Question
Why do couples with normal chromosomes have a fetus with chromosome abnormalities?
Answer
The chromosomes of the fetus come from the sperm and egg of both parents. If there are chromosomal abnormalities in the sperm or egg, the fetus may have chromosomal abnormalities. These abnormalities can occur randomly with a low recurrence rate, but some patients may have chromosomal structural abnormalities such as balanced translocation or Robertsonian translocation, leading to abnormal gametes and embryos. It is recommended that both partners undergo chromosomal karyotype analysis; if both partners have chromosomal abnormalities, it is suggested to try normal pregnancy; if one partner has an abnormality, genetic counseling and possible genetic testing are recommended.