Impacted fetal head: A retrospective cohort study of emergency caesarean section


      • Impacted fetal head at caesarean section is almost as common as shoulder dystocia.
      • Impacted fetal head is as common in caesarean sections prior to, as at full cervical dilatation.
      • Complications of impacted fetal head are independent of those of second-stage caesarean.
      • Impacted fetal head at caesarean section is variably managed within UK maternity units.
      • Junior obstetricians are more likely to diagnose an impacted fetal head than consultants.



      To investigate risk factors, management and outcomes of impacted fetal head (IFH) at caesarean section (CS).

      Study design

      This is a retrospective cohort study of all women with singleton, cephalic pregnancies who had an emergency CS during one-year (2016) at North Bristol NHS Trust, UK (n = 838).
      The incidence of caesarean section at full dilatation (CSFD) and IFH were calculated using the annual birth rate. To identify risk factors for IFH, maternal, perinatal and intrapartum characteristics were compared according to the presence or absence of IFH, and separately for first- and second-stage CS. Techniques employed to disimpact the fetal head were described. Univariable and multivariable comparisons of maternal and perinatal outcomes were made between cases with and without an IFH. Characteristics and outcomes were compared using modified Poisson regression.


      CSFD accounted for 2.1 % of all births. IFH complicated 1.5 % of all births (11.3 % of emergency CS), with 55.8 % occurring prior to full cervical dilatation.
      Increased rates of IFH at CS were associated with: oxytocin augmentation (RR = 2.47 [1.61–3.80]), full cervical dilatation (RR = 4.24 [2.96–6.07], mid/low station (RR = 4.14 [2.72–6.32]), moulding (RR = 4.39 [2.55–7.54]) and caput (RR = 6.60 [3.09–14.10]). Junior operators documented IFH more than consultants (RR = 9.61 [1.35–68.2]).
      The strategies recorded for managing IFH included: tocolysis, reverse breech extraction and vaginal push up (33.7 %, 14.7 % and 11.6 % cases respectively) with two or more techniques used in 21.1 % cases.
      IFH at CS was independently associated with an increased risk of uterine extensions (RR = 3.09 [1.96–4.87]) and a composite adverse perinatal outcome (RR = 1.66 [1.21–2.28]).


      IFH is a common and heterogeneous complication associated with increased complications for both mother and baby, independent of those of CSFD. Obstetricians must remain vigilant to the possibility of IFH at all emergency CS, particularly those at full cervical dilatation or with evidence of obstructed labour. There is an urgent need for a standardised management algorithm and training in evidence-based disimpaction techniques.


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

      Purchase one-time access:

      Academic and Personal
      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'


        • Rice A.
        • Tydeman G.
        • Briley A.
        • Seed P.T.
        The impacted foetal head at caesarean section: incidence and techniques used in a single UK institution.
        J Obstet Gynaecol. 2019; 10: 1-4
        • Resolution N.
        The Early Notification scheme progress report: collaboration and improved experience for families.
        2019: 1-70
        • Steer P.J.
        Is a fractured skull discovered in the neonate after caesarean section delivery always evidence of negligence?.
        BJOG Int J Obstet Gynaecol. 2016; 123: 336
        • Walker K.F.
        • Thornton J.G.
        “Negligent” technique for dis-impacting the fetal head at caesarean section: a scientific opinion paper.
        BJOG Int J Obstet Gynaecol. 2013; 120: 459
        • Lock M.
        Inquest into the death of Nixon Martin Tonkin.
        2017: 1-31
        • Manning J.B.
        • Tolcher M.C.
        • Chandraharan E.
        • Rose C.H.
        Delivery of an impacted fetal head during cesarean: a literature review and proposed management algorithm.
        Obstet Gynecol Surv. 2015; 70: 719-724
        • Jeve Y.B.
        • Navti O.B.
        • Konje J.C.
        Comparison of techniques used to deliver a deeply impacted fetal head at full dilation: a systematic review and meta-analysis.
        BJOG Int J Obstet Gynaecol. 2015; 123: 337-345
        • Tempest N.
        • Hart A.
        • Walkinshaw S.
        • Hapangama D.K.
        A re-evaluation of the role of rotational forceps: retrospective comparison of maternal and perinatal outcomes following different methods of birth for malposition in the second stage of labour.
        BJOG Int J Obstet Gynaecol. 2013; 120: 1277-1284
        • Unterscheider J.
        • McMenamin M.
        • Cullinane F.
        Rising rates of caesarean deliveries at full cervical dilatation: a concerning trend.
        Eur J Obstet Gynecol Reprod Biol. 2011; 157: 141-144
        • Loudon J.A.Z.
        • Groom K.M.
        • Hinkson L.
        • Harrington D.
        • Paterson-Brown S.
        Changing trends in operative delivery performed at full dilatation over a 10-year period.
        J Obstet Gynaecol. 2010; 30: 370-375
        • Corry E.M.A.
        • Ramphul M.
        • Rowan A.M.
        • Segurado R.
        • Mahony R.M.
        • Keane D.P.
        Exploring full cervical dilatation caesarean sections–A retrospective cohort study.
        Eur J Obstet Gynecol Reprod Biol. 2018; 224: 188-191
        • Davis G.
        • Fleming T.
        • Ford K.
        • Mouawad M.R.
        • Ludlow J.
        Caesarean section at full cervical dilatation.
        Aust N Z J Obstet Gynaecol. 2015; 55: 565-571
        • Berhan Y.
        • Berhan A.
        A meta-analysis of reverse breech extraction to deliver a deeply impacted head during cesarean delivery.
        Int J Gynecol Obstet. 2014; 124: 99-105
        • Cornthwaite K.
        • Bahl R.
        • Lenguerrand E.
        • Winter C.
        • Kingdom J.
        • Draycott T.
        Impacted foetal head at caesarean section: a national survey of practice and training.
        J Obstet Gynaecol. 2020; : 1-7
        • Sung J.F.
        • Daniels K.I.
        • Brodzinsky L.
        • El-Sayed Y.Y.
        • Caughey A.B.
        • Lyell D.J.
        Cesarean delivery outcomes after a prolonged second stage of labor.
        Am J Obstet Gynecol. 2007; 197: 306.e1-306.e5
        • Mckelvey A.
        • Ashe R.
        • Mckenna D.
        • Roberts R.
        Caesarean section in the second stage of labour: a retrospective review of obstetric setting and morbidity.
        J Obstet Gynaecol. 2010; 30: 264-267
        • Asıcıoglu O.
        • Güngördük K.
        • Yildirim G.
        • Asıcıoglu B.B.
        • Güngördük ÖÇ
        • Ark C.
        • et al.
        Second-stage vs first-stage caesarean delivery: comparison of maternal and perinatal outcomes.
        J Obstet Gynaecol. 2014; 34: 598-604
        • Allen V.M.
        • O’Connell C.M.
        • Baskett T.F.
        Maternal and perinatal morbidity of caesarean delivery at full cervical dilatation compared with caesarean delivery in the first stage of labour.
        BJOG Int J Obstet Gynaecol. 2005; 112: 986-990
        • David M.
        • Halle H.
        • Lichtenegger W.
        • Sinha P.
        • Zimmermann T.
        Nitroglycerin to facilitate fetal extraction during cesarean delivery.
        Obstet Gynecol. 1998; 91: 119-124
        • Landesman R.
        • Graber E.A.
        Abdominovaginal delivery - modification of the cesarean-section operation to facilitate delivery of the impacted head.
        Am J Obstet Gynecol. 1984; 148: 707-710
        • Nooh A.M.
        • Abdeldayem H.M.
        • Ben-Affan O.
        Reverse breech extraction versus the standard approach of pushing the impacted fetal head up through the vagina in caesarean section for obstructed labour: a randomised controlled trial.
        J Obstet Gynaecol. 2017; 37: 459-463
        • Brennand J.E.
        • Millns P.
        • Yentis S.
        • Hinshaw H.K.S.
        RCOG Good Practice No 11: classification of urgency of caesarean section - a continuum of risk.
        • Kadji C.
        • Cannie M.M.
        • Carlin A.
        • Jani J.C.
        Protocol for the prospective observational clinical study: estimation of fetal weight by MRI to PREdict neonatal MACROsomia (PREMACRO study) and small-for-gestational age neonates.
        BMJ Open. 2019; 9e027160
        • Zou G.
        A modified poisson regression approach to prospective studies with binary data.
        Am J Epidemiol. 2004; 159: 702-706
        • O’Brien S.
        • Day F.
        • Lenguerrand E.
        • Cornthwaite K.
        • Edwards S.
        • Siassakos D.
        Rotational forceps versus manual rotation and direct forceps: a retrospective cohort study.
        Eur J Obstet Gynecol Reprod Biol. 2017; 212: 119-125
        • Seal S.L.
        • Dey A.
        • Barman S.C.
        • Kamilya G.
        • Mukherji J.
        • Onwude J.L.
        Randomized controlled trial of elevation of the fetal head with a fetal pillow during cesarean delivery at full cervical dilatation.
        Int J Gynaecol Obstet. 2016; 133: 178-182
        • Saha P.K.
        Second stage caesarean section: evaluation of Patwardhan technique.
        J Clin Diagn Res. 2014; : 1-3
        • Girault A.
        • Goffinet F.
        • Ray C.L.
        • Azria E.
        • Barjat T.
        • Bertholdt C.
        • et al.
        Reducing neonatal morbidity by discontinuing oxytocin during the active phase of first stage of labor: a multicenter randomized controlled trial STOPOXY.
        BMC Pregnancy Childb. 2020; 20: 640
        • Lenz F.
        • Kimmich N.
        • Zimmermann R.
        • Kreft M.
        Maternal and neonatal outcome of reverse breech extraction of an impacted fetal head during caesarean section in advanced stage of labour: a retrospective cohort study.
        BMC Pregnancy Childb. 2019; : 1-8
        • Fasubaa O.B.
        • Ezechi O.C.
        • Orji E.O.
        • Ogunniyi S.O.
        • Akindele S.T.
        • Loto O.M.
        • et al.
        Delivery of the impacted head of the fetus at caesarean section after prolonged obstructed labour: a randomised comparative study of two methods.
        J Obstet Gynaecol. 2002; 22: 375-378