Patient's question:
My friend is more than 4 months pregnant and had a high-risk result in the Down syndrome screening, so she went to the hospital for an amniocentesis. The result showed fetal chromosomal abnormalities. Why are the couple's chromosomes normal, but the embryo's chromosomes are abnormal?Doctor's answer:
The fetal chromosomes come from the sperm and eggs of both parents. If there are abnormalities in the sperm or egg chromosomes, the resulting embryo will also have abnormalities. Most of the abnormal sperm and eggs from the parents are randomly generated, with low reproducibility. However, some patients may have abnormal chromosome structures, such as balanced translocations or Robertsonian translocations, which can lead to abnormal gamete and embryo formation.Recommendation: It is recommended that both partners undergo karyotype analysis. If both partners have chromosomal abnormalities, it is advisable to try normal conception. If abnormalities are present, it is recommended to consider generational transmission.