I-somatomammotropin ye-placental (i-lactogen) ikhishwa ngesikhathi sokukhulelwa kuphela nge-placenta. Kubesifazane nabesifazane abangakhulelwe, akakho i-lactogen ephahleni ejwayelekile. Le hormone ye-peptide, efana nesakhiwo ku-prolactin ye-pituitary gland, kodwa isebenza kakhulu. Ngaphansi kwethonya laso, ukuvuthwa nokulungiswa kwezinhlayiya ze-mammary zokukhiqiza ubisi kwenzeka. Futhi, njengeprolactin, inomthelela omuhle emzimbeni ophuzi wama- ovari. Ngaphansi kwethonya lama-lactogen, likhiqiza i-progesterone, eqinisekisa ukugcinwa kokukhulelwa kuze kube amasonto angu-16.
Ngezimiso ezehlukene zokukhulelwa i-placenta ikhiqiza i-lactogen ye-placental ngamanani ahlukene:
- iqala ukunqunywa kusuka emavikini ayishumi;
- ukuphakama kufinyelela emavikini angu-38;
- Amasonto angama-40 ancipha ngenxa yokuguga kwe-placenta.
Isilinganiso se-lactogen ephansi lapho ukhulelwe isikhathi esithile sinqunywa ithebula.
Isilingo se-lactogen esenziwe nge-placental senziwa kanjani?
Ukuze kuhlolwe i-lactogen ye-placental, igazi lithathwa ekuseni, esiswini esingenalutho, kusukela emthanjeni wesifazane okhulelwe, njengoba inani elingu-90% lingena egazini lika-wesifazane kanti kuphela u-10% kuphela osesiswini somswakama. Izinkomba zokuhlaziywa:
- ukuxilongwa kwe-placenta ngesikhathi sokukhulelwa (kanye ne-estradiol yamahhala);
- ukuxilongwa kwe-skidding ye-vesifire kanye ne-chorion carcinoma (ukwehla ezingeni le lactogen ephahleni kwizinga eliphezulu le-griadotropin ye-chorionic).
Uma kwenzeka ukufa kwe-fetus, ukukhulelwa okufriziwe, ukungasebenzi kahle kwe-placental, ukukhulelwa ukulibaziseka, ukukhulelwa kwe-fetal retardation syndrome, ukukhulelwa kwe-gestosis ekupheleni kwesikhathi, ukwehla kwezinga lactogen eliphansi kuyobanjwa. Futhi ukwanda kwawo kungenzeka uma kwenzeka ukhulelwe kaningi , isifo sikashukela mellitus (nge-placenta eqinisiwe), impikiswano ye-Rh yomama ne-fetus, i-fetus macrosomia, izicubu ze-trophoblast.