Table 1.
Characteristics of the Participants in Northwest China During 2010–2013
| Characteristics | N | LBW | SGA | PTB | Birth Defects |
|---|---|---|---|---|---|
| 468 (3.54) | 1910 (14.44) | 368 (2.78) | 315 (2.38) | ||
| Childbearing age (year) | |||||
| <25 | 3410 (25.77) | 119 (3.49) | 522 (15.31) | 86 (2.52) | 86 (2.52) |
| 25–29 | 5603 (42.35) | 193 (3.44) | 801 (14.30) | 156 (2.78) | 125 (2.23) |
| 30–34 | 2691 (20.34) | 97 (3.60) | 356 (13.23) | 76 (2.82) | 67 (2.49) |
| ≥35 | 1527 (11.54) | 59 (3.86) | 231 (15.13) | 50 (3.27) | 37 (2.42) |
| Maternal education | |||||
| Primary school or lower | 2494 (18.85) | 130 (5.21)* | 490 (19.65)* | 69 (2.77) | 60 (2.41) |
| Secondary school | 7581 (57.30) | 252 (3.32) | 1105 (14.58) | 204 (2.69) | 184 (2.43) |
| Senior high school or higher | 3156 (23.85) | 86 (2.72) | 315 (9.98) | 95 (3.01) | 71 (2.25) |
| Residence | |||||
| Rural | 11,434 (86.42) | 426 (3.73)* | 1750 (15.31)* | 311 (2.72) | 279 (2.44) |
| Urban | 1797 (13.58) | 42 (2.34) | 160 (8.90) | 57 (3.17) | 36 (2.00) |
| Family economic status | |||||
| Low | 3010 (22.75) | 117 (3.89) | 446 (14.82)* | 81 (2.69) | 80 (2.66) |
| Middle | 7376 (55.75) | 271 (3.67) | 1119 (15.17) | 214 (2.90) | 165 (2.24) |
| High | 2845 (21.50) | 80 (2.81) | 345 (12.13) | 73 (2.57) | 70 (2.46) |
| Maternal Occupation | |||||
| Peasant/housework | 9875 (74.64) | 377 (3.82)* | 1532 (15.51)* | 266 (2.69) | 243 (2.46) |
| Others | 3356 (25.36) | 91 (2.71) | 378 (11.26) | 102 (3.04) | 72 (2.15) |
| Passive smoking | |||||
| Yes | 3647 (27.56) | 138 (3.78) | 563 (15.44)* | 100 (2.74) | 118 (3.24)* |
| No | 9584 (72.44) | 330 (3.44) | 1347 (14.05) | 268 (2.80) | 197 (2.06) |
| Folic Acid Supplement | |||||
| Yes | 8121 (61.38) | 247 (3.04)* | 1042 (12.83)* | 211 (2.60) | 183 (2.25) |
| No | 5110 (38.62) | 221 (4.32) | 868 (16.99) | 157 (3.07) | 132 (2.58) |
| Iron Supplement | |||||
| Yes | 608 (4.60) | 13 (2.14) | 59 (9.70)* | 17 (2.80) | 6 (0.99)* |
| No | 12,623 (95.40) | 455 (3.60) | 1851 (14.66) | 351 (2.78) | 309 (2.45) |
| Frequency of antenatal care visits | |||||
| ≥5 | 8304 (62.76) | 249 (3.00)* | 1030 (12.40)* | 237 (2.85) | 193 (2.32) |
| <5 | 4927 (37.24) | 219 (4.44) | 880 (17.86) | 131 (2.66) | 122 (2.48) |
| Maternal taking medicine | |||||
| Yes | 2483 (18.77) | 112 (4.51)* | 360 (14.50) | 98 (3.95)* | 114 (4.59)* |
| No | 10,748 (81.23) | 356 (3.31) | 1550 (14.42) | 270 (2.51) | 201 (1.87) |
| Infant gender | |||||
| Male | 7522 (56.85) | 221 (2.94)* | 1044 (13.88)* | 214 (2.84) | 195 (2.59) |
| Female | 5709 (43.15) | 247 (4.33) | 866 (15.17) | 154 (2.70) | 120 (2.10) |
Notes: The variables are presented as n (%); *P<0.05.
Abbreviations: LBW, low birth weight; SGA, small for gestational age; PTB, preterm birth.