Relaxin

Relaxin is a peptide hormone primarily produced during pregnancy by the corpus luteum, placenta and decidua in mammals. It has two primary functions: to loosen the ligaments of the pelvis, aiding in parturition (childbirth) and to increase the size of mammary glands, allowing nutrient-rich milk production. It has also been shown to play a role in heart development in some species. Outside of its physiological functions, relaxin has a range of research and medical uses including the study of cardiovascular, reproductive and musculoskeletal biology, to induce preterm labor, and even to treat erectile dysfunction in men.