TABLE 4

Duration of Exclusive Breastfeeding and Risk of Infectious Diseases in the First Year of Life

Duration of Breastfeeding≤6 mo, OR (95% CI)7–12 mo, OR (95% CI)
URTILRTIGIURTILRTIGI
Never breastfed1.001.001.001.001.001.00
Partially for <4 mo, not breastfed thereafter0.96 (0.76–1.21)1.01 (0.68–1.50)0.77 (0.52–1.15)0.98 (0.75–1.27)0.78 (0.55–1.09)0.94 (0.68–1.28)
Partially for 4–6 mo0.85 (0.67–1.070.89 (0.60–1.34)0.72 (0.48–1.09)1.03 (0.76–1.39)0.67 (0.47–1.02)1.01 (0.71–1.44)
Exclusively for 4 mo, not breastfed thereafter0.70 (0.41–1.20)0.39 (0.12–1.31)1.01 (0.44–2.38)1.79 (0.99–3.14)0.45 (0.17–1.19)1.16 (0.59–2.27)
Exclusively for 4 mo, partially breastfed thereafter0.65 (0.51–0.83)a0.50 (0.32–0.79)a0.41 (0.26–0.64)a0.88 (0.66–1.16)0.46 (0.31–0.69)a1.07 (0.77–1.49)
Exclusively breastfed for 6 mo0.37 (0.18–0.74)a0.33 (0.08–1.40)0.46 (0.14–1.59)0.63 (0.30–1.33)0.54 (0.18–1.58)0.93 (0.42–2.06)
P<.01<.01<.01NS<.01NS
  • Reference group is never-breastfed infants. Values were adjusted for maternal education, ethnicity, smoking, gestational age, birth weight, siblings, and day care attendance. Complete information about duration of exclusive breastfeeding, infectious diseases, and all confounders until the age of 6 months was available for 3504 infants (upper respiratory tract infections), 3489 infants (lower respiratory tract infections), and 3438 infants (gastrointestinal infections). For ages 7 to 12 months, complete information on breastfeeding and infectious diseases was available for 2958 infants (upper respiratory tract infections), 3027 infants (lower respiratory tract infections), and 2938 infants (gastrointestinal infections). URTI indicates upper respiratory tract infection; LRTI, lower respiratory tract infection; GI, gastrointestinal infection; NS, not significant.

  • a P <.01.