Table 4

Mean differences in length of pregnancy by maternal height1 restricted to pregnancies with spontaneous onset of delivery2
Difference in pregnancy length (days)
Crude estimate3 Adjusted for obstetric and socioeconomic factors4 Additional adjustment for maternal cardiovascular risk factors5
Maternal height (in quintiles) N Mean difference Mean difference 95% CI p for trend Mean difference 95% CI p for trend
Estimated date of delivery based on US
 <163 687 0 0 Ref 0 Ref
 163-165 593 0.5 0.5 −0.8,1.8 0.5 −0.8,1.8
 166-168 654 1.8 1.9 0.5,3.3 1.9 0.5,3.3
 169-172 703 1.8 1.9 0.5,3.2 1.8 0.4,3.1
 173+ 509 3.5 3.6 2.3,4.8 <0.001 3.5 2.2,4.8 <0.001
Estimated date of delivery based on LMP
 <163 850 0 0 Ref 0 Ref
 163-165 723 0.3 0.4 −1.0,1.7 0.4 −1.0,1.8
 166-168 808 1.3 1.4 0.0,2.9 1.4 0.0,2.9
 169-172 839 0.6 0.6 −0.7,2.0 0.6 −0.7,2.0
 173+ 611 1.8 1.8 0.4,3.3 0.02 1.9 0.4,3.4 0.02

1Pregnancy length according to date of delivery estimated by ultrasound (US) (3146 pregnancies) and by first day of last menstrual period (LMP) (3831 pregnancies). 2Exclusion of pregnancies with induced onset of delivery (medically or by caesarean section). 3Adjusted for maternal age at baseline (HUNT 2 participation). 4Additionally adjusted for maternal age at birth, duration between Hunt 2 participation and delivery, maternal education, parity, maternal smoking, receiving social security benefits or not, and fetal sex. 5Additionally adjusted for pre-pregnancy maternal hypertension, diabetes mellitus, kidney and heart disease, BMI; systolic and diastolic blood pressure, concentration of glucose and lipids.

Pregnancies restricted to spontaneous onset of delivery2.

Myklestad et al.

Myklestad et al. BMC Pregnancy and Childbirth 2013 13:33   doi:10.1186/1471-2393-13-33

Open Data