Table 1 Demographics characteristics of the study population according to vaginal bleeding and progesterone treated in early pregnancy(n = 6615)
Characteristics | Overall (n = 6615) | No bleeding in early pregnancy | Bleeding in early pregnancy | P | ||
|---|---|---|---|---|---|---|
Non-treatment (n = 4821) | Progesterone treatment(n = 376) | Non-treatment (n = 744) | Progesterone treatment(n = 674) | |||
Gestational age at enrollment, wk | 13.1(1.4) | 13.1(1.4) | 12.8(1.1) | 13.0(1.3) | 13.0(1.4) | < 0.001 |
Ethnology (Han Chinese) | 6456(97.6) | 4709(97.7) | 361(96.0) | 723(97.2) | 663(98.3) | 0.092 |
Pre-pregnancy BMI, kg/m2 | 20.8(2.7) | 20.6(2.6) | 21.5(3.1) | 20.9(2.7) | 21.2(3.1) | < 0.001 |
Maternal age, y | 28.2(3.5) | 28.0(3.4) | 28.1(3.4) | 28.4(3.6) | 28.8(3.6) | < 0.001 |
Education (≥ 16 schooling years) | 3606(54.5) | 2626(54.5) | 227(60.4) | 392(52.7) | 361(53.6) | 0.091 |
Average personal income (≥ 5000 CNY) | 3759(58.1) | 2755(58.5) | 202(55.2) | 421(57.3) | 381(57.9) | 0.614 |
Nulliparity (Yes) | 5598(84.6) | 4090(84.8) | 338(89.9) | 604(81.2) | 566(84.0) | 0.002 |
Gravidity(n = 1) | 3823(57.8) | 2920(60.6) | 202(53.7) | 368(49.5) | 333(49.4) | < 0.001 |
History of spontaneous abortion (Yes) | 653(9.9) | 412(8.6) | 54(14.4) | 84(11.3) | 103(15.3) | < 0.001 |
History of induced abortion (Yes) | 1705(25.8) | 1156(24.0) | 94(25.0) | 251(33.7) | 204(30.3) | < 0.001 |
Smoking before pregnancy (Yes) | 240(3.6) | 179(3.7) | 10(2.7) | 27(3.6) | 24(3.6) | 0.773 |
Drinking before pregnancy (Yes) | 116(1.8) | 67(1.4) | 11(2.9) | 22(2.9) | 16(2.4) | 0.002 |
Gestational age at delivery, wk | 39.1(1.5) | 39.2(1.4) | 39.1(1.5) | 38.8(1.8) | 38.9(1.5) | < 0.001 |
Gestational weight gain, kg | 16.1(4.7) | 16.1(4.6) | 16.1(5.0) | 16.1(4.9) | 15.9(5.0) | 0.748 |
Fetal gender (Male) | 3559(53.8) | 2613(54.2) | 200(53.2) | 390(52.4) | 356(52.8) | 0.753 |
Birth weight, g | 3333(442) | 3342(426) | 3347(464) | 3297(497) | 3307(471) | 0.021 |
Birth length, cm | 50.1(1.5) | 50.2(1.4) | 50.1(1.4) | 49.9(1.7) | 50.0(1.7) | < 0.001 |
Any breastfeeding at 12 months of age (Yes) (n = 3136) | 1090(34.8) | 800(34.8) | 64(37.0) | 123(34.5) | 103(33.7) | 0.905 |
WAZ at 12 months of age (n = 3181) | 0.78(0.11,1.27) | 0.78(0.11,1.21) | 0.74(0.11,1.21) | 0.72(0.15,1.21) | 0.70(0.11,1.21) | 0.553 |