Table 1 Infant, parent and household characteristics at time of enrollment ^a

 Age, days

31.8 ± 2.6

31.5 ± 1.8

31.6 ± 2.0

 Gestational age, weeks

39.1 ± 1.1

38.8 ± 1.3

38.9 ± 1.2

 Weight, gram

4274 ± 332

4061 ± 505

4167 ± 435

 Length, cm

52.6 ± 1.8

51.8 ± 1.5

52.2 ± 1.7

 BMI z-score

0.97 ± 1.12

0.82 ± 0.86

0.90 ± 0.99

 Head circumference, cm

36.7 ± 0.8

35.9 ± 1.0

36.2 ± 0.9

 Type of delivery, % cesarean

3 (15.0)

6 (30.0)

9 (22.5)

 Previously breastfed, % yes

18 (90.0)

17 (85.0)

35 (87.5)

 Prior breastfeeding, days

9.9 ± 7.0

9.4 ± 4.4

9.6 ± 5.8

 Mother’s age, years

25.9 ± 5.0

26.3 ± 6.1

26.1 ± 5.5

 Mother’s highest level of education

  Vocational school

7 (35.0)

10 (50.0)

17 (42.5)

  High school

2 (10.0)

1 (5.0)

3 (7.5)

 Any college

11(55.0)

9 (45.0)

20 (50)

 Employed/self-employed, % full-time

6 (30.0)

8 (40.0)

14 (35.0)

 Father’s age, years

28.9 ± 6.4

29.2 ± 6.5

29.0 ± 6.3

 Father’ highest level of education^c

  Vocational school

13 (65.0)

11 (55.0)

24 (60.0)

  High school

1 (5.0)

1 (5.0)

2 (5.0)

  Any college

6 (30.0)

6 (30.0)

12 (15.0)

 Employed/self-employed, % full-time

17 (85.0)

18 (90.0)

35 (87.5)

 Number of children (less than 18 years old) living in the household

1 child

2 (10.0)

0 (00.0)

2 (5.0)

2 children

4 (20.0)

6 (30.0)

10 (25.0)

3 children

8 (40.0)

7 (35.0)

15 (37.5)

4 children

4 (20.0)

5 (25.0)

9 (22.5)

5 or more children

2 (10.0)

2 (10.0)

4 (10.0)

 Household monthly income

  10,001–20,000 Pesos

12 (60.0)

12 (60.0)

24 (60.0)

  20,001–35,000 Pesos

6 (30.0)

4 (20.0)

10 (25.0)

  35,001–60,000 Pesos

2 (10.0)

4 (20.0)

6 (15.0)