I-placental somatomammotropin (i-lactogen) ikhutshwa ngexesha lokukhulelwa kuphela nge-placenta. Kwabesetyhini nabasetyhini abakhulelweyo, akukho i-lactogen ye-placental ejwayelekile. Le hormone ye peptide, efana nesakhiwo kwiprolactin ye-pituitary gland, kodwa iyasebenza kakhulu. Ngaphantsi kwempembelelo yalo, ukukhula komzimba kunye nokulungiswa kweengcambu ze-mammary zokuvelisa ubisi kwenzeka. Kwaye, njengeprolactin, inomphumela oshukumisayo kumzimba ophuzi weeve. Ngaphantsi kweempembelelo ze lactogen, ivelisa i-progesterone, eqinisekisa ukugcinwa kokukhulelwa de iiveki ezili-16.
Kwimiqathango eyahlukeneyo yokukhulelwa i-placenta ivelisa i-lactogen ye-placental ngexabiso elithile:
- iqalisa ukumiselwa kwiiveki ezili-10;
- ubuninzi bufikelela kwiiveki ezingama-38;
- ukuya kwiiveki ezingama-40 kuyancipha ngenxa yokuguga kwepalacenta.
Isantya se-lactogen eplastiki ngexesha lokukhulelwa kwithuba elithile lichazwe ngetafile.
Isilingo se-lactogen sepencental senziwa njani?
Ukufundwa kwe-lactogen ye-placental, igazi lithathwa kusasa, kwisisu esingenalutho, kwisisu somfazi okhulelwe, kuba i-90% yobungakanani bayo ingena egazini legazi kwaye i-10% kuphela e-fetal fluid. Iimpawu zokuhlalutya:
- ukuxilongwa kwe-placenta ngexesha lokukhulelwa (kunye ne-estradiol yamahhala);
- ukuxilongwa kwe-bladder skidding kunye ne-chorion carcinoma (ukwehla kwinqanaba le lactogen ephahleni kwizinga eliphezulu le-griadotropin).
Kwimeko yokufa kwe-fetus, ukukhulelwa okukhenkce, ukungasebenzi kweplantshi, ukukhulelwa kokulibaziseka, ukukhulelwa kwexesha lokukhulelwa kwe-fetal, ukukhulelwa kwexesha lokutsalwa kwe-gestosis, ukwehla kwinqanaba le-lactogen eliphambili liya kugcinwa. Kwaye ukwanda kwawo kunokwenzeka xa ukhulelwe , i-diabetes mellitus (kunye ne-placenta egxininisekile), i-Rh-conflict of mother and fetus, i-fetus macrosomia, i-trophoblast tumors.