乌鸦传媒

For women with a previous cesarean section, an intervention aimed at supporting decision making reduced perinatal and maternal morbidity compared with usual care, the Canadian PRISMA trial found.

Those in the intervention group saw a significant reduction in perinatal morbidity compared with the control group (adjusted OR 0.72, 95% CI 0.52-0.99, P=0.042), according to Nils Chaillet, PhD, of CHU de Québec Research Center and Laval University in Quebec, Canada, and colleagues .

The intervention also significantly reduced major maternal morbidity compared to the control group (aOR 0.54, 95% CI 0.33-0.89, P=0.016), and rates of minor perinatal or maternal morbidity, caesarean delivery, or uterine rupture were not significantly different between groups, they found.

"A multifaceted intervention supporting women in their choice of mode of delivery and promoting best practices resulted in a significant reduction in rates of major perinatal and maternal morbidity, without an increase in the rate of caesarean or uterine rupture," the researchers wrote.

Whether or not to attempt vaginal delivery following a previous cesarean delivery can be a difficult choice for women when they get pregnant again. Planning another caesarean delivery may be associated with a higher risk of maternal complications than a vaginal delivery, though attempting vaginal delivery is linked with greater risks of uterine rupture and perinatal complications.

Researchers wanted to assess if an intervention that involved professional training on best practices, a decision aid tool, and an estimation of the probability of vaginal delivery and an ultrasound estimation of the risk of uterine rupture -- all intended to support a woman's decision-making on the best mode of delivery -- could reduce risks. Authors noted the trial is the first study to combine these tools in a "single multifaceted intervention."

, Leandro De Oliveira, MD, PhD, of Botucatu São Paulo State University in Brazil, and co-authors noted that surgical caesarean deliveries can result in major complications and death, especially in facilities with fewer resources, but wrote that PRISMA takes doctors "one further step towards an informed, risk-­stratified approach to identification of higher­-risk pregnancies."

Farah Amro, MD, assistant professor and maternal-fetal medicine physician with UTHealth Houston in Texas, told 乌鸦传媒 that the study was well done, but had different baseline demographics than America; rates of obesity were much lower and race and ethnicity were not reported. However, she said the results emphasize "to us as physicians the utility of a shared-decision making model, and that beyond patient satisfaction and patient empowerment, it also may translate clinically into a decrease in patient morbidity."

The PRISMA cluster-randomized controlled trial took place from April 1, 2016 to Dec 13, 2019 at 40 hospitals in Quebec. Eligible participants were women who had one previous cesarean delivery and a singleton gestation delivered at participating hospitals. Newborns needed to have a gestational age of at least 24 weeks and weigh at least 500 g at delivery. The 21,281 eligible women were split between intervention (10,514; mean age 32.3) and control (10,767; mean age 33.2). No one was lost to follow-up.

Block randomization was stratified by level of care: community (4), regional (28), or tertiary hospital (8). Hospitals had to have at least 300 deliveries a year to participate. There was a 1-year baseline period, where hospitals were randomized 1:1 to intervention or control, followed by 5 to 8 months of implementation, and then a 2-year intervention period.

The primary outcome was a composite risk of perinatal complications, which included death (excluding lethal congenital abnormalities), Apgar score, major trauma, major respiratory morbidity, and proven neonatal sepsis or infection. Secondary outcomes included composite risks of both minor and major maternal complications, as well as minor perinatal complications, planned and unplanned caesarian delivery, and vaginal and assisted vaginal delivery.

Authors note several limitations, including that the number of deliveries varied across hospitals due to hospital-blocked randomization and that the control group's rate of perinatal morbidity increased over time, possibly due to a 2017 policy change. Also, the trial wasn't designed to detect differences across race and ethnicity, and because the intervention was multifaceted, exactly which components were most responsible for the results could not be determined.

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