Persistence of male hematopoietic CD34+ cells in the circulation of women does not affect prenatal diagnostic techniques.

Objective: We aimed to verify whether fetal microchimerism, because of persisting fetal hematopoietic CD34(+) cells from previous pregnancies, could interfere with the development of genetic tests based on using these cells, isolated from maternal blood for the diagnosis of fetal aneuploidies.

Study Design: CD34(+) cells, isolated from blood of parous women with at least 1 son and nulliparous women, were analyzed by using qualitative polymerase chain reaction (PCR), quantitative PCR, and fluorescence in situ hybridization (FISH) to establish whether these molecular techniques are concurrently capable of detecting circulating male DNA.

Results: By qualitative PCR, male DNA was found both in parous and nulliparous women, whereas by quantitative PCR and FISH analyses, no male DNA or male nuclei were revealed except in 1 cultured CD34(+) sample from a nulliparous woman.

Conclusion: Fetal hematopoietic CD34(+) cells can be used in the noninvasive prenatal testing of fetal aneuploidies because the presence of fetal microchimerism does not affect fetal diagnosis in current pregnancies.