pregnancy: Normally there will be two chromosome 7s. However, an excess of chromosome 7 is a chromosomal developmental abnormality, which may lead to spontaneous abortion during pregnancy. 2. Preterm labor: Because the embryo may have abnormalities during development, the possibility of preterm labor cannot be ruled out. 3. Abnormal intellectual development after birth: chromosome 7 has a certain relationship with intelligence, so the possibility that the child will be born with intellectual deficiencies and other problems cannot be ruled out. If the chromosome 7 is too much, you need to do genetic testing and other further examination. If there is a clear problem, the pregnancy should be terminated under the guidance of a doctor.