Ekupheleni kwamasonto amane isithelo sakhula sibe yi-1 mm kanti ubukhulu bayo manje bunjengembewu ye-poppy. Kulesi sigaba sokuthuthukiswa, i-fetus evela eqanda lesibusane iqala ukuguqula ibe umbungu. Lapho ukhulelwa ngesonto eli-4 ubukhulu bezithelo nakuba bukhulu, kodwa umbungu uzwa ngokuzethemba futhi ngokuphindaphindiwe unamathele odongeni lwesibeletho.
Kusukela ngalesi sikhathi, inethiwekhi yezinsiza ikhiqizwa endaweni lapho umbungu ukhonjiswa khona odongeni lwe-uterine. Lezi zinkinga zixhuma umntwana ozayo nomama wakhe, futhi ngazo ngeke athole konke okudingekayo ekuphileni nasekuthuthukisweni. Uma u-fetus uneminyaka engamasonto ama-4, i-embryo iqala ukuthuthukisa izitho ezingezinye zegciwane, ukuhlinzeka ngokudla kwayo, ukuphefumula nokuvikelwa. Imizimba enjalo ihlanganisa:
- I-Chorion . I-membrane yangaphandle ye-embryonic ekhuthaza ukudala i-placenta, eyakhiwe ngokuphelele ekupheleni kweviki leshumi nambili.
- Amnion . I-cavity, okuyisigqila sesisu, iveza i-amniotic fluid, lapho umbungu ukhona khona.
- I-yolk sac . Kuze kube neminyaka engama-7 kuya kwangu-8, unesibopho se-hematopoiesis ye-embryo.
I-fetus ibonakala kanjani emavikini angu-4?
Abantu abaningi bayazibuza ukuthi ingane yakho ingamaviki amane. Phakathi nalesi sikhathi, kubonakala sengathi i-disk equkethe izingqimba ezintathu zamangqamuzana - izigaba zegciwane:
- i-ectoderm (ungqimba lwangaphandle), obangela ukubunjwa kwesikhumba, izinwele, isimiso sezinzwa, ama-lens kanye noqweqwe lwawo lwamazinyo;
- I-Endoderm (ungqimba ongaphakathi), obhekene nokubunjwa kwesistimu yokugaya, isibindi, i-thyroid ne-pancreas;
- i-mesoderm (ungqimba ophakathi), ekugcineni uguqukela emasendeni, izicubu ezixhumeneyo nemisipha, igazi kanye nesistimu ye-excretory, izitho zangasese.
Ukukhulelwa kuzobonakala kuphela ekupheleni kwesonto, uma kwenziwa ukuhlaziywa kwe-hCG. Ngokuqondene nokuhlolwa kwekhaya, akakwazi njalo ukuqaphela isikhathi esinjalo, ngoba umchamo wesifazane uqukethe inani elilinganayo lamahomoni.