Description
The LH (Luteinizing Hormone) and FSH (Follicle-Stimulating Hormone) blood test measures the levels of these two important pituitary hormones that regulate reproductive function in both men and women.
Purpose of the Test
- Assess fertility: Evaluates ovulation in women and sperm production in men.
- Diagnose menstrual or reproductive disorders: Helps determine causes of irregular periods, amenorrhea (absence of menstruation), or early/late puberty.
- Evaluate pituitary function: Abnormal levels may indicate pituitary gland disorders.
- Assess menopause or ovarian function: Helps confirm menopause or ovarian insufficiency.
- Investigate testicular function in men: Can indicate issues with testosterone production or spermatogenesis.
How LH and FSH Work
- LH: Triggers ovulation in women and stimulates testosterone production in men.
- FSH: Stimulates the growth of ovarian follicles in women and sperm production in men.
- Their levels fluctuate based on age, sex, menstrual cycle phase, and overall reproductive health.
Conditions Associated with Abnormal Levels
- High LH/FSH: Can indicate primary ovarian or testicular failure, menopause, or certain genetic conditions (e.g., Turner syndrome).
- Low LH/FSH: May suggest pituitary or hypothalamic dysfunction, hypothyroidism, or stress-related hormonal suppression.
- Imbalance between LH and FSH: Can point to polycystic ovary syndrome (PCOS) or other endocrine disorders.
How the Test is Performed
- Blood is drawn from a vein, usually in the morning.
- Women may have the test timed according to their menstrual cycle for more accurate interpretation (often day 3 of the cycle).
Fasting Not Required
This test is a key tool for evaluating reproductive health, hormonal balance, and fertility issues.