RESUMEN
BACKGROUND: Premature rupture of membranes (PROM) is a complication affecting 7-12% of pregnancies in which fetal chorioamniotic membranes rupture before labour begins. Preterm PROM (PPROM) (ie <37 weeks gestation) precedes one-third of preterm births, exposing the fetus to increased morbidity from placental abruption, respiratory distress syndrome and sepsis. AIM: To analyse trends in the incidence and mode of birth in preterm and term PROM in Victoria, Australia between 2009 and 2017. MATERIALS AND METHODS: This retrospective population-based cohort study included all singleton pregnancies from 2009 to 2017. We examined women with PROM (both <37 weeks (PPROM) and at term). Management was assessed in three categories: (a) expectant management; (b) induction of labour (IOL); and (c) elective caesarean section (elCS). A multinomial logistic regression model was used to adjust for confounders influencing the choice of management. RESULTS: Of 636 590 singleton pregnancies, 52 669 (8.3%) births with PROM at term (42 439; 6.7%) or PPROM (10 230; 1.6%) were identified. Of these, the majority were managed expectantly (n = 22 726; 43.1%), or with IOL (25 931; 49.2%). While elCS represented only 7.6% of these cases (n = 4012), its use rose consistently from 2009 to 2017 for PROM at term and PPROM alike. For women with PPROM at 34-36 weeks the odds of elCS increased by 5% annually (adjusted odds ratio (aOR) 1.05; 95% CI 1.02-1.08) and 2% for IOL (aOR 1.02; 95% CI 1.00-1.05) vs expectant management. CONCLUSIONS: The use of elCS and IOL in PPROM is rising in Victoria, particularly between 34 and 36 completed weeks of pregnancy. Research is needed to determine the drivers for this increase.
RESUMEN
This study aimed to investigate the reproductive impact of a third- or fourth-degree tear in primigravid women. A retrospective population-based cohort study was conducted using data from Scottish Morbidity Records (SMR02). Primigravid women with a vaginal birth in Scotland from 1997 until 2010 were included. Exposure was third- or fourth-degree tear in the first pregnancy. The second pregnancy rate, interpregnancy interval and third- or fourth-degree tear in a second pregnancy were the primary outcomes. A nested case-control study was used to determine factors associated with repeat third- or fourth-degree tears in a second vaginal birth. Cox regression analysis and logistic regression were used to look for associations. Initial third- or fourth-degree tear occurred in 2.8% women (5174/182445). The percentage of third- or fourth-degree tears in first vaginal births increased from 1% in 1997 to 4.9% in 2010. There was no difference in having a second pregnancy (adjusted Odds Ratio (aOR) 0.98 (99%CI 0.89-1.09)) or the median interpregnancy interval to second pregnancy (adjusted Hazard Ratio (aHR) 1.01 (99%CI 0.95-1.08)) after an initial third- or fourth-degree tear. Women were over four times more likely to have a repeat injury in a subsequent vaginal birth (n = 149/333, aOR 4.68 (99% 3.52-6.23)) and were significantly more likely to have an elective caesarean section in their second pregnancy (n = 887/3333, 26.6%; 12.75 (11.29-14.40)). Increased maternal age and birthweight ≥4500g were risk factors for repeat injury. Third- and fourth-degree tears are increasing in Scotland. Women do not delay or avoid childbirth after initial third- or fourth-degree tear. However, women are more likely to have a repeat third- or fourth-degree tear or an elective caesarean section in the second pregnancy. Strategies to prevent third- or fourth-degree tears are needed.