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We thank Professor Tullio Ghi and colleagues for their interest in our recent article1Turner J.M. Mitchell M.D. Kumar S.S. The physiology of intrapartum fetal compromise at term.Am J Obstet Gynecol. 2020; 222: 17-26Abstract Full Text Full Text PDF PubMed Scopus (40) Google Scholar on the physiology of intrapartum fetal compromise (IFC). Although they agree with our assessment that the cerebroplacental ratio (CPR) has relatively poor predictive utility for IFC, they quite reasonably raise the question whether the real value of CPR lies in its negative predictive value for this complication in light of their recent publication.2Dall’Asta A. Ghi T. Rizzo G. et al.Cerebroplacental ratio assessment in early labor in uncomplicated term pregnancy and prediction of adverse perinatal outcome: prospective multicenter study.Ultrasound Obstet Gynecol. 2019; 53: 481-487Crossref PubMed Scopus (28) Google Scholar We agree with this assessment, and indeed their findings concur with our data as well.3Turner J.M. Flatley C. Kumar S. A low fetal cerebroplacental ratio confers a greater risk of intrapartum fetal compromise and adverse neonatal outcomes in low risk multiparous women at term.Eur J Obstet Gynecol Reprod Biol. 2018; 230: 15-21Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar, 4Bligh L.N. Alsolai A.A. Greer R.M. Kumar S. Cerebroplacental ratio thresholds measured within 2 weeks before birth and risk of Cesarean section for intrapartum fetal compromise and adverse neonatal outcome.Ultrasound Obstet Gynecol. 2018; 52: 340-346Crossref PubMed Scopus (32) Google Scholar, 5Bligh L.N. Al Solai A. Greer R.M. Kumar S. Diagnostic performance of cerebroplacental ratio thresholds at term for prediction of low birthweight and adverse intrapartum and neonatal outcomes in a term, low-risk population.Fetal Diagn Ther. 2018; 43: 191-198Crossref PubMed Scopus (15) Google Scholar, 6Bligh L.N. Alsolai A. Greer R.M. Kumar S. Screening for adverse perinatal outcomes: uterine artery Doppler, cerebroplacental ratio and estimated fetal weight in low-risk women at term.J Matern Fetal Neonat Med. 2018; 31: 3301-3307Crossref PubMed Scopus (8) Google Scholar The problem, however, as we see it, is that it would be extremely difficult in clinical practice, in an era where women often embark on a pregnancy with significant risk factors (late maternal age, obesity, maternal comorbidities, poor socioeconomic status, and so on), to place overreliance on a single measure of fetal well-being and thus perhaps decide against continuous fetal monitoring in labor or choose an alternative place of birth where operative facilities may not be immediately available. We completely agree that further research is needed to develop a better prelabor test that identifies women at either high or low risk of IFC. This test may include CPR, other fetal Doppler parameters, or placental biomarkers.7Bligh L.N. Greer R.M. Kumar S. The relationship between maternal placental growth factor levels and intrapartum fetal compromise.Placenta. 2016; 48: 63-67Crossref PubMed Scopus (22) Google Scholar, 8Bligh L.N. Alsolai A.A. Greer R.M. Kumar S. Prelabor screening for intrapartum fetal compromise in low-risk pregnancies at term: cerebroplacental ratio and placental growth factor.Ultrasound Obstet Gynecol. 2018; 52: 750-756Crossref PubMed Scopus (24) Google Scholar, 9Sherrell H.C. Clifton V.L. Kumar S. Pre-labor screening at term using the cerebroplacental ratio and placental growth factor: a pragmatic randomized open label phase 2 trial.Am J Obstet Gynecol. 2020; ([Epub ahead of print])Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar However, we caution10Kumar S. Figueras F. Ganzevoort W. Turner J. McCowan L. Using cerebroplacental ratio in non-SGA fetuses to predict adverse perinatal outcome: caution is required.Ultrasound Obstet Gynecol. 2018; 52: 427-429Crossref PubMed Scopus (13) Google Scholar against the routine use of CPR in clinical practice because of its relatively modest positive and negative likelihood ratios even in a high-risk cohort,11Conde-Agudelo A. Villar J. Kennedy S.H. Papageorghiou A.T. Predictive accuracy of cerebroplacental ratio for adverse perinatal and neurodevelopmental outcomes in suspected fetal growth restriction: systematic review and meta-analysis.Ultrasound Obstet Gynecol. 2018; 52: 430-441Crossref PubMed Scopus (67) Google Scholar wherein its performance would be expected to be superior compared with its use in a low-risk population. In our view, premature adoption of CPR without good evidence could lead to unnecessary anxiety for women, increased obstetric intervention, and delivery at earlier gestations. More research is required to develop a suitable screening test for IFC and other late-pregnancy adverse outcomes. Other causes of fetal brain injuryAmerican Journal of Obstetrics & GynecologyVol. 223Issue 2PreviewYour recent publication from Al-Haddad et al1 struck a cord with me as I read the print copy, old fashioned I know. The Al-Haddad et al article about fetal origins focused only on infections; however, in the same issue there is a very good clinical opinion from Caritis and Panigrahy2 about maternal opioids and fetal brain development. Another interest of mine, antenatal corticosteroids, also has increasing literature about fetal brain effects.3,4 It is not all just infection that may be causing mental illness in later life. Full-Text PDF