American journal of obstetrics and gynecology · 2026
Antenatal oxytocin and respiratory adaptation after prelabor cesarean delivery in late-preterm lambs: a randomized factorial experiment.
СтатьяНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Leostic Anne, Rodriguez Yoann, Richard Christophe, Berveiller Paul, Mauffre Vincent, Motte-Signoret Emmanuelle
Аннотация
BACKGROUND: Late-preterm infants born at 34-36+6 weeks' gestation and delivered by elective cesarean section before the onset of labor are at high risk of neonatal respiratory distress, in which impaired fetal lung fluid clearance plays a major role. No preventive strategy specifically targeting this mechanism is currently available.
OBJECTIVE: To evaluate whether antenatal exposure to oxytocin, alone or combined with dexamethasone, improves early neonatal respiratory adaptation in a late-preterm lamb model delivered by cesarean section.
STUDY DESIGN: In this randomized 2 × 2 factorial study with blinded neonatal assessment, 23 pregnant ewes were independently assigned to dexamethasone or placebo 3 days before delivery and to continuous intravenous oxytocin or placebo starting 5 hours before cesarean delivery at 140 days of gestation. The primary outcome was a composite adverse perinatal outcome including perinatal death, neonatal resuscitation or intubation, a 5-minute modified Apgar score ≤4, or acidosis at 1 hour of life. The secondary outcomes included clinical signs, ultrasound, and biological markers of respiratory distress. Analyses were performed according to the intention-to-treat principle using mixed-effects models with ewe as a random intercept to account for within-litter clustering.
RESULTS: A total of 54 late-preterm lambs were delivered from 23 ewes. Among the 49 lambs with evaluable primary outcome data, the primary composite outcome was observed in 11/12 lambs (91.7%) in the placebo group, 8/15 (53.3%) in the oxytocin group, 5/10 (50.0%) in the dexamethasone group, and 0/12 lambs (0%) in the dexamethasone-oxytocin group. After accounting for within-litter clustering, combined dexamethasone and oxytocin exposure was associated with a lower risk for requiring resuscitation (adjusted RR, 0.01; 95% CI, <0.01-0.40) compared with placebo-placebo. In factorial analyses, dexamethasone exposure was associated with reduced intubation (β, -3.40; 95% CI, -6.67 to -0.14) and low 5-minute Apgar scores (β, -3.70; 95% CI, -6.8 to -0.6), whereas no statistically significant main effect of oxytocin or oxytocin-by-dexamethasone interaction was identified. Similar patterns were observed for resuscitation, intubation, modified Apgar and Silverman scores, and lung ultrasound findings.
CONCLUSION: In this late-preterm lamb model, antenatal oxytocin exposure was associated with improved neonatal respiratory adaptation after cesarean delivery, with the most favorable outcomes observed when combined with dexamethasone. These findings support further investigation of labor-related hormonal pathways in perinatal respiratory transition.
OBJECTIVE: To evaluate whether antenatal exposure to oxytocin, alone or combined with dexamethasone, improves early neonatal respiratory adaptation in a late-preterm lamb model delivered by cesarean section.
STUDY DESIGN: In this randomized 2 × 2 factorial study with blinded neonatal assessment, 23 pregnant ewes were independently assigned to dexamethasone or placebo 3 days before delivery and to continuous intravenous oxytocin or placebo starting 5 hours before cesarean delivery at 140 days of gestation. The primary outcome was a composite adverse perinatal outcome including perinatal death, neonatal resuscitation or intubation, a 5-minute modified Apgar score ≤4, or acidosis at 1 hour of life. The secondary outcomes included clinical signs, ultrasound, and biological markers of respiratory distress. Analyses were performed according to the intention-to-treat principle using mixed-effects models with ewe as a random intercept to account for within-litter clustering.
RESULTS: A total of 54 late-preterm lambs were delivered from 23 ewes. Among the 49 lambs with evaluable primary outcome data, the primary composite outcome was observed in 11/12 lambs (91.7%) in the placebo group, 8/15 (53.3%) in the oxytocin group, 5/10 (50.0%) in the dexamethasone group, and 0/12 lambs (0%) in the dexamethasone-oxytocin group. After accounting for within-litter clustering, combined dexamethasone and oxytocin exposure was associated with a lower risk for requiring resuscitation (adjusted RR, 0.01; 95% CI, <0.01-0.40) compared with placebo-placebo. In factorial analyses, dexamethasone exposure was associated with reduced intubation (β, -3.40; 95% CI, -6.67 to -0.14) and low 5-minute Apgar scores (β, -3.70; 95% CI, -6.8 to -0.6), whereas no statistically significant main effect of oxytocin or oxytocin-by-dexamethasone interaction was identified. Similar patterns were observed for resuscitation, intubation, modified Apgar and Silverman scores, and lung ultrasound findings.
CONCLUSION: In this late-preterm lamb model, antenatal oxytocin exposure was associated with improved neonatal respiratory adaptation after cesarean delivery, with the most favorable outcomes observed when combined with dexamethasone. These findings support further investigation of labor-related hormonal pathways in perinatal respiratory transition.