Mar 15, 2007

Research contradicts the Term Breech Trial (TBT)

A study of 13,000 breech and headfirst births at a Parisian Hospital resulted in a surprisingly high rate of vaginal breech delivery (79%). This is of the highest rates recorded in the literature. The most surprising finding was the absence of significant differences in neonatal morbidity between breech and vertex babies regardless of mode of delivery.

Additionally, there were no significant differences in neonatal morbidity between breech babies delivered vaginally and those delivered by planned cesarean. The use of strict obstetric protocols for breech presentation---including pelvimetry, continuous cervical dilation, very limited use of oxytocin or induction, and specific extraction techniques were held responsible for the excellent neonatal outcomes.

Among both headfirst and breech babies, those delivered by planned cesarean were MORE likely to be intubated than those delivered vaginally. Vertex babies delivered by cesarean were eight times more likely to be intubated and six times more likely to be admitted to the NICU than those born vaginally. See Pubmed Abstract.

These latter findings confirm recent studies showing the link between cesarean delivery and increased risk for respiratory distress syndrome in near term infants.  
A 2006 study looking at over 8,000 breech births in France and Belgium concluded that there were no significant differences between planned vaginal and planned cesarean deliveries. The study used similar outcome measures as the TBT, but far stricter criteria for obstetric management. Thus, the outcomes for vaginal deliveries far surpassed those of the TBT and several similar studies. This study showed vaginal breech delivery to be as safe as cesarean delivery, as long as careful selection criteria are followed. The TBT, by contrast, did far less to ensure the safety of the vaginal deliveries it interrogated.

Unlike the TBT, all babies in the vaginal arm were in frank breech position, with no hyper-extension (the star-gazing position). There were no infants with excessively high or low birthweights and all were subjected to continuous electronic fetal heart-rate monitoring. Moreover, pelvimetry was used for over 80% of the candidates in this study, unlike the TBT where only 10% of all women received any pelvic measurement. In this study, roughly 75% of all breech babies were delivered by cesarean. Pubmed Abstract here.

A study of over 600 births in Ireland concluded that vaginal delivery is as safe as cesarean, as long as strict protocol were followed including: appropriate fetal weight (between 2500 -3800 gms), sufficient amniotic fluid, normal fetal morphology, absence of hyperextension of the head, and absence of complete or frank breech presentation. There was no induction nor augmentation of labor other than amniotomy, and women were supposed to dilate 1 cm per hour and limited to no more than one hour of pushing. All women were attended by an experienced obstetrician, using Løvset's maneuver to deliver shoulders and the Mariceau-Smellie-Veit maneuver, if required. The authors state that both obstetric protocols and the avoidance of oxytocin for induction/augmentation are responsible for the favorable outcomes. Pubmed Abstract here.

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