Table 1.

Amplification of Fetal Y-Chromosomal Sequences of Single Cells Isolated from Maternal Blood

Mothers	Microdissected cells	Y-positive cells	Mononucleated cells (Y-positive)*	Polynucleated cells (Y-positive)*
Male fetuses
1	2	2	1 (1)	1 (1)
2	3	2	3 (2)	0
3	8	7	6 (5)	2 (2)
4	2	1	2 (1)	0
5	3	1	3 (1)	0
6	5	2	5 (2)	0
Total	23	15	20 (12)	3 (3)
Female fetuses
7	6	0	6	0
8	3	0	1	2
9	3	0	2	1
10	2	0	1	1
11	6	0	5	1
12	3	0	3	0
13	3	0	2	1
Total	26	0	20	6

*The number of Y-positive cells is indicated in parentheses.