Table 2.

Mean TREC and KREC levels at different gestational ages

Gestational age (weeks)	Infants (n)	Mean TREC level (copies/3.2 mm blood spot)	Mean KREC level (copies/3.2 mm blood spot)
20	1	262	139
21	2	97	180
22	3	84	97
23	23	53	52
24	31	68	58
25	38	64	70
26	50	71	62
27	58	89	65
28	53	93	76
29	97	114	91
30	97	139	110
31	122	134	99
32	199	146	90
33	283	139	87
34	390	142	93
35	663	153	97
36	1347	156	103
Total	3457