Table 3: Factors associated with early cessation of exclusive breastfeeding, from Cox proportional hazard analysis of 2639 mother–infant pairs.
| Variable | No. of mothers* | Adjusted HR† (95% CI) | p value | |
|---|---|---|---|---|
| Maternal education | ||||
| Less than high school | 174 | 1.66 | (1.35–2.04) | < 0.001 |
| High school graduate | 619 | 1.35 | (1.18–1.54) | |
| College diploma | 509 | 1.25 | (1.08–1.43) | |
| University degree | 969 | 1.00 | (ref) | |
| Neighbourhood income quintile | ||||
| Highest | 654 | 1.00 | (ref) | < 0.001 |
| Upper-middle | 520 | 1.33 | (1.14–1.55) | |
| Middle | 584 | 1.38 | (1.19–1.59) | |
| Lower-middle | 541 | 1.27 | (1.10–1.48) | |
| Lowest | 340 | 1.35 | (1.13–1.60) | |
| Marital status | ||||
| Married or common-law | 1563 | 1.00 | (ref) | 0.001 |
| Single, divorced, widowed or separated | 654 | 1.24 | (1.10–1.41) | |
| Prepregnancy BMI | ||||
| Underweight | 65 | 0.91 | (0.66–1.23) | 0.001 |
| Normal | 808 | 1.00 | (ref) | |
| Overweight | 441 | 1.12 | (0.97–1.30) | |
| Obese | 410 | 1.43 | (1.23–1.65) | |
| Smoking status during pregnancy | ||||
| Nonsmoker during pregnancy | 1982 | 1.00 | (ref) | < 0.001 |
| Quit during pregnancy | 227 | 1.09 | (0.92–1.29) | |
| Smoker at admission for delivery | 430 | 1.39 | (1.21–1.60) | |
| Folic acid supplementation before conception | ||||
| Yes | 708 | 1.00 | (ref) | 0.04 |
| No | 1025 | 1.15 | (1.01–1.30) | |
| Parity | ||||
| Primiparous | 1202 | 1.00 | (ref) | < 0.001 |
| Multiparous | 1437 | 0.76 | (0.69–0.84) | |
| Early breast contact (< 1 h after birth) | ||||
| Yes | 1007 | 1.00 | (ref) | < 0.001 |
| No | 917 | 1.44 | (1.29–1.62) | |
| Intention to breastfeed | ||||
| Yes | 2319 | 1.00 | (ref) | < 0.001 |
| No | 136 | 1.78 | (1.44–2.16) | |
Note: BMI = body mass index, CI = confidence interval, HR = hazard ratio, ref = reference category. *The total number of women who initiated breastfeeding was 2907, but this analysis excluded 268 women who had missing values for smoking status and district health authority. †Adjusted for factors listed in the table, as well as the mother’s district health authority. “Missing” categories for maternal education, marital status, prepregnancy BMI, prepregnancy folic acid supplementation, breast contact within 1 hour, and intention to breastfeed were included in the model, but adjusted HRs are not shown.