Table 5—

Relationship between respiratory illness or infection type in the first year of life and duration of exclusive breastfeeding

Upper respiratory tract infections

Wheezing lower respiratory illness

Nonwheezing lower respiratory infection

p-value

2–3

p-value

≥4

p-value

≥2

p-value

≥2

p-value

Duration of exclusive breastfeeding^#

Never/>0 months

0.80 (0.56–1.13)

0.202

0.72 (0.52–0.99)

0.041

0.84 (0.54–1.31)

0.448

0.83 (0.53–1.30)

0.404

1.54 (1.05–2.25)

0.027

0.82 (0.51–1.32)

0.418

1.08 (0.51–2.28)

0.847

<2 months/≥2 months

0.93 (0.73–1.19)

0.577

1.10 (0.88–1.37)

0.388

1.40 (1.04–1.88)

0.028

1.08 (0.81–1.43)

0.615

1.41 (1.06–1.88)

0.018

0.89 (0.65–1.22)

0.481

0.92 (0.53–1.59)

0.771

<4 months/≥4 months

0.91 (0.73–1.12)

0.366

1.08 (0.88–1.31)

0.468

1.28 (0.97–1.69)

0.078

1.33 (1.03–1.71)

0.027

1.73 (1.32–2.28)

<0.0005

1.01 (0.77–1.32)

0.966

0.94 (0.59–1.51)

0.803

<6 months/≥6 months

0.74 (0.60–0.93)

0.008

0.97 (0.79–1.18)

0.755

1.25 (0.93–1.67)

0.140

1.26 (0.97–1.64)

0.080

1.98 (1.46–2.68)

<0.0005

0.98 (0.75–1.29)

0.897

1.39 (0.84–2.30)

0.196

^#: for each level of exposure, the stated odds ratio contrasts the odds of illness or infection (the number of illnesses or infections in the column headings compared with none) in individuals exposed at the time defined in column one compared with all later times
Data are presented as odds ratio (95% confidence interval), in separate analyses adjusted for sex, gestational age and maternal smoking at any stage of pregnancy