LEUTINISING HORMONE (LH)

Clinical significance

LH is a hormone secreted by the anterior pituitary gland. In women, LH is responsible for ovulation, stimulation of corpus luteum formation and stimulation of ovarian progesterone synthesis. In the late follicular phase, the increased amounts of estrogen exert positive feedback on the hypothalamus and pituitary resulting in a peak of LH and FSH. The LH surge is followed by rupture of the follicle and ovulation.

Clinical applications

• Prediction of ovulation: Rising LH levels anticipate impending follicle rupture.
• Diagnosis of ovulatory disorders

1. LH titers are chronically elevated in women with ovarian failure (and Menopause) along with FSH.
2. In polycystic ovarian disease, LH is released in excessive pulsatile bursts.
3. LH/FSH ratio is valuable predictive tool for ovarian hyperstimulation syndrome (OHS). Most OHS patients will have LH/FSH >1.
4. Work-up for a case of infertility.