Table 3.
Meta-regression analysis for the impact of potential confounding factors
| Maternal Age | BMI | Gravidity | Parity | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Coef(95%CI) | t | P | Coef (95%CI) | t | P | Coef (95%CI) | t | P | Coef (95%CI) | t | P | |
| Preterm birth | 21.05(5.34, 36.76) | 2.87 | 0.01 | 5.31(-7.02, 17.65) | 0.92 | 0.37 | -9.69(-26.05, 6.68) | -1.27 | 0.23 | -0.59(-15.90,14.72) | -0.08 | 0.94 |
| Cesarean delivery | 1.41(-0.36, 3.17) | 1.74 | 0.11 | 0.35(-0.66, 1.36) | 0.75 | 0.47 | -0.34(-1.02, 1.34) | -0.44 | 0.67 | -0.11(-1.59, 1.37) | -0.16 | 0.88 |
| Malposition | 15.01(-1.21,31.24) | 2.06 | 0.07 | 3.30(-11.80,18.39) | 0.49 | 0.64 | -6.69(-13.82,0.45) | -2.09 | 0.06 | - | - | - |
| Fetal distress | 8.75(-2.89,20.38) | 1.64 | 0.13 | - | - | - | -3.96(-9.07,1.15) | -1.69 | 0.12 | - | - | - |
| PPROM | -1.95(-8.84,4.95) | -0.65 | 0.53 | 0.59(-3.28,4.47) | 0.35 | 0.73 | -0.98(-7.14,5.18) | -0.37 | 0.72 | 3.34(-2.01,8.70) | 1.44 | 0.19 |
| Placenta previa | 0.10(-5.96,6.17) | 0.04 | 0.97 | 0.61(-3.89,5.11) | 0.31 | 0.77 | 0.02(-5.97,6.02) | 0.01 | 0.99 | -0.74(-6.31,4.84) | -0.30 | 0.77 |
| Placental abruption | 4.42(-1.60,10.43) | 1.66 | 0.13 | 1.53(-1.36,4.44) | 1.20 | 0.26 | -2.49(-7.69,2.72) | -1.08 | 0.31 | 0.18(-4.51,4.87) | 0.09 | 0.93 |
| PPH | 36.25(-7.11,89.62) | 1.61 | 0.15 | 2.19(-27.03,31.41) | 0.18 | 0.86 | -12.12(-29.0,4.77) | -1.70 | 0.13 | - | - | - |
| Miscarriage | 6.33(-2.55,15.20) | 1.59 | 0.14 | - | - | - | -3.22(-7.34,0.89) | -1.74 | 0.11 | - | - | - |
| IFD | -0.67(-4.23,2.89) | -0.52 | 0.63 | 3.02(0.34,5.70) | 3.13 | 0.04 | - | - | - | 0.76(-1.13,2.65) | 1.12 | 0.33 |
| Smoking | Diabetes | Hypertension | ||||||||||
| Coef (95%CI) | t | P | Coef (95%CI) | t | P | Coef (95%CI) | t | P | ||||
| Preterm birth | 4.27(-6.20, 14.75) | 0.87 | 0.40 | -3.48(-15.95, 8.99) | -0.60 | 0.56 | 5.22(-2.04, 12.48) | 1.50 | 0.15 | |||
| Cesarean delivery | 0.12(-0.93, 1.17) | 0.25 | 0.81 | -0.15(-1.29, 1.00) | -0.28 | 0.79 | -0.13(-3.44, 3.17) | -0.09 | 0.93 | |||
| Malposition | -2.56(-15.54,10.41) | -0.44 | 0.67 | 0.97(-11.26,13.19) | 0.18 | 0.86 | -10.13(-54.77,34.50) | -0.51 | 0.62 | |||
| Fetal distress | -2.25(-10.77,6.27) | -0.58 | 0.57 | 1.55(-7.25.10.35) | 0.38 | 0.71 | - | - | - | |||
| PPROM | -2.09(-5.67,1.50) | -1.34 | 0.22 | -1.31(-4.95,2.34) | -0.83 | 0.43 | - | - | - | |||
| Placenta previa | 2.96(-2.59,8.51) | 1.20 | 0.26 | -1.39(-7.72,4.94) | -0.5 | 0.63 | - | - | - | |||
| Placental abruption | - | - | - | - | - | - | - | - | - | |||
| PPH | -5.49(-48.49,37.52) | -0.30 | 0.77 | 2.96(-36.59,42.53) | 0.18 | 0.86 | 2.96(-36.60,42.53) | 0.18 | 0.86 | |||
| Miscarriage | 0.08(-6.62,6.78) | 0.03 | 0.98 | -0.09(-6.79,6.61) | -0.03 | 0.98 | - | - | - | |||
| IFD | -0.50(-2.96,1.96) | -0.57 | 0.60 | -3.27(-5.58,0.96) | 1.15 | 0.32 | - | - | - | |||
Abbreviation PPROM, Preterm premature rupture of membranes; PPH, Postpartum hemorrhage; IFD, Intrauterine fetal demise; Coef, Coefficient; 95%CI: 95% confidence interval; BMI, body mass index