Tibia Length

Chervenak FA, Isaacson GC, Campbell S (eds)

Ultrasound in Obstetrics and Gynecology 1992;

Table A1-12:pg 1783.

Boston: Little, Brown and Company

GA (wks)	-2SD	Mean	+2SD
12	5.6	8.4	11.2
13	5.9	9.7	13.5
14	9	12.8	16.6
15	11.4	15.2	19
16	13.7	18.5	23.3
17	16.7	21.5	26.3
18	18.4	24.2	30
19	22.2	27	31.8
20	25.3	29.7	34.1
21	27.9	31.9	35.9
22	29	34.6	40.2
23	32.7	37.1	41.5
24	33.4	40	46.6
25	38.1	41.3	44.5
26	39.4	43.4	47.4
27	41	46.8	52.6
28	43.3	47.7	52.1
29	45.9	50.5	55.1
30	45.2	51.2	57.2
31	48.2	54	59.8
32	51	54.2	57.4
33	48.5	55.9	63.3
34	53.2	57.6	62
35	55.7	60.7	65.7
36	54.7	60.9	67.1
37	60	64.4	68.8
38	57.3	63.1	68.9
39	57.8	64.6	71.4
40	59.1	66.1	73.1
41	59.2	66.2	73.2
42	61.4	67.6	73.8