Table 1: Potential risk factors for surgical site infection that were examined, to determine inclusion in multivariable model in univariate analyses.
| Category | Factors not associated with infection (p ≥ 0.10) | Factors associated with infection (p < 0.10) |
|---|---|---|
| Institution-related | - | No. of cesarean deliveries in delivery hospital (< 130, 130-949, 950-1249, ≥ 1250) |
| Area-level | Maternal residence (urban, rural) | Region of maternal residence (A, B, C, D) Neighbourhood-level income quintile (1, 2, ≥ 3) |
| Maternal demographic characteristics | - | Maternal age (< 25 yr, 25-34 yr, ≥ 35 yr) Prepregnancy weight (< 53.0 kg, 53.0-66.9 kg, 67.0-76.9 kg, 77.0-86.9 kg, 87.0-97.9 kg, ≥ 98.0 kg, missing) Marital status (married or common-law, other, missing) Smoking during pregnancy (no, yes) Alcohol or drug abuse during pregnancy (no, yes) |
| Maternal medical conditions | Maternal influenza immunization in pregnancy (no, yes) | Nonobstetric preexisting health condition affecting pregnancy (no, yes) Hypertension (no, preexisting, gestational or unspecified, preeclampsia) Diabetes (no, preexisting, gestational) Anemia during pregnancy (no, yes) Depression (no, yes) Anticoagulation therapy during pregnancy (no, yes) |
| Pregnancy history | Surgical site infection after previous cesarean delivery (no, yes) | Parity (primiparous, multiparous) Mode of delivery in last pregnancy (none, vaginal, cesarean Previous cesarean delivery (0, 1, ≥ 2) |
| Pregnancy characteristics | - | Weight gain during pregnancy (< 10.0 kg, 10.0-19.9 kg, 20.0-29.9 kg, ≥ 30.0 kg, missing) Chorioamnionitis (no, yes) Diagnostic and/or therapeutic procedure(s) performed in woman (no, yes) Steroid use ≥ 48 h before delivery for fetal lung maturity (no, yes) |
| Labour | Cervical dilation at last examination before cesarean delivery (0 cm, 1-3 cm, 4-10 cm) Time between rupture of membranes to delivery (≤ 1 h, 2-11 h, ≥ 12 h) Stage of labour before cesarean delivery (none, first, second) Spontaneous rupture of membranes (yes, no) |
|
| Delivery | Season of delivery (December-February, March-May, June-August, October-November) Type of cesarean delivery (low segment transverse, other) Instrumentation use (no, forceps/vacuum) General anesthesia during labour and/or delivery (no, yes) Other procedure(s) performed during cesarean delivery (no, yes) |
Length of antepartum stay (< 24 h, 24-49 h, ≥ 50 h) Year of delivery (1997-2000, 2001-2004, 2005-2008, 2009-2012) Delivery on weekend (no, yes) Primary indication for cesarean delivery (breech presentation, dystocia, fetal distress, other, previous cesarean delivery) Regional anesthesia during labour and/or delivery (no, yes) Antibiotic therapy during labour and delivery (yes, no) Maternal blood transfusion (no, yes) |
| Fetal and neonatal | Presentation at delivery (vertex, other, missing) No. of fetuses (1, ≥ 2) Diagnostic and/or therapeutic procedure(s) performed in fetus (no, yes) |
Infant birth weight (< 2500 g, 2500-3999 g, ≥ 4000 g) Apgar score at 5 min (< 7, ≥ 7) Gestational age (< 37 wk, 37 wk to 39 wk + 6 d, ≥ 40 wk) Breastfeeding at discharge (yes, no) |