Table 1 Differences between maternal and infant characteristics and volume of formula milk consumption at 3 mo of agea
| Â | Feeding groups | Â | |||
|---|---|---|---|---|---|
| Â | Overall | BM | LFM | HFM | P |
Maternal characteristics | Â | 610(55.5) | 363(33.2) | 120(11.0) | Â |
Age(years), n(%) | |||||
 17~25 | 134(12.4) | 83(13.6) | 42(11.6) | 9(7.5) | 0.022 |
 25~29 | 562(51.8) | 319(52.3) | 192(52.9) | 51(42.5) |  |
 30~34 | 305(28.1) | 156(25.6) | 99(27.3) | 50(41.7) |  |
 35~46 | 83(7.7) | 45(7.4) | 28(7.7) | 10(8.3) |  |
Educational level(years), n(%) | |||||
  ≤ 9 | 139(12.8) | 83(13.6) | 41(11.3) | 15(12.5) | 0.657 |
 10~12 | 248(22.9) | 129(21.1) | 90(24.8) | 29(24.3) |  |
 13~22 | 695(64.2) | 390(63.9) | 229(63.1) | 76(63.3) |  |
BMI before pregnancy(kg/m2), n(%) | |||||
 14.42~18.5 | 233(21.4) | 121(19.8) | 84(23.1) | 28(23.3) | 0.022 |
 18.5~23.9 | 722(66.2) | 416(68.2) | 238(65.6) | 68(56.7) |  |
 24~27.9 | 115(10.6) | 65(10.7) | 29(8.0) | 21(17.5) |  |
 28~31.25 | 20(1.8) | 7(1.1) | 10(2.8) | 3(2.5) |  |
Maternal gestational weight gain quartile (kg), n(%) | |||||
 2~13 | 275(25.3) | 154(25.2) | 84(23.1) | 37(30.8) | 0.132 |
 13.1~16.5 | 270(24.8) | 156(25.6) | 97(26.7) | 17(14.2) |  |
 16.6~20 | 307(28.2) | 171(28.0) | 97(26.7) | 39(32.5) |  |
 20.1~41 | 237(21.8) | 127(20.8) | 83(22.9) | 27(22.5) |  |
Cesarean, n(%) | |||||
 yes | 680(62.8) | 352(57.7) | 231(63.6) | 97(80.8) | <0.001 |
Maternal GDM, n(%) | |||||
 yes | 60(5.5) | 37(6.1) | 15(4.1) | 8(6.7) | 0.501 |
Return to work at postpartum 3Â month, n(%) | |||||
 yes | 121(11.1) | 39(6.4) | 57(15.7) | 25(20.8) | <0.001 |
Infant characteristics | |||||
Sex, n(%) | |||||
 Boy | 585(53.5) | 302(49.5) | 209(57.6) | 74(61.7) | 0.008 |
 Girl | 508(46.5) | 308(50.5) | 154(42.4) | 46(38.3) |  |
Infant gestational age at birth(wk), n(%) | |||||
 37~38 | 306(28.2) | 157(25.7) | 115(31.7) | 34(28.3) | 0.226 |
 39~40 | 700(64.6) | 407(66.7) | 217(60.0) | 76(63.3) |  |
 41~42 | 78(7.2) | 39(6.4) | 29(8.0) | 10(8.3) |  |
Age at introduction of solid foods(months), n(%) | |||||
  < 6 | 680(63.7) | 355(58.2) | 238(65.6) | 87(72.5) | 0.013 |
  ≥ 6 | 387(36.3) | 233(38.2) | 123(33.9) | 31(25.8) |  |
illness episodes, n(%) | |||||
 yes | 137(12.5) | 72(11.8) | 51(14.0) | 14(11.7) | 0.566 |
Daily sleep time at 3mo(h) | 14.96 ± 1.97b | 15.04 ± 1.9 | 14.83 ± 2.04 | 14.95 ± 2.1 | 0.282 |
Daily sleep time at 6mo(h) | 13.63 ± 1.48 | 13.66 ± 1.51 | 13.56 ± 1.47 | 13.71 ± 1.41 | 0.525 |
Formula volume intake (ml/d) P50(P10; P90) | 600(120 ;960) | 0 | 405(120;720) | 960(840;1120) | Â |