Risk factors for uterine rupture and neonatal consequences of uterine rupture: a population‐based study of successive pregnancies in Sweden

Abstract

Objective Uterine rupture is a rare but a catastrophic event. The aim of the present study was to explore the risk factors for uterine rupture and associated neonatal morbidity and mortality among a cohort of Swedish women attempting vaginal birth in their second delivery.Design Population-based cohort study.Setting Sweden. Methods Swedish population-based registers were used to obtain information concerning demographics, pregnancy and birth characteristics, and neonatal outcomes. Logistic regression was used to analyse potential risk factors for uterine rupture and risk of neonatal mortality associated with uterine rupture. Odds ratios were used to estimate relative risks using 95% CI.Main outcome measure Uterine rupture and neonatal mortality in the second pregnancy.Results Compared with women who delivered vaginally in their first birth, women who underwent a caesarean delivery were, during their second delivery, at increased risk of uterine rupture (adjusted OR 41.79; 95% CI 29.73-57.00). Induction of labour, high ( ‡4000 g) birthweight, postterm ( ‡42 weeks) births, high ( ‡35 years) maternal age, and short (£164 cm) maternal stature were also associated with increased risk of uterine rupture. Uterine rupture was associated with a substantially increased risk in neonatal mortality (adjusted OR 65.62; 95% CI 32.60-132.08). ConclusionThe risk of uterine rupture in subsequent deliveries is not only markedly increased among women with a previous caesarean delivery but also influenced by induction of labour, birthweight, gestational age, and maternal characteristics.Keywords Caesarean section, cohort study, infant mortality, Sweden, uterine rupture, vaginal birth after caesarean.Please cite this paper as: Kaczmarczyk M, Sparén P, Terry P, Cnattingius S. Risk factors for uterine rupture and neonatal consequences of uterine rupture: a population-based study of successive pregnancies in Sweden.

Risk factors of uterine rupture with a special interest to uterine fundal pressure

“…This finding may be related to the thorough assessment of a single center-database. Rupture in patients with previous uterine surgery was seen in 2.04% (15 of 737), compared to 0.9%-1% in other large retrospective studies [3,20]. Also in the subgroup of women with an unscarred uterus, in our collective a higher incidence of uterine rupture was observed as compared to the published incidence in other studies (0.067% vs. 0.02%-0.006%) [3][4][5].…”

“…The overall incidence of uterine rupture was 0.14% (28 of 20,152) which is higher than the median incidence of uterine rupture based on studies in high-income countries (0.09%) [3]. This finding may be related to the thorough assessment of a single center-database.…”

“…Several risk factors have been identified, the most important being a uterine scar, mostly from previous cesarean section [1][2][3]. The median incidence of uterine rupture based on studies in high-income countries is around 0.09% [3].…”

“…Several risk factors have been identified, the most important being a uterine scar, mostly from previous cesarean section [1][2][3]. The median incidence of uterine rupture based on studies in high-income countries is around 0.09% [3]. After previous cesarean section, the incidence varies between 0.4% and 0.9% [3,5] whereas in women without prior uterine surgery the incidence of uterine rupture is about 0.006%-0.02% [4,5].…”

“…The median incidence of uterine rupture based on studies in high-income countries is around 0.09% [3]. After previous cesarean section, the incidence varies between 0.4% and 0.9% [3,5] whereas in women without prior uterine surgery the incidence of uterine rupture is about 0.006%-0.02% [4,5]. In addition to previous cesarean section, postulated risk factors for uterine rupture are induction of labor, maternal age, multiparity, gestational age at delivery, vacuum-assisted birth, fetal birth weight, short inter pregnancy interval, prolonged second stage of labor, abnormal placentation, and uterine fundal pressure (UFP) [2,[6][7][8][9][10][11][12][13][14][15].…”