Placental somatomammotropin (lactogen) imatulutsidwa panthawi ya mimba yokha ndi placenta. Amayi ndi abambo omwe alibe amayi, palibe lactogen ya placental muyezo. Hamu yotchedwa peptide, yomwe imakhala yofanana ndi ma prolactin wa chifuwa, koma yogwira ntchito kwambiri. Pansi pa mphamvu yake, kusasitsa ndi kukonzekera mazira a mammary kuti apange mkaka amapezeka. Ndipo, monga prolactin, imakhudza thupi la chikasu la mazira ambiri. Mothandizidwa ndi placental lactogen, imatulutsa progesterone, yomwe imaonetsetsa kuti kusamalidwa kwa mimba kumapitirira mpaka masabata 16.
M'njira zosiyana za mimba, placenta imapanga lactogen yapakhungu yosiyana:
- imayamba kutsimikizika kuyambira masabata khumi;
- chiwombankhanga chikufikira masabata 38;
- Mpaka masabata 40 amachepa chifukwa cha ukalamba wa placenta.
Mlingo wa placental lactogen pa nthawi yoyembekezera kwa nthawi inayake umatsimikiziridwa ndi tebulo.
Kodi placental mayayiti akuyesa bwanji?
Kuphunzira pa placental lactogen, magazi amachotsedwa m'mawa, pamimba yopanda kanthu, kuchokera mu mitsempha ya mayi wapakati, popeza kuti 90% ya kuchuluka kwake imalowa m'magazi a mkazi ndipo 10 peresenti yokha ili mu fetal fluid. Zisonyezo za kusanthula:
- Kufufuza kwa placenta pa nthawi ya mimba (pamodzi ndi ufulu wa estradiol);
- matenda a chikhodzodzo ndi chorion carcinoma (kuchepa kwa mlingo wa lactogen pamatumbo a chorionic gonadotropin).
Ngati mwana wamwamuna akufa, ali ndi pakati, amatha kuchepetsa mimba, amayamba kuchepetsa matenda, kutenga mimba mochedwa, komanso kuchepa kwa lactogen. Ndipo kuwonjezeka kwake n'kotheka ngati pangakhale mimba yambiri , matenda a shuga (ali ndi mitsempha yowonjezera), mpikisano wa Rh ya amayi ndi fetus, fetal macrosomia, matumbo a trophoblast.