The association between place of birth (home birth vs hospital birth) and breast feeding in GUI (n=10 604) and UKMCS (n=17 521) cohorts
| Breast feeding time point | Study population | Unadjusted analysis | Adjusted analysis | ||||
|---|---|---|---|---|---|---|---|
| OR | 95% CI | p Value | OR | 95% CI | p Value | ||
| Initiation | GUI | 2.23 | 1.53 to 3.24 | <0.0001 | 1.9 | 1.19 to 3.02 | <0.0001 |
| Initiation | UKMCS | 2.31 | 1.74 to 3.05 | <0.0001 | 2.49 | 1.84 to 3.44 | 0.011 |
| 8 weeks | GUI | 2.25 | 1.61 to 3.13 | <0.0001 | 1.78 | 1.18 to 2.69 | 0.0029 |
| 8 weeks | UKMCS | 2.69 | 2.14 to 3.38 | <0.0001 | 2.49 | 1.92 to 3.26 | <0.0001 |
| 6 months | GUI | 2.23 | 1.61 to 3.09 | <0.0001 | 1.85 | 1.23 to 2.77 | 0.0058 |
| 6 months | UKMCS | 3.3 | 2.66 to 4.10 | <0.0001 | 2.9 | 2.25 to 3.73 | <0.0001 |
| 6 months: exclusive | GUI | 2.94 | 2.01 to 4.31 | <0.0001 | 2.77 | 1.78 to 4.33 | 0.0073 |
| 6 months: exclusive | UKMCS | 3.17 | 1.79 to 5.60 | <0.0001 | 2.24 | 1.14 to 4.03 | <0.0001 |
The ORs and corresponding 95% CIs are shown for any breast feeding at birth, 8 weeks and 6 months, and exclusive breast feeding for 6 months, according to place of birth (home vs hospital birth).
The strongest association in GUI is with exclusive breast feeding for 6 months, adjusted OR=2.77 (1.78 to 4.33), and in UKMCS it is with breast feeding for 6 months, 2.90 (2.25 to 3.73); the weakest association in GUI is with breast feeding for 8 weeks, 1.78 (1.18 to 2.69), and in UKMCS it is with breast feeding exclusively for 6 months, 2.24 (1.14 to 4.03).
Other covariates which were associated with breast feeding initiation and at all assessed time points included maternal factors; older maternal age and perception of low support (GUI); birth factors; later gestational age and heavier birth weight; and socioeconomic factors; higher education level, higher household income and later timing of return to work. Negatively associated covariates included maternal factors; Irish or British ethnicity, higher parity, smoking status: smoker, higher alcohol consumption and higher BMI; socioeconomic factors; long-term unemployment; birth characteristics: caesarean mode of delivery and infant characteristics: male infant.
BMI, body mass index; GUI, Growing Up in Ireland; UKMCS, UK Millennium Cohort Study.