Outcome | n (%) with outcome | ||||
38-IOL group (n=937) | 39-Exp group (n=1276) | Crude RR (95% CI) | Adjusted RR* (95% CI) | Adjusted RR† (95% CI) | |
Maternal | |||||
Cesarean delivery | 269 (28.7) | 333 (26.1) | 1.10 (0.96 to 1.26) | 1.07 (0.94 to 1.22) | 1.02 (0.90 to 1.16) |
Instrumental delivery | 105 (11.2) | 130 (10.2) | 1.10 (0.86 to 1.40) | 1.25 (0.98 to 1.61) | 1.29 (1.00 to 1.66) |
Shoulder dystocia | 57 (6.1) | 52 (4.1) | 1.49 (1.03 to 2.15) | 1.35 (0.92 to 1.97) | 1.05 (0.71 to 1.55) |
Neonatal | |||||
Neonatal composite morbidity‡ | 449 (47.9) | 401 (31.4) | 1.52 (1.37 to 1.69) | 1.50 (1.34 to 1.67) | 1.42 (1.27 to 1.59) |
NICU admission | 259 (27.6) | 215 (16.8) | 1.64 (1.40 to 1.93) | 1.61 (1.36 to 1.90) | 1.50 (1.26 to 1.77) |
Jaundice requiring phototherapy | 116 (12.4) | 79 (6.2) | 2.00 (1.52 to 2.63) | 1.93 (1.46 to 2.57) | 1.76 (1.32 to 2.33) |
Hypoglycemia | 256 (27.3) | 187 (14.7) | 1.86 (1.57 to 2.21) | 1.74 (1.46 to 2.07) | 1.61 (1.35 to 1.93) |
Respiratory morbidity§ | 114 (12.2) | 135 (10.6) | 1.15 (0.91 to 1.45) | 1.11 (0.87 to 1.42) | 1.02 (0.80 to 1.31) |
Cohort definition: Women who had a singleton birth who met the inclusion criteria.
Data sources: Better Outcomes Registry and Network Ontario (2012–2017), Canadian Institute of Health Information-Discharge Abstract Database (CIHI-DAD; 2012–2015).
*Adjusted for maternal age, pre-pregnancy body mass index (BMI), nulliparity, and diabetes type.
†Adjusted for maternal age, pre-pregnancy BMI, nulliparity, diabetes type and large for gestational age (LGA) >90th percentile.
‡Defined as the presence of any of the following: perinatal mortality (stillbirth or neonatal death), 5 min Apgar score <7, admission to the neonatal intensive care unit (NICU), hypoglycemia, jaundice requiring phototherapy, or neonatal respiratory morbidity.
§Refers to respiratory distress syndrome, transient tachypnea of the newborn infant, or need for respiratory support.
Exp, expectant management; IOL, induction of labor; RR, relative risk.