Luteinising hormone (LH) is produced by the pituitary gland in the brain. Control of LH production is a complex system involving hormones produced by the gonads (ovaries or testes) and the hypothalamus, such as gonadotrophin-releasing hormone (GnRH). Women’s menstrual cycles are divided into 2 phases, the follicular and luteal, by a mid-cycle surge of follicle-stimulating hormone (FSH) and LH. The high level of LH (and FSH) at mid-…Luteinising hormone (LH) is produced by the pituitary gland in the brain. Control of LH production is a complex system involving hormones produced by the gonads (ovaries or testes) and the hypothalamus, such as gonadotrophin-releasing hormone (GnRH). Women’s menstrual cycles are divided into 2 phases, the follicular and luteal, by a mid-cycle surge of follicle-stimulating hormone (FSH) and LH. The high level of LH (and FSH) at mid-cycle triggers ovulation (release of the egg from the ovary). LH also stimulates the ovaries to produce other hormones, mainly oestradiol and progesterone. Oestradiol helps the pituitary gland to control the production of LH. At the time of the menopause, the ovaries stop functioning and LH concentrations rise. In men, LH stimulates the Leydig cells in the testes to produce testosterone. LH concentrations are relatively constant in men after puberty. In infants and children, LH rises shortly after birth and then falls to very low levels (by 6 months in boys and 1-2 years in girls). At about 6-8 years, levels again rise with the beginning of puberty and the development of secondary sexual characteristics such as pubic hair, deepening voice in males and pubic hair and breast development in girls. How is the sample collected for testing? A blood sample is taken by needle from a vein in the arm. Is any test preparation needed to ensure the quality of the sample? No test preparation is required, but woman’s sample should be collected at specific times during her menstrual cycle usually during the first phase. See MoreSee Less
