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We are delighted that our article1Chen H.Y. Chauhan S.P. Ananth C.V. Vintzileos A.M. Abuhamad A.Z. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States.Am J Obstet Gynecol. 2011; 204: 491.e1-491.e10Abstract Full Text Full Text PDF Scopus (94) Google Scholar exploring the association between the utilization of electronic fetal monitoring (EFM) and risk of adverse infant morbidity and mortality has evinced interest from Klebanoff et al.2Klebanoff M.A. Branum A.M. Lynch C.D. Schoendorf K.C. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States (letter).Am J Obstet Gynecol. 2011; 205 (exx)Google Scholar At the outset, we were surprised to note that Klebanoff et al2Klebanoff M.A. Branum A.M. Lynch C.D. Schoendorf K.C. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States (letter).Am J Obstet Gynecol. 2011; 205 (exx)Google Scholar have expressed concerns regarding an evaluation of the benefits of EFM based on vital statistics data when they themselves, since 1992, have collectively published at least 36 articles that are based on the vital statistics data. This irony aside, let us address the primary concerns about our publication.1Chen H.Y. Chauhan S.P. Ananth C.V. Vintzileos A.M. Abuhamad A.Z. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States.Am J Obstet Gynecol. 2011; 204: 491.e1-491.e10Abstract Full Text Full Text PDF Scopus (94) Google Scholar First, Klebanoff et al2Klebanoff M.A. Branum A.M. Lynch C.D. Schoendorf K.C. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States (letter).Am J Obstet Gynecol. 2011; 205 (exx)Google Scholar worry that we inappropriately used the vital statistics data “to make the leap from statistical association to causation.” We do not. May we point out that the very first sentence of the abstract states the objective was “to examine the association between EFM and neonatal and infant mortality as well as neonatal morbidity?” In the study design portion of the abstract, we wrote the “estimate risk ratio for association between electronic fetal heart rate monitoring and mortality.” In the introduction, we noted that “the primary objective of this study was to examine the association between EFM during labor and corrected neonatal and infant mortality in the United States.” Although it is possible to draw causal inferences, our goal was to infer only associations in the article. However, it should be also noted that we found a significant dose-response relationship between gestational age and the number needed to treat with earlier gestations requiring the least number needed to treat. Second, Klebanoff et al2Klebanoff M.A. Branum A.M. Lynch C.D. Schoendorf K.C. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States (letter).Am J Obstet Gynecol. 2011; 205 (exx)Google Scholar argue about the “potential inaccuracy of the EFM data.” Under the section of strengths and weakness section of our article,1Chen H.Y. Chauhan S.P. Ananth C.V. Vintzileos A.M. Abuhamad A.Z. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States.Am J Obstet Gynecol. 2011; 204: 491.e1-491.e10Abstract Full Text Full Text PDF Scopus (94) Google Scholar the very first limitation we acknowledged was that “studies based on birth certificates have been criticized because of the quality of the data.” Nonetheless, it is noteworthy that our finding of significant increased rate of operative deliveries for fetal distress3Garite T.J. Intrapartum fetal evaluation.in: Gabbe S.G. Niebyl J.R. Simpson J.L. Galan H. Goetzl L. Jauniaux E.R.M. Landon M. Obstetrics: normal and problem pregnancies. 5th ed. Churchill Livingstone Elsevier, Philadelphia, PA2007Google Scholar and decrease in neonatal seizures associated with EFM utilization is consistent with a metaanalysis of 12 randomized controlled trials (RCTs) on EFM.4Alfirevic Z. Devane D. Gyte G.M. Continuous cardiotocography (CTG) as a form of electronic fetal monitoring (EFM) for fetal assessment during labour.Cochrane Database Syst Rev. 2006; (CD006066)Google Scholar We do acknowledge that some degree of misclassification of EFM on vital statistics data is likely, but we wonder whether it really is possible that limitations of vital statistics provide results concordant with RCTs when focused on morbidity and not on mortality. Third, Klebanoff et al2Klebanoff M.A. Branum A.M. Lynch C.D. Schoendorf K.C. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States (letter).Am J Obstet Gynecol. 2011; 205 (exx)Google Scholar are apprehensive about the role of unmeasured confounders on our findings. Although we did not specifically draw attention to the role of unmeasured confounders on the associations that we reported, it is very unlikely that a complete adjustment for “all possible confounders” would drive the strong associations of EFM use and early neonatal deaths and a low 5 minute Apgar score that we report toward the null. In addition, we underscore the congruity of our findings and that of earlier publications, including a metaanalysis of 12 RCTs.4Alfirevic Z. Devane D. Gyte G.M. Continuous cardiotocography (CTG) as a form of electronic fetal monitoring (EFM) for fetal assessment during labour.Cochrane Database Syst Rev. 2006; (CD006066)Google Scholar After careful reading of their concerns, we affirm that our data indicate what we concluded before: “In the United States, the use of EFM was associated with a substantial decrease in early neonatal mortality and morbidity.” We do welcome large and adequately powered RCTs to disprove our conclusions; like Freeman and Nageotte,5Freeman R.K. Nageotte M.P. Comments on American College of Obstetricians and Gynecologists practice bulletin no. 106.Am J Obstet Gynecol. 2010; 202: 411-412Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar we do not subscribe to the nihilistic view of the EFM and believe that the best evidence of the benefits of EFM may not come from the small RCTs but from the largest observational study reported to date.1Chen H.Y. Chauhan S.P. Ananth C.V. Vintzileos A.M. Abuhamad A.Z. Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States.Am J Obstet Gynecol. 2011; 204: 491.e1-491.e10Abstract Full Text Full Text PDF Scopus (94) Google Scholar Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United StatesAmerican Journal of Obstetrics & GynecologyVol. 206Issue 1PreviewThe Journal recently published an article suggesting a causal association between electronic fetal monitoring (EFM) and decreased infant mortality.1 We have strong reservations regarding the ability of that paper to offer guidance regarding the effectiveness of EFM because it is inappropriate to use vital statistics data to make the leap from statistical association to causation. Full-Text PDF