Becauseofitslipophiliccharacter,nicotinepassesveryrapidlyintobreastmilkwhereit attainsthreefoldhigherconcentrationsthaninblood
[165,166] .Onthebasisofthevolume
ofbreastmilkconsumed,thismeansthattheinfantreceives6µgnicotinekgbodyweight daily
[165] .Cotininelevelsareanindicatorofsmokinghabitsandcorrelatewiththenumber
ofcigarettessmoked [167]
.Theinfant’surinarycotininecomesfromthecotinineinthe mother’sbreastmilk.Itisdificulttoassesswhatproportionderivesfrominhalationbecause
ofpassiveexposurebybeinginthesameroomassmokers [168]
.Theeliminationhalf-life fornicotineinbreastmilkissomewhathigherthanthatinthemother’sblood97±20vs.
81±9min;p0.05,whereascotinineconcentrationsremainfairlyconsistentduringa4-h intervalwithoutsmoking
[166] .Newborninfantsbreast-fedbysmokersandunexposedtopas-
sivesmokingshowlowplasmalevelsofnicotine0.2–1.6ngmlandcotinine5–30ngml. Newborninfantsbreast-fedbynon-smokersdidnothavemeasurableamountsofthetwo
substancesinplasma [169]
.AsshownbythedatapresentedinTable 8.7
,breast-feeding mothersclearlycontributetoraisedplasmanicotinelevels.
Nicotineandcotinineconcentrationsinbreastmilkincreasewiththenumberofcigarettes smokeddaily,withconcentrationsupto1.6ngnicotinemland20ngcotininemlhaving
beenmeasured [170]
.Concentrationsarisingasaresultofpassivesmokingaremarkedly lower.Nicotineandcotininelevelsweremeasuredbygaschromatographyin34humanmilk
samples:nicotinewasnotfoundinthe6samplesofmilkfromnon-smokersbutwasdetected inthe28samplesfromsmokersaverage:91ppb;rangingfrom20to512ppb
[171] .The
varyingnicotinelevelsdidnotcauseanyadverseeffectsinthebreast-fedchildren [171]
. Urinarycotininelevelsinbreast-fedinfantsofsmokingmothersweretentimeshigherthan
thoseinbottle-fedinfantsofsmokingmothers [172]
.Cotininelevelswerealsoincreased wheninfantsofnon-smokingmotherslivedinhouseholdswithothersmokers.Inthisgroup
thedifferencescomparedwithinfantsofsmokingmotherswereveryminimal [172]
,sug- gestingthatpassivesmokingmustberecognisedasapivotalcauseoftheaccumulationof
productsofcombustion.Inaddition,Cd
2+
levelsinbreastmilkareraisedinsmokers [27]
. Overall,breast-feedingisusefulbecausetheriskofchildhoodwheezingisreduced,even
wheremotherssmoke [173]
.Itisstillbetter–butfarfromideal–tosmokeandbreastfeed thantosmokeandnotbreastfeed
[174,175] ,althoughitisknownthatsmokersbreastfeedfor
aclearlyshorterperiodthannon-smokers [176]
,owingpossiblytoareductioninprolactin levels
[177] .Initialinvestigationsalsosuggestthatbreast-feedingfor5–6monthsbeneitsthe
child’scognitivedevelopmenttoagreaterextentthanbreast-feedingfor3months [178]
.
Infantexposurepattern Nicotinecreatinineratio
ngnicotinemgcreatinine Cotininecreatinineratio
ngcotininemgcreatinine Newborninfantsbreast-fed
bysmokingmothersand unexposedtopassivesmoking
145.0–110.0 11010–550
Non-breast-fedinfantsexposed onlytopassivesmoking
354.7–218.0 327117–780
Infantsexposedtopassivesmoking andtosmokeviabreastmilk
123.0–42.0 550225–870
Table 8.7
Urinaryexcretionofnicotineandcotinineinbreast-fedinfants [169]
Mediannicotinecreatinineandcotininecreatinineratiosandranges
8.8 Medical Care Costs Attributable to Smoking During Pregnancy
Inrecentyears,severalcalculationshavebeenmadeinanattempttoestimatetheinancial burdenonthehealthinsuranceschemes,andhenceonsociety,arisingfromsmokingdur-
ingpregnancy [179–182]
.In1993,intheUSAmedicalcareexpendituresattributableto smokingwereestimatedtobeUS50billion
[179] .Thepregnantsmokerrunsconsider-
ablerisksforherself,herpregnancyandherchild,andthisbehaviourbypregnantwomen placesamajoreconomicburdenonsociety,estimatedatUS135–167millionintheUSA
in1993 [183]
althoughothershavesuggestedaigureashighasUS1.4billion [184]
. Somestudieshaveexclusivelyconsideredcostsastheyrelatetothenewbornchildor
infant [185]
.Onerecentstudyofbirthandirst-yearcostsformothersandinfantsdemon- stratedincrementalcostsofUS23,697forplacentalabruptionandUS21,944forrespira-
torydistresssyndrome [186]
.Incontrast,costshavebeenreportedasUS914forLBW andUS428forlowerrespiratorytractinfection.Thesumoftheadditionalcostsattribut-
abletomaternalsmokingduringpregnancyforallconditionsyieldedatotalrangingfrom US1,142–1,358persmokingpregnantwoman
[186] .Similarresultshavebeenreported
inaGermanstudyfrom1999in770,744livebirthsandwitha20.3smokingprevalence amongpregnantwomen:fromthispopulationofpregnantwomen,pretermdeliveriesina
hospitalsettingincurredadditionalexpenditureof36million [187]
. Inviewofthesefactsitisanurgentprioritythateffectiveprogrammesbeinitiated
amongwomentoencouragesmokingcessationattheverystartofpregnancy.
8.9 Concluding Remarks
•
Currentknowledgeindicatesthatcigarettesmokingduringpregnancyandthebreast- feedingperiodhasconsiderableharmfuleffectsonfoetalhealthandontheinfant’s
initialgrowthphase.
•
Smokingmothersrunamajorriskfortheirchild,notonlyintermsofhigherratesofabor- tion,prematureplacentalabruptionandLBW,butalsoofmalformationscleftlippalate,
limbdefectsetc.,whiledifferingviewspersistconcerningtheriskofDownsyndrome.
•
Theseharmfuleffectsareevidentlycausedbyhypoxicreactionsduringsmoking,with subsequentincreasedlevelsofcarboxyhaemoglobin,ashasalsobeenobservedincases
ofCOpoisoningwhichhaveresultedinthebirthofmalformedinfants.Tothismustbe addedthenowprovenplacenta-toxicpropertiesofcadmium,asubstancewhichpreg-
nantwomenabsorbinincreasedamountsduringsmoking.
•
Duringtheirstmonthsoflife,largenumbersofinfantsdiefromSIDS,aconditionthat isalsotriggeredbymaternalandpassivesmoking,asshownbythedetectedpresence
ofcotinineinvictims’urineandhair.
•
Nouniiedviewcurrentlyexistsconcerningtheinvolvementofnicotineintheseharmful effects,particularlysinceonlyanimalexperimentshavebeenconductedinthisarea,and
itisquestionablewhethertheindingsobtainedcanbetransposedtohumanpregnancy.On thebasisofatleasttheexperimentalanimalstudiestodate,nomalformationshavecome
tolight.Theregulationofdopaminergicreceptorsisaltered,andwhileithasbeenpostu- latedthatcardiopulmonaryregulationisdisturbed,thishasbynomeansbeenproved.
•
Overall,almostallcomplicationsintheunbornchildoccurringduringpregnancycan beattributedtothecombustionproductsoftobacco,includingtheformationofCO.
Thisbodyofevidencemightalsojustifyreconsiderationoftheuseofsmokingcessa- tiontherapywithnicotineproductsinpregnantwomen.
•
Alongsidetheharmfuleffectstothechild,theadditionaleconomicburdenimposedon thestateandsocietyshouldbesuficientreasonforimplementingeffectivesmoking
cessationprogrammes.
References
1.Anonym 1994 Dokumentation über Mutterschaftsvorsorge und Entbindungen, Tabelle 3. KassenärztlicheBundesvereinigung,Köln
2.VoigtM,HesseV,WermkeK,FrieseK2001RaucheninderSchwangerschaft.Risikofürdas WachstumdesFeten.KinderärztlPraxis72:26–29
3.AndresRL,DayMC2000Perinatalcomplicationsassociatedwithmaternaltobaccouse. SeminNeonatol53:231–241
4.SalihuHM,AliyuMH,Pierre-LouisBJ,AlexanderGR2003Levelsofexcessinfantdeaths attributabletomaternalsmokingduringpregnancyintheUnitedStates.MaternChildHealthJ
74:219–227 5.OckeneJ,MaY,ZapkaJ,PbertL,ValentineGK,StoddardA2002Spontaneouscessationof
smokingandalcoholuseamonglow-incomepregnantwomen.AmJPrevMed233:150–159 6.WassermanGA,LiuX,PineDS,GrazianoJH2001Contributionofmaternalsmokingduring
pregnancyandleadexposuretoearlychildbehaviorproblems.NeurotoxicolTeratol231:13–21 7.LackmannGM,AngererJ,TollnerU2000Parentalsmokingandneonatalserumlevelsof-
polychlorinatedbiphenylsandhexachlorobenzene.PediatrRes475:598–601 8.AhluwaliaIB,Grummer-StrawnL,ScanlonKS1997Exposuretoenvironmentaltobacco
smokeandbirthoutcome:increasedeffectsonpregnantwomenaged30yearsorolder.Am JEpidemiol1461:42–47
9.AnanthCV,SavitzDA,LutherER1996Maternalcigarettesmokingasariskfactorforplacental abruption,placentaprevia,anduterinebleedinginpregnancy.AmJEpidemiol1449:881–889
10.CnattingiusS,AxelssonO,EklundG,LindmarkG1985Smoking,maternalage,andfetal growth.ObstetGynecol664:449–452
11.WangX,TagerIB,VanVunakisH,SpeizerFE,HanrahanJP1997Maternalsmokingduring pregnancy,urinecotinineconcentrations,andbirthoutcomes.Aprospectivecohortstudy.Int
JEpidemiol265:978–988 12.PoppeWA,DrijkoningenM,IdePS,LauwerynsJM,VanAsscheFA1996Langerhans’cells
andL1antigenexpressioninnormalandabnormalsquamousepitheliumofthecervicaltrans- formationzone.GynecolObstetInvest413:207–213
13.BernsteinL,PikeMC,LoboRA,DepueRH,RossRK,HendersonBE1989Cigarettesmok- inginpregnancyresultsinmarkeddecreaseinmaternalhCGandoestradiollevels.BrJObstet
Gynaecol961:92–96 14.BoyceA,SchwartzD,HubertC,CedardL,DreyfusJ1975Smoking,humanplacentallac-
togenandbirthweight.BrJObstetGynaecol8212:964–967