Table 1.

Maternal and offspring characteristics at baseline and follow-up according to level of participation.

Characteristics	Offspring not in follow-up	Offspring only filling out Web-based questionnaire	Offspring participating in clinical examination	p-Value
Maternal		n = 209		n = 242		n = 423
PFOA (ng/mL)a		3.7 (1.8)		3.7 (2.0)		3.7 (2.0)		0.68b
Prepregnancy BMI (kg/m2)		21.8 ± 3.8		21.1 ± 2.5		21.4 ± 3.0		0.06c
Nulliparous (%)		54		57		59		0.42d
Smoking during pregnancy (%)		49		36		37		0.01d
Male offspring at follow-up				n = 150		n = 170
BMI (kg/m2)e				22.7 ± 2.9		22.6 ± 2.9		0.62c
Waist circumference (cm)e				85.5 ± 10.6		83.5 ± 8.9		0.08c
Current smoker (%)				19		18		0.75d
Female offspring at follow-up				n = 92		n = 253
BMI (kg/m2)e				22.3 ± 3.2		21.5 ± 3.0		0.03c
Waist circumference (cm)e				79.8 ± 10.2		78.6 ± 9.7		0.32c
Current smoker (%)				21		17		0.45d
Based on the 874 mothers whose blood samples were analyzed for PFAAs in the Aarhus Birth Cohort (1988–1989). Values are median (IQR) for maternal PFOA concentration; otherwise, they are mean ± SD or %. aMaternal serum from gestational week 30. bKruskal–Wallis test of differences among participation groups. cF-test (type III) of differences among participation groups. dChi-square test of differences among participation groups. eComparison for offspring anthropometry is based on self-reported values.