Table 1.

Descriptive data of study population (N = 1477)

	N	Breastfed children	N	Non-breastfed children	P
Child characteristics
Female gender, n (%)	936	489 (52.2%)	541	244 (45.1%)	0.009
Birth-weight (kg)	909	3.64 ± 0.47	530	3.59 ± 0.50	0.141
Gestational age (weeks)	931	40.1 ± 1.2	537	39.9 ± 1.3	< 0.001
Ethnicity (%)	873		504		0.009
Dutch		810 (92.8%)		485 (96.2%)
Non-Dutch		63 (7.2%)		19 (3.8%)
Age at PA measurement (years)	622	5.64 ± 0.79	284	5.67 ± 0.77	0.661
Age at dietary measurement (years)	874	5.81 ± 0.33	516	5.85 ± 0.33	0.118
BMI z-score at 5 years	836	0.20 ± 0.80	491	0.36 ± 0.90	0.002
Overweight at 5 years, n (%)	836	109 (13.0%)	491	92 (18.7%)	0.007
Parental characteristics
Age father at birth (years)	890	33.89 ± 4.88	514	33.52 ± 4.44	0.261
Age mother at birth (years)	932	31.19 ± 4.22	540	30.80 ± 4.13	0.050
BMI father before pregnancy	862	25.32 ± 3.15	499	25.92 ± 3.55	0.002
BMI mother before pregnancy	889	24.14 ± 4.33	513	26.17 ± 5.22	< 0.001
Household income, n (%)	834		463		< 0.001
≤ €1150/month		25 (3.0%)		16 (3.5%)
€1151–3050/month		512 (61.4%)		342 (73.9%)
€3051–3500/month		171 (20.5%)		72 (15.6%)
€3501 or more/month		126 (15.1%)		33 (7.1%)
Educational level father, n (%)	886		511		< 0.001
Low/middle		530 (59.8%)		396 (77.5%)
High [(applied) university]		356 (40.2)		115 (22.5%)
Educational level mother, n (%)	907		524		< 0.001
Low/middle		462 (50.9%)		398 (76%)
High [(applied) university]		445 (49.1%)		126 (24%)
Smoking during pregnancy, n(%)	926		534		0.001
Yes		92 (9.9%)		85 (15.9%)
No		834 (90.1%)		449 (84.1%)

Bold: p < 0.05, N_breastfed = 936, N_{non-breastfed} = 541

Results are shown as mean ± SD or n (%)