Skip to main content

Advertisement

Table 5 Population attributable fractions for maternal systemic/localized comorbidity and preterm birth according to clinical subtype and gestational age*

From: Association between maternal comorbidity and preterm birth by severity and clinical subtype: retrospective cohort study

  Medically indicated PPROM* Spontaneous
  < 28 wk 28-31 wk 32-36 wk < 28 wk 28-31 wk 32-36 wk < 28 wk 28-31 wk 32-36 wk
Systemic comorbidity          
   Hypertension          
Preeclampsia/eclampsia 21.6 38.0 21.9 -1.2 -0.7 -0.2 -1.2 -0.6 0.2
Pre-existing 0.8 1.1 1.6 0 0.1 0.1 0 0 -0.1
Gestational 0.2 1.8 1.8 -4.5 -0.8 -0.4 -2.4 -4.3 -0.3
   Cardiovascular disease 0.4 0.8 0.6 0.1 0.5 0.1 0.2 0.3 0.02
   Diabetes          
Pre-existing 0.3 2.7 3.4 0.1 3.0 1.2 -0.1 1.4 0.5
Gestational -1.9 0.6 2.6 -1.5 1.0 1.8 -3.0 -0.8 1.1
   Edema/renal disease 1.6 2.9 1.7 0.1 0.2 0.02 0.2 -0.03 0.03
   Genitourinary infection 1.7 3.7 1.9 1.7 3.6 0.5 0.7 -0.02 -0.05
   General infection 1.8 1.4 1.4 1.6 2.1 0.4 0.9 1.2 0.3
   Thyroid disease 1.4 1.0 0.9 0.6 0.8 0.3 0.1 0.5 0.1
   Anemia 11.9 14.8 5.9 6.7 6.6 -1.1 3.3 -0.1 -2.9
   Drug dependence 0.03 0.9 0.5 0.8 0.9 0.5 0.7 1.1 0.7
   Mental disorders 1.7 0.9 0.8 0.9 1.8 0.5 1.0 0.8 0.4
Localized comorbidity          
   Hemorrhage          
Placental abruption 23.5 21.0 9.8 14.1 17.9 2.4 25.2 22.9 4.5
Placenta previa 3.3 5.9 6.6 2.2 1.2 0.3 0.5 0.4 -0.1
   Chorioamnionitis 10.5 2.0 -0.3 31.4 30.7 3.8 25.1 11.7 0.04
   Amniotic sac          
Polyhydramnios 1.3 2.3 1.5 0.3 0.8 0.2 0.7 1.8 0.4
Oligohydramnios 8.7 10.3 7.0 8.2 10.2 1.2 1.6 0.6 -0.2
   Cervical incompetence 7.2 1.4 0.7 8.1 3.5 0.5 14.6 3.1 0.6
   Structural abnormality 41.9 36.0 17.3 14.9 22.9 7.0 11.8 6.2 -1.2
   Previous cesarean delivery 1.4 2.3 8.7 0.4 -1.3 -2.3 -5.7 -4.7 -5.4
   Fetal anomaly 6.5 0.7 0.5 0.1 0.3 0.1 5.7 0.3 0.1
  1. * Preterm premature rupture of membranes
  2. † Spontaneous preterm labour before 37 gestational weeks with intact membranes