Background
Methods
Study design and participants
Data collection
Outcomes
Statistical analysis
Results
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 |
Outcomes | Vaginal bleeding | Progesterone | ||
---|---|---|---|---|
No | Yes | Non-treatment | Treatment | |
Very preterm (< 34 weeks of gestation) | ||||
N(%) | 24(0.5) | 23(1.6) | 35(0.6) | 12(1.1) |
Unadjusted model | 1 | 3.55(2.00–6.32) | 1 | 1.83(0.95–3.53) |
Adjusted model I* | 1 | 3.50(1.83–6.68) | 1 | 0.84(0.20–1.78) |
Adjusted model IIa | 1 | 3.56(1.86–6.83) | 1 | 0.85(0.40–1.79) |
Preterm (< 37 weeks of gestation) | ||||
N(%) | 171(3.3) | 90(6.4) | 207(3.7) | 54(5.1) |
Unadjusted model | 1 | 1.99(1.53–2.59) | 1 | 1.40(1.03–1.91) |
Adjusted model I* | 1 | 1.95(1.45–2.63) | 1 | 0.96(0.68–1.36) |
Adjusted model IIa | 1 | 1.97(1.46–2.65) | 1 | 0.96(0.68–1.37) |
SGA | ||||
N(%) | 325(6.3) | 105(7.4) | 351(6.3) | 79(7.5) |
Unadjusted model | 1 | 1.20(0.95–1.51) | 1 | 1.21(0.94–1.56) |
Adjusted model I* | 1 | 1.21(0.93–1.57) | 1 | 1.19(0.89–1.60) |
Adjusted model IIb | 1 | 1.23(0.94–1.60) | 1 | 1.19(0.88–1.59) |
LBW | ||||
N(%) | 104(2.0) | 63(4.4) | 126(2.3) | 41(3.9) |
Unadjusted model | 1 | 2.28(1.66–3.13) | 1 | 1.75(1.23–2.51) |
Adjusted model I* | 1 | 2.13(1.47–3.08) | 1 | 1.18(0.78–1.79) |
Adjusted model IIb | 1 | 1.24(0.78–1.97) | 1 | 1.63(0.98–2.72) |
WAZ < -1 at 12 months of age (n = 3181) | ||||
N(%) | 70(2.8) | 29(4.3) | 80(3.0) | 19(3.9) |
Unadjusted model | 1 | 1.56(1.01–2.37) | 1 | 1.33(0.80–2.22) |
Adjusted model I* | 1 | 1.53(0.93–2.53) | 1 | 1.08(0.60–1.93) |
Adjusted model IIc | 1 | 1.40(0.83–2.35) | 1 | 1.13(0.62–2.05) |
Outcomes | Bleeding in early pregnancy | |
---|---|---|
Non-treatment | Progesterone treatment | |
Very preterm (< 34 weeks of gestation) | ||
N(%) | 14(1.9) | 9(1.3) |
Unadjusted model | 1 | 0.71(0.31–1.64) |
Adjusted model I* | 1 | 0.63(0.27–1.48) |
Adjusted model IIa | 1 | 0.61(0.26–1.43) |
Preterm (< 37 weeks of gestation) | ||
N(%) | 52(7.0) | 38(5.6) |
Unadjusted model | 1 | 0.80(0.52–1.23) |
Adjusted model I* | 1 | 0.78(0.51–1.21) |
Adjusted model IIa | 1 | 0.77(0.50–1.19) |
SGA | ||
N(%) | 51(6.9) | 54(8.0) |
Unadjusted model | 1 | 1.18(0.80–1.76) |
Adjusted model I* | 1 | 1.19(0.80–1.79) |
Adjusted model IIb | 1 | 1.18(0.79–1.77) |
LBW | ||
N(%) | 32(4.3) | 31(4.6) |
Unadjusted model | 1 | 1.07(0.65–1.78) |
Adjusted model I* | 1 | 1.05(0.63–1.75) |
Adjusted model IIb | 1 | 1.83(0.93–3.60) |
WAZ < -1 at 12 months of age (n = 675) | ||
N(%) | 13(3.6) | 16(5.1) |
Unadjusted model | 1 | 1.45(0.69–3.06) |
Adjusted model I* | 1 | 1.43(0.67–3.06) |
Adjusted model IIc | 1 | 1.60(0.72–3.57) |
Outcomes | Overall | No bleeding in early pregnancy | Bleeding in early pregnancy | ||
---|---|---|---|---|---|
Non-treatment | Progesterone treatment | Non-treatment | Progesterone treatment | ||
Very preterm (< 34 weeks of gestation) | |||||
N (%) | 47(0.7) | 21(0.4) | 3(0.8) | 14(1.9) | 9(1.3) |
Adjusted model I* | 1 | 1.69(0.49–5.78) | 4.16(2.09–8.26) | 2.73(1.24–6.05) | |
Adjusted model IIa | 1 | 1.74(0.51–5.98) | 4.25(2.13–8.49) | 2.79(1.26–6.18) | |
Preterm (< 37 weeks of gestation) | |||||
N (%) | 261(4.0) | 155(3.2) | 16(4.3) | 52(7.0) | 38(5.6) |
Adjusted model I* | 1 | 1.32(0.78–2.25) | 2.18(1.57–3.02) | 1.74(1.20–2.51) | |
Adjusted model IIa | 1 | 1.35(0.79–2.30) | 2.21(1.59–3.07) | 1.74(1.21–2.52) | |
SGA | |||||
N (%) | 430(6.5) | 300(6.2) | 25(6.7) | 51(6.9) | 54(8.0) |
Adjusted model I* | 1 | 1.17(0.77–1.80) | 1.20(0.88–1.63) | 1.44(1.06–1.96) | |
Adjusted model IIb | 1 | 1.19(0.77–1.82) | 1.23(0.89–1.68) | 1.46(1.07–1.98) | |
LBW | |||||
N (%) | 167(2.5) | 94(2.0) | 10(2.7) | 32(4.3) | 31(4.6) |
Adjusted model I* | 1 | 1.44(0.74–2.80) | 2.30(1.52–3.45) | 2.44(1.60–3.70) | |
Adjusted model IIb | 1 | 1.39(0.61–3.16) | 1.15(0.65–2.01) | 2.10(1.25–3.51) | |
WAZ < -1 at 12 months of age (n = 3181) | |||||
N (%) | 99(3.1) | 67(2.9) | 3(1.7) | 13(3.6) | 16(5.1) |
Adjusted model I* | 1 | 0.61(0.19–1.97) | 1.27(0.69–2.34) | 1.84(1.05–3.24) | |
Adjusted model IIc | 1 | 0.61(0.19–2.00) | 1.11(0.60–2.13) | 1.79(1.01–3.19) |