Follow-up of multiple aneuploidies and single monosomies detected by noninvasive prenatal testing: implications for management and counseling.

Noninvasive prenatal test results of autosomal monosomy or multiple aneuploidies are rare but have a diversity of underlying biologic causes. Some reflect the fetal karyotype; some reflect the presence of other maternal or fetal chromosome abnormalities, and a small number are linked to maternal disease.