Description
LH is a hormone released by the pituitary gland in response to luteinizing hormone- releasing hormone (LHRH) secreted by the hypothalamus. In concert with the other pituitary gonadotropin follicle stimulating hormone (FSH), it controls the length and sequence of the female menstrual cycle, including ovulation, preparing the uterus for implantation of a fertilised egg, and ovarian production of both oestrogen and progesterone. In males, it stimulates the Leydig cells in the testes to produce testosterone.
Indications
Persistently high LH levels are indicative of situations where the normal restricting feedback from the gonad is absent, leading to pituitary production of both LH and FSH. While this is typical in menopause, it may be abnormal in the reproductive years., where it may be a sign of premature menopause ,gonadal dysgenesis, Turner syndrome, castration, Swyer syndrome, certain forms of Congenital Adrenal Hyperplasia and testicular failure. Diminished secretion of LH can result in failure of gonadal function (hypogonadism). This condition typically manifests in males as failure in production of normal numbers of sperm. In females, amenorrhea is commonly observed. Conditions with very low LH secretions include Kallmann syndrome, hypothalamic suppression, hypopituitarism, eating disorder, hyperprolactinemia, gonadotropin deficiency and gonadal suppression therapy.
Sample Type, Quantity & Conditions
1 ml Serum 1 ml Li, Na, NH4+-Heparin, K3-EDTA, or Sodium Fluoride/Potassium Oxalate Plasma Stability: 14 Days at 2-8 °C 6 Months at -20 °C
Special Precautions
State day of cycle. Freeze only once.
Normal Range
Female Follicular Phase: 2.4 - 12.6 mIU/mL Female Ovulation Phase: 14.0 - 95.6 mIU/mL Female Luteal Phase: 1.0 - 11.4 mIU/mL Female Postmenopausal: 7.7 - 58.5 mIU/mL Male: 1.7 - 8.6 mIU/mL
