Table 2:

Median, 5th, and 95th percentiles for AP measurements

Gestational Age (wk)	Imaging Modality
	US 2D			US 3D			MRI
	%5	Median	%95	%5	Median	%95	%5	Median	%95
21	7.08	7.79	8.71	5.70	8.10	10.30
22	7.51	9.51	10.62	7.40	9.15	12.40
23	7.27	8.72	10.25	6.30	8.80	11.00
24	8.96	9.49	10.64	8.60	9.85	11.00
25	9.58	10.73	13.17	9.90	10.50	14.60
26	8.76	11.28	14.17	8.10	11.30	12.80
27	10.06	11.44	12.69	9.30	12.50	14.80	9.11	9.33	11.10
28	10.75	12.32	14.94	9.20	12.30	15.90	8.90	9.97	12.04
29	10.09	12.61	15.01	11.20	12.80	14.40	8.93	11.05	13.28
30	11.06	13.36	14.94	10.70	13.70	16.80	10.39	11.92	15.01
31	12.69	14.01	15.81	11.80	14.60	18.00	11.07	12.30	13.96
32	11.93	13.87	17.38	10.70	15.20	18.40	11.40	13.04	13.90
33	12.63	15.11	17.83	11.80	13.05	19.70	11.91	13.26	15.22
34	12.36	15.94	17.82	12.00	15.60	21.40	11.18	13.77	15.10
35	13.84	16.40	17.40	12.60	15.75	18.90	12.70	14.83	17.17

Note:—%5 indicates 5th percentile; %95, 95th percentile.