Maternal body mass index and gestational weight gain and their association with perinatal outcomes in Viet Nam
Erika Ota, Megumi Haruna, Motoi Suzuki, Dang Duc Anh, Le Huu Tho, Nguyen Thi Thanh Tam, Vu Dinh Thiem, Nguyen Thi Hien Anh, Mitsuhiro Isozaki, Kenji Shibuya, Koya Ariyoshi, Sachiyo Murashima, Hiroyuki Moriuchi & Hideki Yanai
Volume 89, Number 2, February 2011, 127-136
Table 2. Ratio of the odds of delivering an infant too small for gestational age relative to the odds of delivering an infant with appropriate size for gestational age as a function of maternal characteristics, infant sex and gestational age at delivery, Nha Trang, Viet Nam, 2007–2008
| Characteristic | No.a/totalb (%) | Crude OR | 95% CI | P | Adjusted OR | 95% CI | P |
|---|---|---|---|---|---|---|---|
| Gestational weight gain (kg) | |||||||
| < 10 | 151/729 (20.7) | 2.08 | 1.63–2.64 | < 0.001 | 1.90 | 1.48–2.44 | < 0.001 |
| ≥ 10 but < 15 | 161/1405 (11.5) | 1.00 | – | 1.00 | – | ||
| ≥ 15 | 49/558 (8.8) | 0.68 | 0.49–0.95 | 0.024 | 0.74 | 0.52–1.05 | 0.086 |
| BMIc | |||||||
| Low | 141/742 (19.0) | 1.86 | 1.47–2.35 | < 0.001 | 1.95 | 1.52–2.50 | < 0.001 |
| Normal | 196/1749 (11.2) | 1.00 | – | 1.00 | – | ||
| High | 24/201 (11.9) | 1.07 | 0.68–1.69 | 0.755 | 0.95 | 0.60–1.52 | 0.844 |
| Maternal age (years) | |||||||
| < 24 | 136/812 (16.7) | 1.55 | 1.18–2.03 | 0.002 | 1.13 | 0.84–1.52 | 0.431 |
| 25–29 | 109/949 (11.5) | 1.00 | – | 1.00 | – | ||
| 30–34 | 67/587 (11.4) | 0.99 | 0.72–1.37 | 0.966 | 1.02 | 0.73–1.44 | 0.904 |
| ≥ 35 | 49/344 (14.2) | 1.28 | 0.89–1.84 | 0.182 | 1.24 | 0.84–1.82 | 0.281 |
| Parity | |||||||
| Primipara | 204/1400 (14.6) | 1.00 | – | 1.00 | – | ||
| Multipara | 157/1292 (12.2) | 0.81 | 0.65–1.01 | 0.066 | 0.78 | 0.60–1.02 | 0.073 |
| Income ( × 1 000 Vietnamese dong) | |||||||
| < 1 500 | 49/255 (19.2) | 1.26 | 0.88–1.80 | 0.201 | 1.08 | 0.75–1.56 | 0.688 |
| ≥ 1 500 but < 2 500 | 157/989 (15.9) | 1.00 | – | 1.00 | – | ||
| ≥ 2 500 but < 3 500 | 97/779 (12.5) | 0.75 | 0.57–0.99 | 0.042 | 0.85 | 0.64–1.13 | 0.271 |
| ≥ 3 500 | 58/669 (8.7) | 0.50 | 0.37–0.69 | < 0.001 | 0.67 | 0.48–0.95 | 0.025 |
| Education (years) | |||||||
| < 12 | 243/1506 (16.1) | 1.43 | 1.10–1.87 | 0.008 | 1.30 | 0.98–1.74 | 0.068 |
| 12 | 84/708 (11.9) | 1.00 | – | 1.00 | – | ||
| > 12 | 34/478 (7.1) | 0.57 | 0.38–0.86 | 0.008 | 0.67 | 0.43–1.04 | 0.071 |
| Total physical activityd in MET h/wk | |||||||
| < 25th percentile | 98/671 (14.6) | 0.96 | 0.71–1.30 | 0.797 | 0.89 | 0.65–1.22 | 0.460 |
| ≥ 25th but < 50th percentile | 103/681 (15.1) | 1.00 | – | 1.00 | – | ||
| ≥ 50th but < 75th percentile | 79/666 (11.9) | 0.76 | 0.55–1.04 | 0.082 | 0.88 | 0.64–1.23 | 0.460 |
| ≥ 75th percentile | 81/673 (12.0) | 0.77 | 0.56–1.05 | 0.100 | 0.98 | 0.70–1.35 | 0.878 |
| Smoking exposure | |||||||
| None | 215/1737 (12.4) | 1.00 | – | 1.00 | – | ||
| Passive indoor smoking | 146/955 (15.3) | 1.28 | 1.02–1.60 | 0.034 | 1.06 | 0.84–1.34 | 0.638 |
| Pre-eclampsia | 10/35 (28.6) | 2.63 | 1.25–5.52 | 0.011 | 3.14 | 1.43–6.90 | 0.004 |
| Infant sex (male = 1, female = 0) | 207/1419 (14.6) | 1.24 | 0.99–1.55 | 0.059 | 1.21 | 0.96–1.52 | 0.114 |
| Gestational age at delivery | – | 0.87e | 0.79–0.95 | 0.002 | 0.89 | 0.81–0.97 | 0.012 |
BMI, body mass index; CI, confidence interval; MET h/wk, metabolic equivalent hours per week; OR, odds ratio.
a This represents the number of infants too small for gestational age (n = 361) born to women with the characteristic.
b This figure represents the number of infants of appropriate size plus the number of infants too small for gestational age (n = 2692) born to women with the characteristic.
c BMI represents body weight in kilograms divided by body surface area in square metres. Categories: low BMI: < 18.5; normal BMI, ≥ 18.5 but < 23.0; high BMI, ≥ 23.0.
d There is one case with missing data for physical activity.
e The OR represents the change in the risk of delivering a small baby with each additional week of gestation.