Table 1.

Subject demographics.

Female, number/totala (%)	49/86 (57.0)
Male, number/total (%)	37/86 (43.0)
Vaginal delivery, number/total (%)	74/86 (86.0)
Caesarean section, number/total (%)	12/86 (14.0)
Birth April–September, number/total (%)	46/86 (53.5)
Birth October–March, number/total (%)	40/86 (46.5)
Mother not smoking, number/total (%)	83/86 (96.5)
Father not smoking, number/total (%)	79/86 (91.9)
Older siblings, number/total (%)	47/86 (54.7)
Attending day care, number/total (%)	74/86 (86.0)
Gestation week, mean (SD, range)	39.9 (1.45, 36–43)
Birth weight, mean grams (SD, range)	3546 (510.0, 1,860–4,600)
Birth length, mean cm (SD, range)	50.3 (1.89, 45–55)
Breastfed fully, mean months (SD, range)	4.0 (1.72, 0–10)
Breastfed partially, mean months (SD, range)	9.3 (4.58, 0.75–28)
Mother’s age, mean years (SD, range)	32.2 (4.79, 22–43)
Father’s age, mean years (SD, range)	33.5 (5.23, 22–43)
Age at day care start, mean months (SD, range)	18.0 (3.08, 12–26)

^aNumber (n = 86) of the same subjects followed prospectively at 2, 5, and 10 years of age with available demographic data.