Luteinizing Hormone ( LH ) is a 42-kda heterodimer belonging to the glycoprotein hormone family. It is composed of non-covalently linked sugar chains and chains. The α subunit ( CGα ) is also a component of follicle stimulating hormone ( FSH ), thyroid stimulating hormone and chorionic gonadotropin. The unique β subunit gives the protein a specific biological role and is responsible for its interaction with its receptors )Luteinizing hormone is secreted by the anterior pituitary. Its secretion is controlled by gonadotropin-releasing hormone secreted by the hypothalamus ; however, luteinizing hormone secretion can also be stimulated by estradiol. Luteinizing hormone and FSH synergistically regulate female reproduction ; follicle stimulating hormone stimulates follicular growth, and luteinizing hormone induces ovulation. Luteinizing hormone also promotes the formation of corpus luteum by promoting the production of progesterone. In addition, luteinizing hormone is also thought to stimulate the adrenal glands of postmenopausal women and induce the secretion of dehydroepiandrosterone sulfate ( DHEA ), a precursor of androgens. In the testis, luteinizing hormone induces Leydig cells to produce testosterone. Excessive luteinizing hormone secretion has been shown to occur in women with polycystic ovary syndrome and is associated with an increased risk of infertility and miscarriage. In addition, elevated serum LH levels are associated with decreased cognitive ability and are associated with the development and progression of Alzheimer 's disease.