Table 1 Characteristics of participants [\( \overset{-}{x}\pm s \)/n (%)]
| Â | n | Urban | Rural | ||
|---|---|---|---|---|---|
Before reform | After reform | Before reform | After reform | ||
Age (years) | |||||
|  | 28.67 ± 5.48 | 28.37 ± 4.24 | 28.60 ± 5.19 | 28.59 ± 5.69 | 28.82 ± 5.81 |
  ≤ 25 | 751 | 57(25.56) | 195(27.46) | 149(34.10) | 350(34.05) |
 26–30 | 878 | 107(47.98) | 302(42.54) | 137(31.35) | 332(32.30) |
  ≥ 31 | 769 | 59(26.46) | 213(30.00) | 151(34.55) | 346(33.65) |
Education | |||||
  ≤ Primary school | 451 | 8(3.59) | 78(11.02) | 133(30.57) | 232(22.59) |
 Middle school | 1318 | 84(37.67) | 371(52.40) | 243(55.86) | 620(60.37) |
  ≥ High school | 624 | 131(58.74) | 259(36.58) | 59(13.56) | 175(17.04) |
Employment | |||||
 No | 532 | 95(43.38) | 218(30.79) | 372(85.32) | 872(84.91) |
 Yes | 1858 | 124(56.62) | 490(69.21) | 64(14.68) | 155(15.09) |
Annual Household income (Ren Min Bi) | |||||
|  | 22,402 ± 18,828 | 16,718 ± 9723 | 32,841 ± 24,662 | 9985 ± 7107 | 21,675 ± 14,717 |
 Poorest | 479 | 99(44.80) | 87(12.27) | 224(51.49) | 69(6.71) |
 Poorer | 479 | 54(24.43) | 132(18.62) | 108(24.83) | 185(18.00) |
 Media | 478 | 40(18.10) | 146(20.59) | 58(13.33) | 234(22.76) |
 Richer | 479 | 22(9.95) | 164(23.13) | 22(5.06) | 271(26.36) |
 Richest | 478 | 6(2.71) | 180(25.39) | 23(5.29) | 269(26.17) |
Delivery institution | |||||
 Secondary and above | 1948 | 144(64.57) | 661(93.10) | 201(46.00) | 942(91.63) |
  ≤ Primary institution | 450 | 79(35.43) | 49(6.90) | 236(54.00) | 86(8.37) |
Delivery way | |||||
 Vaginal | 1673 | 156(98.73) | 434(61.47) | 329(95.64) | 754(73.42) |
 Caesarean | 562 | 2(1.27) | 272(38.53) | 15(4.36) | 273(26.58) |
Parity | |||||
  ≤ 1 | 1381 | 193(86.94) | 433(60.99) | 258(59.58) | 497(48.44) |
  ≥ 2 | 1010 | 29(13.06) | 277(39.01) | 175(40.42) | 529(51.56) |
Weight of newborn | |||||
 Low birthweight | 100 | 2(0.90) | 32(4.51) | 9(2.06) | 57(5.54) |
 Normal birthweight | 2298 | 221(99.10) | 678(95.49) | 428(97.94) | 971(94.46) |