Table 2.
Characteristics of all participants (n = 152) † , non‐retainers and retainers at 6 (n = 129) and 12 (n = 114) months
| Characteristic | All (n = 152) † | WR ‡ at 6 months (n = 129) | P‐value | (WR) ‡ at 12 months (n = 114) | P‐value | Test | ||
|---|---|---|---|---|---|---|---|---|
| Baseline | ≤0 kg (n = 29) | >0 kg (n = 100) | ≤0 kg (n = 37) | >0 kg (n = 77) | ||||
| Age § | 28.6 (25.2–32.8) | 29.8 (26.7–36.6) | 28.9 (25.6–31.9) | 0.17 | 29.4 (26.2–34.0) | 29.6 (26.3–33.2) | 0.70 | Rank sum |
| Height § | 164.3 (160.1–169.2) | 165.2 (161.5–170.0) | 164.4 (160.0–168.2) | 0.34 | 162.9 (158.8–166.9) | 165.0 (160.0–16.9) | 0.37 | Rank sum |
| Born in Australia, n (%) | 142 (93.4) | 25 (86.2) | 94 (94.0) | 0.16 | 35 (94.6) | 70 (93.5) | 0.59 | Fishers exact |
| Married or de facto, n (%) | 132 (86.8) | 25 (86.2) | 87 (87.0) | 0.56 | 32 (86.5) | 68 (88.3) | 0.78 | Chi2/Fishers exact |
| Education ≥ year 12, n (%) | 104 (71.7) | 21 (72.4) | 71 (71.0) | 0.70 | 27 (73.0) | 59 (76.6) | 0.69 | Chi2 |
| Infant sex, n (%) male | 77 (50.7) | 17 (58.6) | 49 (49.0) | 0.36 | 15 (40.5) | 41 (53.3) | 0.20 | Chi2 |
| Smoking, n (%) | 18 (11.8%) | 3 (10.3) | 13 (13.0) | 0.49 | 3 (8.1) | 9 (11.7) | 0.41 | Exact |
| Weight variables | ||||||||
| Pre‐pregnancy weight § | 65.0 (58.0–78.8) | 75.0 (63.0–83.5) | 65.0 (56.5–75.5) | <0.01* | 66.0 (59.0–80.0) | 65.0 (58.0–76.0) | 0.62 | Rank sum |
| Pre‐pregnancy BMI § | 24.3 (21.3–29.0) | 25.8 (21.1–26.6) | 23.6 (21.1–26.5) | 0.02* | 23.6 (21.3–30.1) | 24.1 (21.1–26.9) | 0.60 | Rank sum |
| GWG § , ¶ | 12.7 (8.9–17.1) | 8.8 (6.4–12.2)* | 14.6 (10.5–18.1) | <0.01* | 10.3 (6.8–14.3)* | 14.7 (1142–18.1) | <0.001* | Rank sum |
| Weight at each time § | 69.2 (60.3–79.6) | 71.0 (61.3–83.4) | 69.6 (60.5–80.8) | 0.90 | 62.9 (57.1–78.5)* | 70.4 (63.1–83.5) | 0.01* | Rank sum |
| BMI at each time § | 25.5 (22.4–30.4) | 24.8 (21.8–31.1) | 25.5 (22.6–30.4) | 0.72 | 22.7 (20.8–29.1)* | 26.1 (23.3–30.6) | 0.01* | Rank sum |
| WR at each time § | 2.3 (−0.7–6.8) | −1.8 (−5.7–1.35) | 4.3 (2–8) | <0.01* | −1.8 (−4.4−0.9) | 4.5 (2.1–8.9) | <0.001* | Rank sum |
| Breastfeeding variables | ||||||||
| Initiated breastfeeding, n (%) | 136 (93.2) | 27 (93.1) | 94 (94.0) | 0.57 | 36 (97.3) | 71 (92.2) | 0.27 | Fishers exact |
| Exclusive breastfeeding at 3 months n (%) | 76 (52.1) | 17 (58.6) | 51 (52.0) | 0.82 | 25 (67.6)* | 37 (48.1) | 0.046* | Fishers exact |
| Any breastfeeding at each time n (%) | 34 (28.8) | 16 (55.2) | 57 (57.0) | 0.86 | 14 (37.8) | 20 (26.0) | 0.20 | Chi2 |
| Total weeks breastfeeding § | 29.0 (7.0–52.0) | 7.0 (0.0–14.0) | 26.0 (0.6–26.0) | 0.17 | 40.0 (7.0–52.0) | 26.0 (8.0–52.0) | 0.36 | Rank sum |
| Number of weeks exclusively breastfeeding § | 24.0 (20.0–26.0) | 24.0 (21.0–25.0) | 24.0 (20.0–26.0) | 0.50 | 24.0 (20.0–25.0) | 24.0 (20.0–26.0) | 0.59 | Rank sum |
*Indicates statistical significance α < 0.05. †This excludes those who withdrew during pregnancy and who were enrolled but did not attend any post‐partum visits. ‡Weight retained is pre‐pregnancy weight (kg) subtracted from weight at three, six, nine and 12 months post‐partum. §Median (25th–75th percentile) reported for non‐normally distributed continuous data. ¶Gestational weight gain (GWG) is pre‐pregnancy body weight subtracted from weight at 36 weeks gestation.