The systematic error in the estimation of fetal weight and the underestimation of fetal growth restriction

Published:February 13, 2017DOI:
      Fetal growth restriction (FGR) is associated with an increased risk of perinatal morbidity and mortality and has lifetime implications for the risk of chronic medical conditions. Antenatal diagnosis of FGR remains poor, with the majority of cases remaining undiagnosed. Although several factors contribute to the underdiagnosis of FGR, the error in ultrasound estimation of fetal weight (EFW) generally is not considered in clinical practice. In this commentary, we suggest that the intrinsic, or systematic, error in ultrasound EFW is a significant factor contributing to the underestimation of fetuses predicted to have FGR and should be incorporated into screening and surveillance recommendations. To illustrate this point, we present an analytic model of published data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies characterizing and quantifying the impact of the systematic error in ultrasound EFW on the underdiagnosis of FGR. Independent of the centile at which the risk of adverse outcome related to FGR begins, whether the 10th, 5th or 3rd percentile, our analysis suggests the need to modify to the current paradigm for identifying and responding to fetuses estimated to be at risk.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Obstetrics & Gynecology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • American College of Obstetricans and Gynecologists
        Fetal Growth Restriction. ACOG Practice Bulletin No. 134.
        Obstet Gynecol. 2013; 121: 1122-1133
        • Trudell A.S.
        • Cahill A.G.
        • Tuuli M.G.
        • Macones G.A.
        • Odibo A.O.
        Risk of stillbirth after 37 weeks in pregnancies complicated by small-for-gestational-age fetuses.
        Am J Obstet Gynecol. 2013; 208: 376.e1-376.e7
        • McIntire D.D.
        • Bloom S.L.
        • Casey B.M.
        • Leveno K.J.
        Birth weight in relation to morbidity and mortality among newborn infants.
        N Engl J Med. 1999; 340: 1234-1238
        • Pilliod R.A.
        • Cheng Y.W.
        • Snowden J.M.
        • Doss A.E.
        • Caughey A.B.
        The risk of intrauterine fetal death in the small-for-gestational-age fetus.
        Am J Obstet Gynecol. 2012; 207: 318.e1-318.e6
        • Baschat A.A.
        • Viscardi R.M.
        • Hussey-Gardner B.
        • Hashmi N.
        • Harman C.
        Infant neurodevelopment following fetal growth restriction: relationship with antepartum surveillance parameters.
        Ultrasound Obstet Gynecol. 2009; 33: 44-50
        • Barker D.J.
        Adult consequences of fetal growth restriction.
        Clin Obstet Gynecol. 2006; 49: 270-283
        • Bonamy A.K.
        • Parikh N.I.
        • Cnattingius S.
        • Ludvigsson J.F.
        • Ingelsson E.
        Birth characteristics and subsequent risks of maternal cardiovascular disease: effects of gestational age and fetal growth.
        Circulation. 2011; 124: 2839-2846
        • Alfirevic Z.
        • Stampalija T.
        • Gyte G.M.
        Fetal and umbilical Doppler ultrasound in high-risk pregnancies.
        Cochrane Database Syst Rev. 2010; : CD007529
        • Ferrazzi E.
        • Bozzo M.
        • Rigano S.
        • et al.
        Temporal sequence of abnormal Doppler changes in the peripheral and central circulatory systems of the severely growth-restricted fetus.
        Ultrasound Obstet Gynecol. 2002; 19: 140-146
        • Baschat A.A.
        • Gembruch U.
        • Harman C.R.
        The sequence of changes in Doppler and biophysical parameters as severe fetal growth restriction worsens.
        Ultrasound Obstet Gynecol. 2001; 18: 571-577
        • Le Ray C.
        • Lacerte M.
        • Iglesias M.H.
        • Audibert F.
        • Morin L.
        Routine third trimester ultrasound: what is the evidence?.
        J Obstet Gynaecol Can. 2008; 30: 118-122
        • Mattioli K.P.
        • Sanderson M.
        • Chauhan S.P.
        Inadequate identification of small-for-gestational-age fetuses at an urban teaching hospital.
        Int J Gynaecol Obstet. 2010; 109: 140-143
        • Monier I.
        • Blondel B.
        • Ego A.
        • Kaminski M.
        • Goffinet F.
        • Zeitlin J.
        Poor effectiveness of antenatal detection of fetal growth restriction and consequences for obstetric management and neonatal outcomes: a French national study.
        BJOG. 2015; 122: 518-527
        • Chauhan S.P.
        • Beydoun H.
        • Chang E.
        • et al.
        Prenatal detection of fetal growth restriction in newborns classified as small for gestational age: correlates and risk of neonatal morbidity.
        Am J Perinatol. 2014; 31: 187-194
        • Verlijsdonk J.W.
        • Winkens B.
        • Boers K.
        • Scherjon S.
        • Roumen F.
        Suspected versus non-suspected small-for-gestational-age fetuses at term: perinatal outcomes.
        J Matern Fetal Neonatal Med. 2012; 25: 938-943
        • Lindqvist P.G.
        • Molin J.
        Does antenatal identification of small-for-gestational age fetuses significant improve their outcome?.
        Ultrasound Obstet Gynecol. 2005; 25: 258-264
        • Mandujano A.
        • Myers S.
        • Mercer B.M.
        Fetal growth restriction at term: impact of antenatal diagnosis on intrapartum management and newborn outcomes.
        Am J Obstet Gynecol. 2011; 204 (S120 (abstract#289))
        • Chauhan S.P.
        • Hendrix N.W.
        • Magann E.F.
        • Morrison J.C.
        • Kenney S.P.
        • Devoe L.D.
        Limitations of clinical and sonographic estimates of birthweight: experience with 1034 parturients.
        Obstet Gynecol. 1998; 91: 72-77
        • Goetzinger K.R.
        • Tuuli M.G.
        • Odibo A.O.
        • Roehl K.A.
        • Macones G.A.
        • Cahill A.G.
        Screening for fetal growth disorders by clinical exam in the era of obesity.
        J Perinatol. 2013; 33: 352-357
        • Bais J.M.
        • Eskes M.
        • Pel M.
        • Bonsel G.J.
        • Bleker O.P.
        Effectiveness of detection of intrauterine growth retardation by abdominal palpation as screening test in a low risk population: an observational study.
        Eur J Obstet Gynecol Reprod Biol. 2004; 116: 164-169
        • Sovio U.
        • White I.R.
        • Dacey A.
        • Pasupathy D.
        • Smith G.C.
        Screening for fetal growth restriction with universal third trimester ultrasonography in nulliparous women in the Pregnancy Outcome Prediction (POP) study: a prospective cohort study.
        Lancet. 2015; 386: 2089-2097
        • Hadlock F.P.
        • Harrist R.B.
        • Carpenter R.J.
        • Deter R.L.
        • Park S.K.
        Sonographic estimation of fetal weight. The value of femur length in addition to head and abdomen measurements.
        Radiology. 1984; 150: 535-540
        • Hadlock F.P.
        • Harrist R.B.
        • Sharman R.S.
        • Deter R.L.
        • Park S.K.
        Estimation of fetal weight with the use of head, body and femur measurements—a prospective study.
        Am J Obstet Gynecol. 1985; 151: 333-337
        • Shepard M.J.
        • Richards V.A.
        • Berkowitz R.L.
        • Warsof S.L.
        • Hobbins J.C.
        An evaluation of two equations for predicting fetal weight by ultrasound.
        Am J Obstet Gynecol. 1982; 142: 47-54
        • Sabbagha R.E.
        • Minogue J.
        • Tamura R.K.
        • Hungerford S.A.
        Estimation of birth weight by use of ultrasonographic formulas targeted to large-, appropriate-, small-for-gestational-age fetuses.
        Am J Obstet Gynecol. 1989; 160: 854-860
        • Dudley N.J.
        A systematic review of the ultrasound estimation of fetal weight.
        Ultrasound Obstet Gynecol. 2005; 25: 80-89
        • Buck Louis G.M.
        • Grewal J.
        • Albert P.S.
        • et al.
        Racial/ethnic standards for fetal growth: the NICHD Fetal Growth Studies.
        Am J Obstet Gynecol. 2015; 213: 449.e1-449.e41
        • Lee W.
        • Balasubramaniam M.
        • Deter R.L.
        • et al.
        New fetal weight estimation models using fractional limb volume.
        Ultrasound Obstet Gynecol. 2009; 34: 556-565
        • Hammad I.A.
        • Chauhan S.P.
        • Mlynarczyk M.
        • et al.
        Uncomplicated pregnancies and ultrasounds for fetal growth restriction: a pilot randomized clinical trial.
        Am J Perinat Rep. 2016; 6: e83-e90
        • Khoury F.R.
        • Stetzer B.
        • Myers S.A.
        • Mercer B.
        Comparison of estimated fetal weights using volume and 2-dimensional sonography and their relationship to neonatal markers of fat.
        J Ultrasound Med. 2009; 28: 309-315
        • Stratton J.F.
        • Scanaill S.N.
        • Stuart B.
        • Turner M.J.
        Are babies of normal birth weight who fail to reach their growth potential as diagnosed by ultrasound at increased risk?.
        Ultrasound Obstet Gynecol. 1995; 5: 114-118
        • Owen P.
        • Harrold A.J.
        • Farrell T.
        Fetal size and growth velocity in the prediction of intrapartum caesarean section for fetal distress.
        BJOG. 1997; 104: 445-449
        • Gordijn S.J.
        • Beune I.M.
        • Thilaganathan B.
        • et al.
        Consensus definition of fetal growth restriction: a Delphi procedure.
        Ultrasound Obstet Gynecol. 2016; 48: 333-339
        • Unterscheider J.
        • Daly S.
        • Geary M.P.
        • et al.
        Optimizing the definition of intrauterine growth restriction: the multicenter prospective PORTO Study.
        Am J Obstet Gynecol. 2013; 208: 290
        • Figueras F.
        • Gardosi J.
        Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management.
        Am J Obstet Gynecol. 2011; 204: 288-300
        • Mayer C.
        • Joseph K.S.
        Fetal growth: a review of terms, concepts and issues relevant to obstetrics.
        Ultrasound Obstet Gynecol. 2013; 41: 136-145

      Linked Article

      • Ultrasound estimated fetal weight
        American Journal of Obstetrics & GynecologyVol. 217Issue 6
        • Preview
          We read with interest the article of Lappen and Myers1 in which the authors emphasize the error in estimation of fetal weight (EFW) and its impact on underestimating fetal growth restriction (FGR). In view of this systematic error, the authors adopted an approach for enhanced surveillance of fetuses with an EFW between 10-20th percentile, and further recommend multimodal efforts to improve FGR detection and associated risks. A similar issue can likely be raised in the ultrasound identification of large-for-gestational-age infants.
        • Full-Text
        • PDF