Ultrasound Obstet Gynecol 2005; 25: 160164Published online 15 November 2004 in Wiley InterScience !!!"interscience"!iley"com#" DOI: 10"1002$uo%"1&6&Ultrasound detection of nuchal cord prior to labor inductionand the risk of Cesarean section'" P'(')(IN'* P" +,-(I'N .nd '" /01NI012Department of Obstetrics and Gynaecology, University College London Hospitals, London, UKKEYWORDS: 3es.re.n section; induction; nuch.l cord; 4re%n.ncy; ultr.sound!S"RC"Objectives To investigate the ability of ultrasound todetect the presence of a nuchal cord immediately prior toinduction of labor and the association of its presence withdelivery by Cesarean sectionMethods ! transabdominal ultrasound scan using gray"scale and color Doppler imaging was performedimmediately prior to induction of labor in #$% women ina prospective study to assess the presenceof a nuchal cordThe presence of a nuchal cord was classified as present,absent or uncertain The outcomes of labor, delivery andthe neonates were obtained from the patient notes afterdeliveryResults ! nuchal cord was present at &$' of deliveriesThe incidence was not affected by parity, fetal positionorreduced amniotic fluid volume The sensitivity ofultrasound in diagnosing a nuchal cord was ()*',with specificity, positive and negative predictive valuesof $+', #%' and $*', respectively The presence ofa nuchal cord did not significantly increase the ris, ofdelivery by Cesarean section -(*' vs #$'. relative ris,5 #. %*' C/, +$+0&$)1, instrumental delivery fordelivery, an !pgar score 6 ) at & min, arterial cord pH6 )& or neonatal unit admissionConclusions The sensitivity of the ultrasound diagnosisof a nuchal cord is low prior to induction of labor atterm ! nuchal cord does not appear to increase the ris,of Cesarean section or of poor neonatal outcome The lowultrasound detection rate of a nuchal cord limits its use indecision ma,ing prior to induction of labor in high"ris,pregnancies Copyright #++2 /3UOG 4ublished by5ohn 6iley 7 3ons, LtdI#"RODUC"IO#Nuch.l cord is de7ined .s .n umbilic.l cord th.t 4.sses8609 .round the 7et.l nec:" ;he 4rev.lence .t deliveryh.s been re4orted .s bein% bet!een 6< .nd 8&6 3henies Ae!s* Fondon W31' 6G2* 1@ eCm.il: e"H.uni.uDIucl".c"u:#!ccepted8 && 5une #++23o4yri%ht 2004 IS1+)" Published by /ohn Wiley J Sons* Ftd" +(I)IN0F P0P'(9uchal cord prior to labor induction $%$ultr.sound h.s .lso been used* but it .44e.rs to h.ve little.dv.nt.%e over color Bo44ler im.%in%2=";he 4resence o7 . nuch.l cord h.s been .ssoci.ted!ith m.ny di77erent 7.ctors in the mother* 7etus* cord*4l.cent..ndl.bor.nd!ith.less7.vor.ble7et.loutcome;ho!ever* the m.Hority o7 these studies .re c.se re4orts orsm.ll series";he im4.ct o7 . nuch.l cord on induction o7 l.bor isun:no!n .nd there .re no studies th.t h.ve s4eci7ic.llystudied this%rou4 o7 !omen"In . recentretros4ectivec.secontrol study (ho.des et al"4 7ound th.t . nuch.l cord!.s .ctu.lly .n inde4endent ris: 7.ctor 7or induction o7l.bor" In this study they noted th.t .ny .dverse e77ects o7. nuch.l cord .44e.red to be only tr.nsient";he obHectives o7 the 4resent study !ere: 1# toinvesti%.te the .bility o7 ultr.sound to detect . nuch.lcord immedi.tely 4rior to induction o7 l.bor .t term.nd 2# to investi%.te i7 . nuch.l cord durin% l.bor is.ssoci.ted !ith .n incre.sed r.te o7 delivery by 3es.re.nsection" Eor both determin.tions !e used nuch.l cord.t delivery .s the %old st.nd.rd !ith !hich to com4.re*.ssumin% th.t the cord 4osition !ill not ch.n%e durin%l.bor"&E"'ODSIn . 4ros4ective study bet!een /une 2001 .nd November2008 !e recruited 2=> !omen under%oin% inductiono7 l.bor .7ter 86 !ee:s, %est.tion .t 1niversity 3olle%eGos4it.l* Fondon* 1@" 'thic.l .44rov.l !.s obt.ined7rom the ;rust 'thics 3ommittee .nd !ritten in7ormedconsent !.s obt.ined 7rom the !omen" 1sin% .n 0lo:.1&00 ultr.sound m.chine 0lo:. 3o" Ftd* Ait.:.Cshi*;o:yo* /.4.n# !ith . 8"5CAGK .bdomin.l 4robe* .tr.ns.bdomin.l ultr.sound sc.n !.s 4er7ormed usin%%r.yCsc.le .nd color Bo44ler im.%in% immedi.tely 4riorto induction o7 l.bor"Presence o7 the cord !.s sou%ht in the tr.nsverse .nds.%itt.l 4l.ne o7 the nec:.nd . nuch.l cord !.s di.%nosedi7 the cord !.s visu.liKed lyin% .round .t le.st three o7the 7our sides o7 the nec:" ;he 4resence o7 nuch.l cordon sc.n !.s cl.ssi7ied .s 4resent* not 4resent or uncert.in!hen . cle.r vie! o7 .ll sides o7 the nec: could not beobt.ined#" 0ll the ultr.sound sc.ns !ere 4er7ormed by thes.me o4er.tor '"P"# .nd the !omen .nd clinici.ns !ereblinded to the results";he outcomes o7 the l.bor* delivery .nd neon.tes !ereobt.ined 7rom the !omen,s c.se notes .7ter delivery"RESU("S;he indic.tions 7or induction included 4ostm.turity n 51&1#* m.tern.l hy4ertensive dise.se n 5 1>#* intr.uterine%ro!th restriction I1)(# or isol.ted reduced .mniotic7luid volume n 5 1* 4rolon%ed ru4ture o7 the memCbr.nes .t term n 5 15#* 4reCeDistin% .nd %est.tion.l#di.betes n 5 12#* m.tern.l reLuest n 5 12#* 4oor obstetCric history n 5 12# .nd ?other, indic.tions n 5 81#""able $ ;he di.%nosis o7 . nuch.l cord by ultr.sound 4rior toinduction o7 l.bor4arameter n ' L:3ord 4resent on ultr.sound true 4ositives# 1= 843ord .bsent on ultr.sound 7.lse ne%.tives# 80 5=Nec: not seen on ultr.sound 4 =Nuch.l cord .bsent .t delivery n 5 283ord .bsent on ultr.sound true ne%.tives# 1&4 &83ord 4resent on ultr.sound 7.lse 4ositives# 44 1>Nec: not seen on ultr.sound 1> =Sensitivity 8=S4eci7icity =0Positive 4redictive v.lue 2>Ne%.tive 4redictive v.lue =5Positive test result 1"=6Ne%.tive test result 0"&=F(* li:elihood r.tio"0 nuch.l cord !.s 4resent in 1=< o7 deliveries" 0sin%le loo4 o7 cord !.s seen in 14"52"2=#*occi4ito4osterior +P# 4osition on ultr.sound (( 5indeD 0EI# o7 6 5"0 cm (( 5 0">2; >5< 3I* 0"441"=>#di.%nosin% . nuch.l cord 4rior to induction o7 l.bor !.slo!er 7or .n +P 4osition 2>1"=4#"in 11$>= 1116 !omen th.n h.s 4reviously been re4orted* des4itethe use o7 color Bo44ler im.%in%" ;he s4eci7icity !.ssimil.r to th.t obt.ined by other %rou4s" ;here .re sever.l4ossiblere.sons7orthis"Eirst*them.Horityo7thesestudiesh.ve sc.nned !omen throu%hout 4re%n.ncy* !here.s the!omen in the 4resent study !ere sc.nned only once .nd.ll !ere bet!een 86 .nd 42 !ee:s, %est.tion" In 7.ct&8< !ere more th.n 40 !ee:s, %est.tion .nd 5>< !ere%re.ter th.n 41 !ee:s, %est.tion" Second* it m.y be th.tit is 4.rticul.rly di77icult to visu.liKe the 7et.l nec: onultr.sound in !omen under%oin% induction o7 l.bor";he di77iculty encountered in visu.liKin% the nuch.lcord .t this %est.tion .nd 4rior to induction o7 l.bor m.ybe due to 7et.l cro!din%* lo! 4osition o7 the 7et.l he.d orreduced .mniotic 7luid volume" Eor the .7orementionedre.sons !e occ.sion.lly 7ound it di77icult to see cle.rly .tle.st three out o7 7our sides o7 the 7et.l nec: 28 !omen#";his is 4.rticul.rly di77icult in the +P 4osition >=$2=>*i"e" 84< o7 the !omen in the 4resent study#* !here .tbest o7ten only t!o sides o7 the nec: c.n be seen" ;he7.lseC4ositive r.te o7 ultr.sound di.%nosis o7 . nuch.lcord h.s been described .s bein% hi%her 7or color Bo44lerth.n 7or %r.yCsc.le im.%in%12 .nd this is 4rob.bly dueto seein% the cord beside r.ther th.n .round the nec:*!hich !.s the c.se in 1>< o7 the !omen in the 4resentstudy" E.lseCne%.tive results h.ve been eD4l.ined by the3o4yri%ht 2004 IS1+)" Published by /ohn Wiley J Sons* Ftd" Ultrasound Obstet Gynecol 2005; 25: 160164"