| |
HC
|
AC
|
FL
|
|---|
|
z-score
|
Pregnancy duration (days)
|
95% CI
|
Pregnancy duration (days)
|
95% CI
|
Pregnancy duration (days)
|
95% CI
|
|---|
| |
Unadjusted results
|
|---|
|
-2.5
|
289.6
|
288.0, 291.1
|
289.0
|
287.4, 290.6
|
288.3
|
286.6, 289.9
|
|
-2.0
|
288.5
|
287.1, 289.8
|
288.0
|
286.6, 289.4
|
287.4
|
286.0, 288.8
|
|
-1.5
|
287.3
|
286.2, 288.4
|
287.0
|
285.8, 288.1
|
286.5
|
285.3, 287.6
|
|
-1.0
|
286.1
|
285.2, 287.0
|
285.9
|
284.9, 286.8
|
285.6
|
284.6, 286.5
|
|
-0.5
|
284.9
|
284.1, 285.6
|
284.7
|
284.0, 285.5
|
284.6
|
283.8, 285.3
|
|
0.0
|
283.6
|
282.8, 284.2
|
283.5
|
282.8, 284.2
|
283.6
|
282.8, 284.3
|
|
0.5
|
282.2
|
281.4, 283.0
|
282.3
|
281.5, 283.1
|
282.5
|
281.7, 283.3
|
|
1.0
|
280.8
|
279.7, 281.8
|
281.1
|
280.0, 282.1
|
281.4
|
280.3, 282.5
|
|
1.5
|
279.3
|
277.8, 280.7
|
279.7
|
278.3, 281.1
|
280.3
|
278.9, 281.7
|
|
2.0
|
277.7
|
275.8, 279.5
|
278.3
|
276.4, 280.1
|
279.1
|
277.3, 280.9
|
|
2.5
|
276.1
|
273.6, 278.4
|
276.9
|
274.4, 279.2
|
277.9
|
275.6, 280.1
|
|
P-value†
|
<0.0001
| |
<0.0001
| |
<0.0001
| |
| |
Adjusted for the difference between LMP- and HC-based gestational ages.
|
|
-2.5
|
286.9
|
282.9, 290.4
|
286.6
|
284.5, 288.6
|
286.0
|
284.1, 287.8
|
|
-2.0
|
286.3
|
283.0, 289.2
|
286.0
|
284.2, 287.7
|
285.5
|
283.9, 287.1
|
|
-1.5
|
285.6
|
283.1, 287.9
|
285.4
|
284.0, 286.8
|
285.1
|
283.8, 286.3
|
|
-1.0
|
284.9
|
283.2, 286.6
|
284.8
|
283.7, 285.8
|
284.6
|
283.5, 285.5
|
|
-0.5
|
284.2
|
283.2, 285.3
|
284.2
|
283.4, 285.0
|
284.1
|
283.3, 284.8
|
|
0.0
|
283.5
|
282.8, 284.2
|
283.5
|
282.8, 284.2
|
283.5
|
282.8, 284.2
|
|
0.5
|
282.8
|
281.7, 283.9
|
282.9
|
282.0, 283.7
|
283.0
|
282.2, 283.8
|
|
1.0
|
282.1
|
280.2, 283.9
|
282.2
|
281.1, 283.4
|
282.5
|
281.4, 283.5
|
|
1.5
|
281.3
|
278.5, 284.0
|
281.6
|
280.0, 283.1
|
282.0
|
280.5, 283.3
|
|
2.0
|
280.6
|
276.6, 284.0
|
280.9
|
278.8, 282.8
|
281.4
|
279.6, 283.2
|
|
2.5
|
279.8
|
274.7, 284.1
|
280.2
|
277.5, 282.6
|
280.9
|
278.6, 283.0
|
|
P-value†
|
0.089
| |
0.004
| |
0.008
| |
- Pregnancy duration calculated from a certain and regular last menstrual period (LMP) in 541 pregnancies with spontaneous onset of labour are presented according to fetal size at 10–24 weeks of gestation, i.e. according to z-scores* of head circumference (HC), abdominal circumference (AC), and femur length (FL) in multivariable linear regression** (upper panel). Values for pregnancy duration when adjusted for the difference between LMP- and HC-based gestational ages are shown in the lower panel.
- * Z-scores according to gestational age specific means and standard deviations of each biometric measure.
- ** To normalize the data pregnancy duration used in the regression model are transformed to the power of 10.
- † Test for the association between z-score of each biometric measure and pregnancy duration.
