From: Lactation and cardiovascular risk factors in mothers in a population-based study: the HUNT-study
 | Nulliparous women | Parous women | ||||
---|---|---|---|---|---|---|
 |  | Lifetime duration of lactation (months) | ||||
Variables a | n = 5,020 | 0 n = 705 | 1 – 6 n = 4,421 | 7 – 12 n = 5,401 | 13 – 23 n = 6,266 | ≥ 24 n = 4,575 |
Age, yrs, mean (SD) | 44.7 (21.6) | 50.7 (13.7) | 48.4 (14.5) | 49.3 (14.9) | 50.1 (14.8) | 53.8 (15.7) |
Age at delivery of first child, yrs, mean (SD) | - | 24.2 (5.1) | 23.3 (4.4) | 23.3 (4.2) | 23.4 (3.9) | 23.2 (3.7) |
Parity, | ||||||
Para 1 (%) | - | 29.9 | 30.8 | 17.2 | 2.5 | 0.4 |
Para 2 (%) | - | 38.3 | 45.1 | 44.0 | 45.1 | 12.9 |
Para 3 (%) | - | 21.7 | 17.4 | 26.7 | 35.0 | 41.2 |
Para 4 or greater (%) | - | 10.1 | 6.8 | 12.0 | 17.5 | 45.5 |
University/college education (%)b | 26.4 | 13.2 | 13.4 | 18.0 | 21.7 | 22.4 |
Never smoked (%) | 62.2 | 37.3 | 36.7 | 45.7 | 50.9 | 60.5 |
High physical activityc,d (%) | 28.7 | 14.6 | 17.6 | 18.2 | 20.9 | 18.2 |
Unmarried/divorced (%) | 61.6 | 24.4 | 28.7 | 23.2 | 16.5 | 11.1 |
Hypertensione (%) | 37.5 | 47.2 | 36.3 | 37.5 | 37.5 | 44.9 |
Obesityf (%) | 17.0 | 27.9 | 18.7 | 18.0 | 16.3 | 21.2 |
Diabetes (%)g | 3.0 | 4.4 | 1.9 | 2.0 | 2.4 | 3.7 |