From: Exposure to cooking fuels and birth weight in Lanzhou, China: a birth cohort study
Characteristic | Gas | Coal | Biomass | Electromagnetic | Other | P* |
---|---|---|---|---|---|---|
N (%) | N (%) | N (%) | N (%) | N (%) | ||
Birth weight | Â | Â | Â | Â | Â | Â |
 LBW | 371(4.7) | 70(19.6) | 42(35.0) | 53(10.9) | 114(11.1) |  |
 NBW | 6965(88.1) | 270(75.4) | 73(60.8) | 408(83.8) | 865(84.6) | <0.001 |
 Macrosomia | 571(7.2) | 18(5.0) | 5(4.2) | 26 (5.3) | 44(4.3) |  |
Birth weight | Â | Â | Â | Â | Â | Â |
 SGA | 509(6.4) | 55(15.4) | 22(18.4) | 56(11.5) | 114(10.2) |  |
 AGA | 6232(78.8) | 264(73.7) | 88(73.3) | 377(77.4) | 814(79.6) | <0.001 |
 LGA | 1166(14.8) | 39(10.9) | 10(8.3) | 54(11.1) | 105(10.2) |  |
Preterm | Â | Â | Â | Â | Â | Â |
 No | 7334(92.8) | 267(74.6) | 78(65.0) | 417(85.6) | 889(86.9) |  |
 Yes | 573(7.2) | 91(25.4) | 42(35.0) | 70(14.4) | 134(13.1) | <0.001 |
Maternal age (years) | Â | Â | Â | Â | Â | Â |
 <25 | 1040(13.2) | 136(38.0) | 42(35.0) | 226(27.9) | 1580(22.1) |  |
 25–29 | 3939(49.8) | 108(30.2) | 42(35.0) | 438(43.1) | 4737(42.8) | <0.001 |
 ≥30 | 2928(37.0) | 114(31.8) | 36(30.0) | 359(29.0) | 3578(35.1) |  |
Highest education level | Â | Â | Â | Â | Â | Â |
 High school or less | 2706(34.2) | 302(84.4) | 108(90.0) | 277(56.9) | 473(46.2) |  |
 College or above | 5111(64.7) | 55(15.4) | 10(8.3) | 205(42.1) | 466(45.6) | <0.001 |
 Missing | 90(1.1) | 1(0.3) | 2(1.7) | 5(1.0) | 84(8.2) |  |
Family income (RMB per capita) | Â | Â | Â | Â | Â | Â |
 <3000 | 3788(47.9) | 264(73.7) | 99(82.5) | 330(67.8) | 495(48.4) |  |
 ≥3,000 | 3454(43.7) | 58(16.2) | 5(4.2) | 137(28.1) | 318(31.1) | <0.001 |
 Missing | 665(8.4) | 36(10.1) | 16(13.3) | 20(4.1) | 210(20.5) |  |
Maternal pre-pregnancy BMI (kg/m2) | Â | Â | Â | Â | Â | Â |
 ≤18.5 | 1640(20.7) | 63(17.6) | 16(13.2) | 93(19.1) | 208(20.3) |  |
 18.6–23.9 | 5276(66.7) | 228(63.7) | 67(55.8) | 336(69.0) | 593(58.0) |  |
 ≥24 | 863(10.9) | 36(10.0) | 24(20.0) | 49(10.1) | 71(6.9) | <0.001 |
 Missing | 128(1.7) | 31(8.7) | 13(10.8) | 9(1.8) | 151(14.8) |  |
Maternal weight gain during pregnancy (kg) | Â | Â | Â | Â | Â | Â |
 <15 | 2262(28.6) | 158(44.1) | 55(45.8) | 204(41.9) | 311(30.5) |  |
 15–18.5 | 2573(32.6) | 71(19.8) | 20(16.7) | 138(28.3) | 248(24.2) |  |
 >18.5 | 2910(36.9) | 89(24.9) | 25(20.8) | 131(26.9) | 298(29.1) | <0.001 |
 Missing | 162(2.9) | 40(11.2) | 20(16.7) | 14(2.9) | 166(16.2) |  |
Vitamin supplement during pregnancy | Â | Â | Â | Â | Â | Â |
 No | 963(12.2) | 117(32.7) | 49(40.8) | 82(16.8) | 255(24.9) |  |
 Yes | 6920(87.5) | 239(66.8) | 71(59.2) | 403(82.8) | 683 (66.8) | <0.001 |
 Missing | 24(0.3) | 2(0.5) | 0(0.0) | 2(0.4) | 85(8.3) |  |
Smoking (Active and passive) | Â | Â | Â | Â | Â | Â |
 No | 6416(81.1) | 259(72.3) | 91(75.8) | 257(73.3) | 844(82.5) |  |
 Yes | 1491(18.9) | 99(27.7) | 29(24.2) | 130(26.7) | 179(17.5) | <0.001 |
Alcohol during pregnancy | Â | Â | Â | Â | Â | Â |
 No | 7871(99.6) | 357(99.7) | 120(100.0) | 487(100.0) | 951(93.0) |  |
 Yes | 18(0.2) | 0(0.0) | 0(0.0) | 0(0.0) | 2(0.2) | 0.697 |
 Missing | 18(0.2) | 1(0.3) | 0(0.0) | 0(0.0) | 70(6.8) |  |
Gestational Diabetes | Â | Â | Â | Â | Â | Â |
 No | 7828(99.0) | 351(99.7) | 118(98.3) | 484(99.4) | 1013(99.0) |  |
 Yes | 79(1.0) | 1(0.3) | 2(1.7) | 3(0.6) | 10(1.0) | 0.539 |
Preeclampsia | Â | Â | Â | Â | Â | Â |
 No | 7710(97.5) | 316(88.3) | 101 (84.2) | 464(95.3) | 983(96.1) |  |
 Yes | 197(2.5) | 42(11.7) | 19(15.8) | 23(4.7) | 321(3.9) | <0.001 |
Parity | Â | Â | Â | Â | Â | Â |
 Primiparous | 5960(75.4) | 186(52.0) | 52(43.3) | 339(69.6) | 688(67.3) |  |
 Multiparous | 1947(24.6) | 172(48.0) | 68(56.7) | 148(30.4) | 335(32.7) | <0.001 |
Caesarean section | Â | Â | Â | Â | Â | Â |
 No | 4921(62.3) | 194(54.2) | 54(45.0) | 307(63.0) | 592(57.9) |  |
 Yes | 2927(37.0) | 160(44.7) | 65(54.2) | 178(36.6) | 417(40.8) | <0.001 |
 Missing | 59(0.7) | 4(1.1) | 1(0.8) | 2(0.4) | 14(1.3) |  |
Gender | Â | Â | Â | Â | Â | Â |
 Boy | 4162(52.6) | 203(56.7) | 69(56.7) | 257 (57.5) | 512(52.8) |  |
 Girl | 3732(47.2) | 155(43.3) | 51(43.3) | 226(42.5) | 509(46.4) | 0.190 |
 Missing | 13(0.2) | 0(0.0) | 0(0.0) | 4(0.0) | 2(0.8) |  |
Ventilation | Â | Â | Â | Â | Â | Â |
 No | 751(9.5) | 234(65.4) | 98(81.7) | 222(45.6) | 713(69.7) |  |
 Yes | 7156(90.5) | 124(34.6) | 22(18.3) | 265(54.4) | 310(30.3) | <0.001 |