I-placenta yenziwa ngolu hlobo lulandelayo: iqanda elinomsolo, ukungena kwisigxina se-uterine, lufakwe eludongeni lwayo, luya kwi-membrane, "njengobhola obushushu kwioli." Kuwo onke macala iqanda lijikelezwe ngumbumba womlenze wesibeleko kwaye londla ngokukhupha izondlo ngokusebenzisa iimbumba zeqanda lomntwana. Emva kweentsuku ezili-9 kwiigobolondo zangaphandle zeqanda le-fetal zikhona i-villi, ezingena kwi-membrane ye-uterus, kwaye sele sele ihamba kunye nayo izondlo ziya kwisiqhamo.
Emva koko, loo nxalenye ye-villi, ejongene nodongeni lwesisu, yenza i-placenta kwaye iphinde ifikelele kwisiseko se-muscular ye-uterus. Kodwa phakathi kwe-villi kunye nodonga lwesisu, kukho indawo apho igazi lijikeleza khona-nantsi kukho utshintshi lwe-oksijini, i-carbon dioxide, izondlo ezivela kumama ukuya kumntwana kunye nomva.
Njengoko ukukhulelwa kuqhubeka, i-placenta iyakhula. Ngoku i-compact, idense, ithatha ifom ye disk. Elinye lamacala alo liphendukele kumntwana, intambo yomhlaba iphuma kwindawo, apho imithwalo yegazi ikhona. Kule mikhumbi, izondlo, i-oksijini zingena kumntwana, kunye nemveliso yalo msebenzi obalulekileyo ungena kwigazi lomama. Ngalinye icala kwicala, umama, uqhotyoshelweyo eludongeni lwesisu.
Njengoko ubona, i-placenta ithatha indawo yengane enezimbini ezibalulekileyo ezibalulekileyo: imiphunga, isisu, izintso, njl. Umntwana unokuhlakulela ngokuqhelekileyo kuphela ukuba i-placenta isebenza ngokufanelekileyo. Oogqirha bomzimba womama wesikhathi esizayo bayadibanisa kunye ne-placenta kunye nosana kwinkqubo enye ye "mother-placenta-fetus". Umlinganiselo wale nkqubo ukhulu kakhulu, ummandla wayo ungama-9 m 2 , kunye nenethiwekhi yemithambo yegazi ingama-40-50 km ubude! Ubungakanani be-placenta ngu-3-4 cm, ekupheleni kokukhulelwa ubunzima bayo buyi-500-600 g.
I-placenta yomntu isebenza njengesithintelo, ayivumeli izinto ezinobungozi kunye neenqwelo ezichaphazelekayo zidlulisela umntwana, kodwa, ngelishwa, izixhobo zeekhemikhali zamanye amayeza unina kunye namaxesha athile abangela ukusulela. I-placenta ivelisa inani lee-hormone kunye nezinye izinto ezisebenzayo ezixhasa ukukhula kokukhulelwa nokukhula komntwana.
I-placenta inomphumo onenzuzo kumzimba womama wesikhathi esizayo, ekugqibeleni ininzi yamahomoni ayinceda ukuba ivumelane nokukhulelwa, ithatha inxaxheba kwinkqubo yokuqalisa umsebenzi. Kungoko, xa bebukele umama ozayo, oogqirha baqwalasela ngokukodwa ukubonakala kunye nesakhiwo se-placenta ngexesha lokukhulelwa. Ukuhlolwa kwe-ultrasound, ingqalelo ye-placental iyahlawulwa, okokuqala, kwindawo yokuqhotyoshelweyo. Ngokuqhelekileyo itholakala ngaphantsi kwesibeleko okanye kwenye yeendonga zayo. Kodwa ngamanye amaxesha i-placenta ingafakwa kakhulu kufuphi nomlomo wesibeleko. Oku kunokukhokelela ekubeni emva koko kuya kwehla, kwindawo ye-pharynx yangaphakathi yomlomo wesibeleko, ewugubungele ngokupheleleyo (iplascenta previa) okanye nxalenye (i-placenta previa).
Ngokuphuhliswa kwepentecenta previa, ukuzalwa kwemvelo akunakwenzeka - kwicandelo le-caesarean kuphela. Oku akufanelekanga. Ngethuba lethu, usebenzo lwenziwe ngekhwalithi, ngaphandle kwemiphumo yomama nosana. Ngendlela, umsebenzi awuyi kufunwa. Ngamanye amaxesha, ngokunyuka kokukhulelwa, i-placenta, ngokuchaseneyo, iyakhula ngokukhawuleza ibe yindawo eqhelekileyo. Ubuninzi be-Placenta buyisongela ukuphuma kwegazi ngexesha lokukhulelwa, ukukhipha isisu, ukuzalwa ngaphambi kokuzalwa.
Kwi-ultrasonography, ingqwalasela ye-placental ihlawulwa kwakhona kwi-thickness. Ukugqithisa ubungakanani obuvumelekile kunokuthetha ukuvuvukala kwe-placenta, eyenzekayo kunye ne-Rh-conflict, isifo sikashukela, ubukho bentsholongwane, ukungalunganga komntwana, gestosis enkulu. Ukunciphisa ngobukhulu kubonisa ukungenakulungeleka kwamaplahla. Kukho nawuphi na, kuyimfuneko ukuthatha amanyathelo okuphucula ukusebenza kweplascent ukuze kuqinisekiswe uphuhliso oluqhelekileyo lomntwana. Kubaluleke ngokukhethekileyo ukufumanisa ukuphuhliswa, ukukhula kwipentecenta ngamaxesha ahlukeneyo okukhulelwa. Ukuba i-placenta iqala ukuvuthwa kakhulu kusasa, sele ibonisa isongelo sokukhupha isisu.
Ngokukhawuleza xa usana luzalwa, kwaye ugqirha unqumla intambo yomthi, imisebenzi yomgca we-placenta, kwaye ingaphantsi kwemizuzu engama-30 yesithathu, isigaba sokugqibela sokubeletha senzeke-ukuzalwa kwepentecenta kunye nezibilini (emva kokuzalwa). Emva koko, i-placenta ihlolwe ngokucophelela - ngaba kukho naziphi na iziphoso, i-lobules eyongezelelweyo, iifomati zokubala (kubalwa), ebonisa ukuba umntwana esibelethweni ahlupheke ngokwaneleyo. Eli qiniso kufuneka lixelelwe kwinqanaba labantwana. Emva kwakho konke, ngenxa yomntwana, ulwazi olunjalo luphawu lwakhe lokuqala lwempilo okanye uphawu lokuqala lwezilwanyana ezinokwenzeka. Ukuba kukho i-defect kwi-placenta, ukukhusela i-uterine yegazi, i-anesthesia isusa i-aseesthe ye-placenta ukusuka kwisibeletho.
Ngoko, i-placenta yomntu, malunga nesakhiwo, uphuhliso, imisebenzi, ngoku uyazi ukuba lilungu lesigxina kodwa elibaluleke kakhulu elondla kwaye likhusela umntwana kwisibeleko somama. Emva kokuzalwa, i-placenta isenokutshatyalaliswa okanye isetyenziswe kwiinjongo zonyango okanye zesayensi.