A morphologic study of trophoblast isolated from peripheral blood of pregnant women.

Objective: Our purpose was to evaluate the morphologic characteristics of cells separated from peripheral maternal blood with immunomagnetic beads coated with trophoblast-reactive monoclonal antibodies of restricted specificity.
Study Design: Blood samples were collected from 14 pregnant women at 9 to 12 or 16 to 18 weeks' gestation. Immunomagnetic beads coated with trophoblast-reactive monoclonal antibodies were used to isolate cells from the blood. The isolated cells were then fixed, embedded, and sectioned to enable morphologic identification.
Results: Multinucleate cells identical to syncytiotrophoblast sprouts were identified in 12 of 14 samples.
Conclusion: Multinucleate syncytiotrophoblast can be isolated from the peripheral blood of normal pregnant women in both the first and second trimesters of pregnancy. The isolated trophoblast may allow prenatal genetic diagnosis by a noninvasive technique.