Biparietal Diameter (BPD)

Hadlock FP, Deter RL, Harrist RB and Park SK.

Estimating fetal age: computer assisted analysis of

multiple fetal growth parameters.

Radiology 1984;152:497-501

GA (wks)	-2SD	Mean	+2SD
12	11	17	23
13	15	21	27
14	19	25	31
15	23	29	35
16	26	32	38
17	30	36	42
18	33	39	45
19	37	43	49
20	40	46	52
21	44	50	56
22	47	53	59
23	50	56	62
24	53	59	65
25	56	62	68
26	59	65	71
27	62	68	74
28	65	71	77
29	67	73	79
30	70	76	82
31	72	78	84
32	75	81	87
33	77	83	89
34	79	85	91
35	81	87	93
36	83	89	95
37	84	90	96
38	86	92	98
39	87	93	99
40	88	94	100