Table 5. Cesarean section and rate of subsequent stillbirth, miscarriage, or ectopic pregnancy—3-y follow-up.
| Outcome by Mode of Deliverya | Crude Model HR (95% CI) | Adjusted HR (95% CI) | ||
| Model 1b | Model 2c | Model 3d | ||
| Stillbirth ( n = 916 events) | ||||
| Spontaneous vaginal (n = 632) | Ref | Ref | Ref | Ref |
| Operative vaginal (n = 83) | 0.97 (0.77, 1.22) | 0.96 (0.76, 1.21) | 0.94 (0.74, 1.19) | 0.96 (0.76, 1.22) |
| All cesarean sectionse (n = 201) | 1.26 (1.08, 1.48) | 1.30 (1.11, 1.53) | 1.25 (1.06, 1.48) | 1.18 (1.00, 1.40) |
| Emergency cesarean (n = 148) | 1.30 (1.09, 1.56) | 1.34 (1.12, 1.61) | 1.29 (1.07, 1.56) | 1.22 (1.01, 1.47) |
| Elective cesarean* (n = 53) | 1.17 (0.88, 1.55) | 1.20 (0.91, 1.60) | 1.15 (0.86, 1.54) | 1.08 (0.81, 1.45) |
| Miscarriage ( n = 45,321 events) | ||||
| Spontaneous vaginal (n = 32,883) | Ref | Ref | Ref | Ref |
| Operative vaginal (n = 4,780) | 1.11 (1.07, 1.14) | 1.02 (0.99, 1.05) | 1.01 (0.98, 1.04) | 1.09 (1.06, 1.13) |
| All cesarean sectionse (n = 7,554) | 0.94 (0.91, 0.96) | 0.92 (0.90, 0.94) | 0.95 (0.93, 0.98) | 0.95 (0.93, 0.98) |
| Emergency cesarean (n = 5,519) | 0.95 (0.92, 0.98) | 0.94 (0.91, 0.97) | 0.96 (0.93, 0.99) | 0.96 (0.93, 0.99) |
| Elective cesarean (n = 2,035) | 0.91 (0.87, 0.95) | 0.87 (0.84, 0.91) | 0.93 (0.89, 0.97) | 0.93 (0.89, 0.97) |
| Maternally requested cesarean (n = 104) | 0.68 (0.56, 0.82) | 0.70 (0.58, 0.85) | 0.73 (0.60, 0.88) | 0.78 (0.64, 0.95) |
| Ectopic pregnancy ( n = 6,278 events) | ||||
| Spontaneous vaginal (n = 4,467) | Ref | Ref | Ref | Ref |
| Operative vaginal (n = 596) | 1.01 (0.93, 1.10) | 1.02 (0.93, 1.11) | 1.01 (0.93, 1.11) | 1.06 (0.97, 1.15) |
| All cesarean sectionse (n = 1,215) | 1.10 (1.03, 1.17) | 1.08 (1.01, 1.15) | 1.08 (1.02, 1.16) | 1.08 (1.01, 1.16) |
| Emergency cesarean (n = 893) | 1.13 (1.05, 1.21) | 1.11 (1.03, 1.20) | 1.12 (1.04, 1.20) | 1.12 (1.04, 1.21) |
| Elective cesarean* (n = 322) | 1.02 (0.91, 1.14) | 0.99 (0.88, 1.11) | 1.00 (0.89, 1.12) | 0.99 (0.88, 1.11) |
Women were followed up for a maximum of 3 y from the date of the first live birth until the subsequent event to test for informative censoring due to live birth. Cohort 1982–2010 (n = 832,996 women).
Number of events of the outcome of interest for each mode of delivery in parentheses.
Model 1: adjusted for maternal age; maternal origin; previous stillbirth, miscarriage, or ectopic pregnancy; mother's marital status; birth year; and measures of socio-economic status including mother's educational attainment and mother's and father's gross income.
Model 2: adjusted for Model 1 plus medical complications in the first live birth including delivery type (singleton versus twins or more), diabetes, gestational diabetes, placental abruption, placenta praevia, and hypertensive disorders (including eclampsia and preeclampsia).
Model 3: adjusted for Model 2 plus gestational age and birth weight.
*Where the number of events was less than ten for maternally requested cesarean, these were combined with the elective cesarean group for analyses.