Placenta: How it works, what's normal - Mayo Clinic

The placenta is an organ that develops in your uterus during pregnancy. This structure provides oxygen and nutrients to your growing baby and removes waste ... COVID-19:Advice,updatesandvaccineoptions Weareopenforsafein-personcare. Learnmore: MayoClinicfactsaboutcoronavirusdisease2019(COVID-19) OurCOVID-19patientandvisitorguidelines,plustrustedhealthinformation Lateston COVID-19vaccination bysite: Arizonapatientvaccinationupdates Arizona, Floridapatientvaccinationupdates Florida, Rochesterpatientvaccinationupdates Rochesterand MayoClinicHealthSystempatientvaccinationupdates MCHS Skiptositenavigation SkiptoContent ThiscontentdoesnothaveanEnglishversion. ThiscontentdoesnothaveanArabicversion. 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Whatdoestheplacentado? Theplacentaisanorganthatdevelopsinyouruterusduringpregnancy.Thisstructureprovidesoxygenandnutrientstoyourgrowingbabyandremoveswasteproductsfromyourbaby'sblood.Theplacentaattachestothewallofyouruterus,andyourbaby'sumbilicalcordarisesfromit.Theorganisusuallyattachedtothetop,side,frontorbackoftheuterus.Inrarecases,theplacentamightattachinthelowerareaoftheuterus.Whenthishappens,it'scalledalow-lyingplacenta(placentaprevia). Whataffectsplacentalhealth? Variousfactorscanaffectthehealthoftheplacentaduringpregnancy,withsomeunderyourcontrolandsomenot.Forexample: Maternalage.Someplacentalproblemsaremorecommoninolderwomen,especiallyafterage40. Abreakinyourwaterbeforelabor.Duringpregnancy,yourbabyissurroundedandcushionedbyafluid-filledmembranecalledtheamnioticsac.Ifthesacleaksorbreaksbeforelaborbegins,alsocalledyourwaterbreaking,theriskofcertainplacentalproblemsincreases. Highbloodpressure.Highbloodpressurecanaffectyourplacenta. Twinorothermultiplepregnancy.Ifyou'repregnantwithmorethanonebaby,youmightbeatincreasedriskofcertainplacentalproblems. Blood-clottingdisorders.Anyconditionthateitherimpairsyourblood'sabilitytoclotorincreasesitslikelihoodofclottingincreasestheriskofcertainplacentalproblems. Previousuterinesurgery.Ifyou'vehadaprevioussurgeryonyouruterus,suchasaC-sectionorsurgerytoremovefibroids,you'reatincreasedriskofcertainplacentalproblems. Previousplacentalproblems.Ifyou'vehadaplacentalproblemduringapreviouspregnancy,youmighthaveahigherriskofexperiencingitagain. Substanceuse.Certainplacentalproblemsaremorecommoninwomenwhosmokeorusecocaineduringpregnancy. Abdominaltrauma.Traumatoyourabdomen—suchasfromafall,autoaccidentorothertypeofblow—increasestheriskoftheplacentaprematurelyseparatingfromtheuterus(placentaabruption). Whatarethemostcommonplacentalproblems? Openpop-updialogbox Placentalabruption Close Placentalabruption Placentalabruption Theplacentaisanorganthatdevelopsintheuterusduringpregnancy.Placentalabruptionoccurswhentheplacentaseparatesfromtheinnerwalloftheuterusbeforebirth.Placentalabruptioncandeprivethebabyofoxygenandnutrientsandcauseheavybleedinginthemother.Insomecases,earlydeliveryisneeded. Openpop-updialogbox Placentaprevia Close Placentaprevia Placentaprevia Theplacentaisastructurethatdevelopsintheuterusduringpregnancy.Inmostpregnancies,theplacentaislocatedatthetoporsideoftheuterus.Inplacentaprevia,theplacentaislocatedlowintheuterus.Theplacentamightpartiallyorcompletelycoverthecervix,asshownhere.Placentapreviacancauseseverebleedinginthemotherbeforeorduringdelivery.AC-sectiondeliverymightberequired. Duringpregnancy,possibleplacentalproblemsincludeplacentalabruption,placentapreviaandplacentaaccreta.Theseconditionscancausepotentiallyheavyvaginalbleeding.Afterdelivery,retainedplacentaissometimesaconcern.Here'swhatyouneedtoknowabouttheseconditions: Placentalabruption.Iftheplacentapeelsawayfromtheinnerwalloftheuterusbeforedelivery—eitherpartiallyorcompletely—aconditionknownasplacentalabruptiondevelops.Thiscandeprivethebabyofoxygenandnutrientsandcauseyoutobleedheavily.Placentaabruptioncouldresultinanemergencysituationrequiringearlydelivery. Placentaprevia.Thisconditionoccurswhentheplacentapartiallyortotallycoversthecervix—theoutletfortheuterus.Placentapreviaismorecommonearlyinpregnancyandmightresolveastheuterusgrows. Placentapreviacancauseseverevaginalbleedingduringpregnancyordelivery.Themanagementofthisconditiondependsontheamountofbleeding,whetherthebleedingstops,howfaralongyourpregnancyis,thepositionoftheplacenta,andyourandyourbaby'shealth.Ifplacentapreviapersistslateinthethirdtrimester,yourhealthcareproviderwillrecommendaC-section. Placentaaccreta.Typically,theplacentadetachesfromtheuterinewallafterchildbirth.Withplacentaaccreta,partoralloftheplacentaremainsfirmlyattachedtotheuterus.Thisconditionoccurswhenthebloodvesselsandotherpartsoftheplacentagrowtoodeeplyintotheuterinewall.Thiscancauseseverebloodlossduringdelivery. Inaggressivecases,theplacentainvadesthemusclesoftheuterusorgrowsthroughtheuterinewall.YourhealthcareproviderwilllikelyrecommendaC-sectionfollowedbyremovalofyouruterus. Retainedplacenta.Iftheplacentaisn'tdeliveredwithin30minutesafterchildbirth,it'sknownasaretainedplacenta.Aretainedplacentamightoccurbecausetheplacentabecomestrappedbehindapartiallyclosedcervixorbecausetheplacentaisstillattachedtotheuterinewall.Leftuntreated,aretainedplacentacancausesevereinfectionorlife-threateningbloodloss. Whataresignsorsymptomsofplacentalproblems? Consultyourhealthcareproviderduringpregnancyifyouhave: Vaginalbleeding Abdominalpain Backpain Uterinecontractions WhatcanIdotoreducemyriskofplacentalproblems? Mostplacentalproblemscan'tbedirectlyprevented.However,youcantakestepstopromoteahealthypregnancy: Visityourhealthcareproviderregularlythroughoutyourpregnancy. Workwithyourhealthcareprovidertomanageanyhealthconditions,suchashighbloodpressure. Don'tsmokeorusedrugs. TalkwithyourdoctoraboutthepotentialrisksbeforedecidingtopursueanelectiveC-section. Ifyou'vehadaplacentalproblemduringapreviouspregnancyandareplanninganotherpregnancy,talktoyourhealthcareprovideraboutwaystoreducetheriskofexperiencingtheconditionagain.Alsotellyourhealthcareproviderifyou'vehadsurgeryonyouruterusinthepast.Expectyourhealthcareprovidertomonitoryourconditioncloselythroughoutthepregnancy. Howistheplacentadelivered? Ifyoudeliveryourbabyvaginally,you'llalsodelivertheplacentavaginally—duringwhat'sknownasthethirdstageoflabor. Afteryougivebirth,you'llcontinuetohavemildcontractions.Yourhealthcareprovidermightgiveyouamedicationcalledoxytocin(Pitocin)tocontinueuterinecontractionsandreducepostpartumbleeding.Yourhealthcareprovidermightalsomassageyourlowerabdomentoencourageyouruterustocontractandexpeltheplacenta.Youmightbeaskedtopushonemoretimetodelivertheplacenta. IfyouhaveaC-section,yourhealthcareproviderwillremovetheplacentafromyouruterusduringtheprocedure. Yourhealthcareproviderwillexaminetheplacentatomakesureit'sintact.Anyremainingfragmentsmustberemovedfromtheuterustopreventbleedingandinfection.Ifyou'reinterested,asktoseetheplacenta.Insomecultures,familiesburytheplacentainaspecialplace,suchastheirbackyards. Ifyouhavequestionsabouttheplacentaorplacentalproblemsduringpregnancy,talktoyourhealthcareprovider.Heorshecanhelpyoubetterunderstandtheplacenta'sroleduringyourpregnancy.   Thereisaproblemwith informationsubmittedforthisrequest.Review/updatethe informationhighlightedbelowandresubmittheform. GetthelatesthealthinformationfromMayoClinic’sexperts. Signupforfree,andstayuptodateonresearchadvancements,healthtipsandcurrenthealthtopics,likeCOVID-19,plusexpertiseonmanaginghealth. Email ErrorEmailfieldisrequired ErrorIncludeavalidemailaddress LearnmoreaboutMayoClinic’suseofdata. Toprovideyouwiththemostrelevantandhelpfulinformation,andunderstandwhich informationisbeneficial,wemaycombineyouremailandwebsiteusageinformationwith otherinformationwehaveaboutyou.IfyouareaMayoClinicpatient,thiscould includeprotectedhealthinformation.Ifwecombinethisinformationwithyourprotected healthinformation,wewilltreatallofthatinformationasprotectedhealth informationandwillonlyuseordisclosethatinformationassetforthinournoticeof privacypractices.Youmayopt-outofemailcommunicationsatanytimebyclickingon theunsubscribelinkinthee-mail. Subscribe! Thankyouforsubscribing OurHousecalle-newsletterwillkeepyouup-to-dateonthelatesthealthinformation. Sorrysomethingwentwrongwithyoursubscription Please,tryagaininacoupleofminutes Retry ShareTweet March25,2020 Showreferences RobertsV,etal.Placentaldevelopmentandphysiology.https://www.uptodate.com/contents/search.AccessedFeb.6,2020. LockwoodCJ,etal.Placentaprevia:Epidemiology,clinicalfeatures,diagnosis,morbidityandmortality.https://www.uptodate.com/contents/search.AccessedFeb.6,2020. HartHayesE.Placentophagy,lotusbirthandotherplacentapractices:Whatdoestheevidencetellus?TheJournalofPerinatalandNeonatalNursing.2019;doi:10.1097/JPN.0000000000000402. CunninghamFG,etal.,eds.Obstetricalhemorrhage.In:WilliamsObstetrics.25thed.McGraw-HillEducation;2018.https://accessmedicine.mhmedical.com.AccessedFeb.6,2020. ResnikR,etal.,eds.Placentapreviaandaccreta,vasaprevia,subchorionichemorrhageandabruptioplacentae.In:CreasyandResnik'sMaternal-FetalMedicine:PrinciplesandPractice.8thed.Elsevier;2019.https://www.clinicalkey.com.AccessedJune6,2020. WickMJ,ed.Managingmom'shealthconcerns.In:MayoClinicGuidetoaHealthyPregnancy.2nded.MayoClinic;2018. MooreKL,etal.Placentaandfetalmembranes.In:TheDevelopingHuman:ClinicallyOrientedEmbryology.11thed.Elsevier;2020.https://www.clinicalkey.com.AccessedFeb.6,2020. MartinRJ,etal.,eds.Placentalpathology.In:FanaroffandMartin'sNeonatal-PerinatalMedicine:DiseaseoftheFetusandInfant.11thed.Elsevier;2020.https://www.clinicalkey.com.AccessedFeb.6,2020. WeeksA.Retainedplacentaaftervaginalbirthandlengthofthethirdstageoflabor.https://www.uptodate.com/contents/search.AccessedFeb.7,2020. LandonMB,etal.,eds.Placentaaccretaspectrum.In:Gabbe'sObstetrics:NormalandProblemPregnancies.8thed.Elsevier;2021.https://www.clinicalkey.com.AccessedMarch6,2020. Frequentlyaskedquestions:PregnancyFAQ038:Bleedingduringpregnancy.AmericanCollegeofObstetriciansandGynecologists.https://www.acog.org/Patients/FAQs/Bleeding-During-Pregnancy.AccessedFeb.6,2020. ArachchillageDRJ,etal.Inheritedthrombophiliaandpregnancycomplications:Shouldwetest?SeminarsinThrombosisandHemostasis.2019;doi:10.1055/s-0038-1657782. 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