Table 2. Maternal inter-pregnancy weight change and risks of low Apgar score (0–6) at 5 min, neonatal seizures, and meconium aspiration: live singleton second term infants of women in Sweden 1992–2012.
| Outcome | Inter-pregnancy Weight Change (kg/m2) | Number with Outcome | Rate/1,000 | OR (95% CI) | |
|---|---|---|---|---|---|
| Crude a | Adjusted b | ||||
| Low Apgar score (0–6) at 5 min | <−2 | 96 | 4.99 | 1.10 (0.89–1.36) | 0.84 (0.67–1.04) |
| −2 to <−1 | 155 | 4.34 | 0.95 (0.80–1.13) | 0.90 (0.76–1.07) | |
| −1 to <1 | 878 | 4.54 | 1.00 | 1.00 | |
| 1 to <2 | 458 | 5.41 | 1.19 (1.06–1.33) | 1.14 (1.02–1.28) | |
| 2 to <4 | 407 | 6.36 | 1.40 (1.25–1.58) | 1.26 (1.11–1.42) | |
| ≥4 | 178 | 7.54 | 1.66 (1.42–1.96) | 1.33 (1.12–1.58) | |
| Data missing | 564 | 5.60 | |||
| Per 1-kg/m2 change in BMI | 1.08 (1.03–1.14) | 1.07 (1.04–1.09) | |||
| Neonatal seizures | <−2 | 30 | 1.53 | 1.48 (1.01–2.18) | 1.18 (0.79–1.76) |
| −2 to <−1 | 39 | 1.07 | 1.04 (0.74–1.43) | 1.00 (0.71–1.42) | |
| −1 to <1 | 203 | 1.03 | 1.00 | 1.00 | |
| 1 to <2 | 105 | 1.22 | 1.18 (0.93–1.49) | 1.13 (0.89–1.44) | |
| 2 to <4 | 108 | 1.65 | 1.61 (1.27–2.03) | 1.46 (1.14–1.86) | |
| ≥4 | 44 | 1.82 | 1.77 (1.28–2.45) | 1.42 (1.00–2.02) | |
| Data missing | 120 | 1.17 | |||
| Per 1-kg/m2 change in BMI | 1.00 (0.90–1.12) | 1.05 (1.01–1.09) | |||
| Meconium aspiration | <−2 | 10 | 0.51 | 0.86 (0.45–1.64) | 0.53 (0.25–1.10) |
| −2 to <−1 | 19 | 0.52 | 0.88 (0.54–1.42) | 0.84 (0.52–1.37) | |
| −1 to <1 | 117 | 0.59 | 1.00 | 1.00 | |
| 1 to <2 | 51 | 0.59 | 0.99 (0.72–1.38) | 0.95 (0.68–1.32) | |
| 2 to <4 | 54 | 0.83 | 1.39 (1.01–1.92) | 1.14 (0.81–1.60) | |
| ≥4 | 38 | 1.58 | 2.66 (1.84–3.83) | 1.78 (1.19–2.68) | |
| Data missing | 78 | 0.76 | |||
| Per 1-kg/m2 change in BMI | 1.15 (1.02–1.29) | 1.11 (1.06–1.17) | |||
Women whose first infant had a low Apgar score (0–6) at 5 min (n = 5,852), neonatal seizures (n = 1,325), or meconium aspiration (n = 1,380) are excluded from respective analyses.
aCrude analyses are based on the following number of second births: Apgar score, n = 420,429 infants, of whom 2,172 had a low Apgar score (0–6) at 5 min; neonatal seizures, n = 428,945, of whom 529 had neonatal seizures; meconium aspiration, n = 428,908, of whom 289 had meconium aspiration.
bAdjusted for BMI in first pregnancy, maternal height, smoking in second pregnancy, maternal age at second birth, inter-pregnancy interval, mother’s education, mother’s country of birth, and year of second birth. Adjusted analyses are based on second births with complete information on maternal covariates (Apgar score: 412,938 infants, of whom 2,128 had Apgar score 0–6 at 5 min; neonatal seizures: 421,250 infants, of whom 518 had neonatal seizures; meconium aspiration: 421,206 infants, of whom 280 had meconium aspiration).