Tables of Fetal Measurements: Crown Heel Length

The crown-to-heal length can be estimated from gestational age if there is normal development.

Sung and Singer: Liveborn

gestational age (weeks)	crown heel (cm), mean	crown heel (cm), low	crown heel (cm), high
20	25.6	23.4	27.8
21	26.7	25	28.4
22	27.8	26.2	29.4
23	28.9	25.9	31.9
24	30	28.3	31.7
25	31.1	29.1	33.1
26	32.2	29.8	34.6
27	33.4	29.9	36.9
28	34.5	32.2	36.8
29	35.6	31.2	40
30	36.7	32.5	40.9
31	37.8	34.7	40.9
32	38.9	33.2	44.6
33	40	36.5	43.5
34	41.1	37.1	45.1
35	42.3	39.4	45.2
36	43.4	37.5	49.3
37	44.5	37.5	51.5
38	45.6	40.5	50.7
39	46.7	42.3	51.1
40	47.8	43.6	52
41	48.9	43.5	54.3
42	50	46.2	53.8

week gestation with mean crown heel length =

= (0.8997036 * (crown heel length in cm))-3.012706

week gestation maximum for crown heel length =

= (0.7750055 * (crown heel length in cm))-1.129034

week gestation minimum for crown heel length =

= (1.0270155 * (crown heel length in cm))-4.074811

Sung and Singer: Stillborn

gestational age (weeks)	crown heel (cm), mean	crown heel (cm), low	crown heel (cm), high
20	24.9	22.6	27.2
21	26.2	22.6	29.8
22	27.4	24.9	29.9
23	28.7	25.4	32
24	29.9	25.6	34.2
25	31.1	24.6	37.6
26	32.4	27.1	37.7
27	33.6	30.4	36.8
28	34.9	29.3	40.5
29	36.1	30.2	42
30	37.3	33.7	40.9
31	38.6	35.9	41.3
32	39.8	34.4	45.2
33	41.1	38	44.2
34	42.3	38	46.6
35	43.5	37.7	49.3
36	44.8	37.6	52
37	46	38.1	53.9
38	47.3	43.4	51.2
39	48.5	43.6	53.4
40	49.7	46.5	52.9
41	51	46.6	56.4
42	52.2	49.2	55.2

week gestation with mean crown heel length =

= (0.8064293 * (crown heel length in cm)) - 0.110638

week gestation maximum for crown heel length =

= (0.7466038 * (crown heel length in cm)) - 1.142919

week gestation minimum for crown heel length =

= (0.8134105 * (crown heel length in cm)) + 3.2237983

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