Crown –Rump Length (CRL)

Hansemann M et.al.

Geburtsh Frauenheilk 1979;39:656-666

GA (wks)	-2SD	Mean	+2SD
7+1	2.3	6.9	11.5
7+2	2.8	7.6	12.5
7+3	3.2	8.3	13.4
7+4	3.6	9	14.3
7+5	3.9	9.6	15.2
7+6	4.3	10.2	16.1
7+7	4.7	10.8	16.9
8+1	5	11.4	17.8
8+2	5.4	12.1	18.7
8+3	5.8	12.7	19.6
8+4	6.2	13.3	20.5
8+5	6.6	14	21.4
8+6	7	14.7	22.4
8+7	7.5	15.4	23.4
9+1	8	16.2	24.4
9+3	9.1	17.8	26.5
9+5	10.3	19.6	28.8
9+7	11.7	21.5	31.2
10+2	13.3	23.6	33.9
10+4	15.1	25.9	36.6
10+6	17	28.3	39.6
11+2	20.3	32.4	44.4
11+4	22.7	35.3	47.9
11+6	25.2	38.3	51.4
12+2	29.3	43.2	57.1
12+4	32.2	46.6	61.3
12+6	35.3	50.2	65.1
13+2	40	55.6	71.3
13+4	43.2	59.4	75.5
13+6	46.4	63.1	79.8
14+2	51.3	68.8	86.3
14+4	55.6	72.6	90.6
14+6	57.8	76.3	94.8
15+2	62.5	81.8	101.1
15+4	65.6	85.4	105.2
15+6	68.6	88.9	109.2
16+2	72.8	93.9	115
16+4	75.5	97.1	118.7
16+6	78	100.1	122.2
17+2	81.5	104.4	127.3
17+4	83.6	107	130.4
17+6	85.6	109.5	133.4
18+2	88.3	113	137.7
18+4	89.9	115.1	140.4
18+6	91.5	117.2	142.9
19+2	93.5	120	146.5
19+4	94.8	121.9	148.9
19+6	96.2	123.7	151.2
20+1	97.5	125.5	153.6
20+3	98.9	127.4	156
20+5	100.3	129.4	158.5
20+7	102	131.6	161.2
21+1	102.9	132.8	162.6
21+2	104	134	164.1