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Transactions of the Twenty-Fourth Annual Meeting of the Society for Maternal-Fetal Medicine| Volume 191, ISSUE 3, P872-873, September 01, 2004

The Term Breech Trial

      Readers of the American Journal will be interested in 2 papers by Hannah et al that present infant and maternal outcome data at 2 years' postpartum from women enrolled in the Term Breech Trial. Data collected in this study have always been analyzed by the “intent to treat” principle, in which outcomes are compared according to the group assignment (planned cesarean or planned vaginal delivery), rather than the actual mode of delivery. This is the optimal method for analysis of primary outcome data from randomized trials because it reduces the opportunity for bias. The initial primary results for both infants and mothers were reported in 2000 for 2088 women enrolled at 121 sites.
      • Hannah M.E.
      • Hannah W.J.
      • Hewson S.A.
      • Hodnett E.D.
      • Saigal S.
      • et al.
      Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Term Breech Trial Collaborative Group.
      Perinatal mortality, neonatal mortality, and serious neonatal morbidity were significantly less frequent for infants born to women in the planned cesarean group than in the planned vaginal delivery group (1.6% vs 5.0%). Maternal mortality and serious maternal morbidity did not differ. In 2002, the authors reported maternal morbidity outcomes at 3 months' postpartum for 1596 women enrolled at 110 sites.
      • Hannah M.E.
      • Hannah W.J.
      • Hodnett E.D.
      • Chalmers B.
      • Kung R.
      • Willan A.
      • et al.
      Term Breech Trial 3-Month Follow-up Collaborative Group, outcomes at 3 months after planned cesarean vs planned vaginal delivery for breech presentation at term: the international randomized Term Breech Trial.
      Women in the planned cesarean group were less likely (4.5%) to report urinary incontinence than those in the planned vaginal delivery group (7.3%). At the 2004 SMFM, Hannah et al
      • Whyte H.
      • Hannah M.
      • Saigal S.
      Outcomes of children at 2 years of age in the term breech trial.
      reported the infant outcomes at 2 years of age. The lead article in the SMFM section of this issue of the American Journal of Obstetrics and Gynecology presents the full report from that abstract. Data are reported from 923 women followed at 85 centers where 2-year follow-up was deemed likely for at least 80% of participants. The actual follow-up rate was 79.6% (923 of 1159). The risk of death or abnormal neurodevelopmental outcome was not different for infants in the planned cesarean group (3.1%) than for infants in the planned vaginal delivery group (2.8%). A second article in this issue describes maternal outcomes at 2 years. No substantial differences were noted according to group assignment, nor were there any differences when data were compared by actual mode of delivery. The authors should be congratulated for their careful and persistent collection of follow-up data from infants and mothers in this study. Readers should be equally careful and persistent in sorting through the analyses. Some will express frustration with the investigators for their seemingly contradictory results: Does cesarean delivery reduce the risks of vaginal breech delivery for the infant and, if so, at what cost to the mother? What should the clinician take from this study? These lessons at least are valid: Clinical research, especially when carefully done and completely reported, is always messy; short-term outcomes are not good surrogates for long-term outcomes; follow-up is difficult, expensive, and never as complete as one would hope. These maxims are so often true that the best lesson may be never to trust a clinical study that isn't at least a little bit messy. If a study seems too good to be true, it probably is.

      References

        • Hannah M.E.
        • Hannah W.J.
        • Hewson S.A.
        • Hodnett E.D.
        • Saigal S.
        • et al.
        Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Term Breech Trial Collaborative Group.
        Lancet. 2000; 356: 1375-1383
        • Hannah M.E.
        • Hannah W.J.
        • Hodnett E.D.
        • Chalmers B.
        • Kung R.
        • Willan A.
        • et al.
        Term Breech Trial 3-Month Follow-up Collaborative Group, outcomes at 3 months after planned cesarean vs planned vaginal delivery for breech presentation at term: the international randomized Term Breech Trial.
        JAMA. 2002; 287: 1822-1831
        • Whyte H.
        • Hannah M.
        • Saigal S.
        Outcomes of children at 2 years of age in the term breech trial.
        Am J Obstet Gynecol. 2004; 189 ([abstract]): S57