LH (Luteinizing Hormone)

Luteinizing hormone is a protein produced by the pituitary gland. Luteinizing hormone helps regulate the menstrual cycle and egg production in women. An increase in luteinizing hormone levels about midway through the menstrual cycle (day 14 of a 28-day cycle) causes ovulation. In men, luteinizing hormone stimulates the production of testosterone.

Luteinizing hormone deficiency is a condition that almost occurs in conjunction with follicle stimulating hormone (FSH) deficiency because both are produced by the pituitary gland. Luteinizing hormone deficiency can manifest in both women and men as developmental or reproductive problems that can be anywhere from subtle to serious.