noun, plural: placental growth hormones
A polypeptide hormone produced and secreted from the placenta during pregnancy, and that essentially promotes growth in humans and other animals
A growth hormone (GH) is one of the hormones produced by an endocrine gland. It is a polypeptide that, in essence, promotes a wide range of activities in the body which stimulate growth. Generally, this will involve promoting protein synthesis, while the hormone also promotes the lengthening of bones, which in turn helps to provide support for the future growth of the organism. Growth hormones may be produced by the pituitary gland and by the placenta.
The growth hormone produced from the placenta is called placental growth hormone (PGH) or growth hormone variant as opposed to the pituitary growth hormone secreted by the pituitary gland. It belongs to the somatotropin/prolactin family of hormones and becomes the predominant form of growth hormone in the body during pregnancy. In humans, PGH is encoded by the GH2 gene on chromosome 17. Mutation in this gene may lead to the deficiency in placental growth hormone or lactogen.