LH is a reproductive hormone. Stimulation of the ovaries or testes leads to the release of an egg from the ovary (ovulation) in women or the production of testosterone in men. The LH test measures the amount of luteinizing hormone in the blood. does?** In women of reproductive age, several hormones (LH, FSH, estrogen and progesterone) increase and decrease in a specific order during each menstrual cycle. The menstrual cycle of women is divided into two follicular and luteal phases, each phase lasting about 14 days. Near the end of the follicular phase, the L.H. cycle increases in the middle of the egg. In the luteal phase, where the ruptured egg follicle becomes the corpus luteum. LH stimulates the corpus luteum to start producing progesterone.... FSH and LH levels decrease, while progesterone and estradiol concentrations increase.... If the egg is not fertilized, these hormone levels in turn decrease as the days approach puberty. The result is a decrease in the amount of LH secreted.... **In infants and children,** LH levels rise shortly after birth and then decline to very low levels at 1-8 months in boys and 6-6 years of age.. At older ages, LH levels rise again before the onset of puberty and the development of secondary sexual characteristics... **In males and females**, LH testing is often used along with other tests (FSH, testosterone, estradiol, and progesterone) to help diagnose: - Cause of infertility - Pituitary disorders that can affect LH production.... - Conditions that affect the function of the ovaries or testicles.... **In women,** LH levels are useful for: - Check for irregular periods - Assessment of LH levels during the menstrual cycle ### **GNRH stimulation test:** In people with signs and symptoms of poor ovarian or testicular function, a gonadotropin-releasing hormone (GnRH) stimulation test may be performed. GnRH is a hormone produced by the hypothalamus that stimulates the pituitary gland to release LH and FSH. LH levels are measured. The hypothalamus (third), when LH surges in response to GnRH injections, helps. Puberty... Irregular timing of puberty may indicate a more serious problem with the hypothalamus, pituitary gland, ovaries or testes, or other systems. Measurement of LH and FSH can help distinguish between benign symptoms and true disease. Administration of GnRH indicates readiness of the pituitary gland for hormonal responses during puberty is....then more tests can be done to diagnose the main cause....> Kausar Pathobiology Specialist Laboratory is proud to have obtained ISO 9001, ISO 15189 and ISO 10002 in England, under the supervision of Dr. Dr. Dr. Ali Ayatollahi, a specialist in anatomy and clinical pathology, covers more than a thousand cases of various tests in the fields of pathology, genetics and clinical... > Address: Mashhad - Vakil Abad - Kausar Blvd. - between 2 and 4 Kausar - Farabi Doctors Building - negative One floor... Contact number: 04043-04048 051-38820202 and 09028840404