Placental lactogen, also referred to as chorionic somatomammotropin, is a polypeptide hormone, produced by the placenta during pregnancy.
[1] Classified within the somatotropin family, placental lactogen shares both structural and functional similarities to growth hormone and pituitary prolactin.
[2] It has been identified in various mammals, including humans, monkeys, mice, cows, hamster, and sheep.
[3] Similarly, bovine placental lactogen exhibits diversity, through its molecular forms rather than secretion timing, with multiple isoforms differing in molecular weight and charge due to variations in glycosylation and truncated transcripts.
[2] While there are many shared characteristics, placental lactogen is synthesized by distinct trophoblast cell types.