A GnRH (gonadotropin‑releasing hormone) stimulation test assesses pituitary function of the reproductive axis. After giving synthetic GnRH, blood is sampled at set intervals to measure LH and FSH responses. It helps diagnose causes of delayed or precocious puberty, amenorrhea, infertility or hypogonadism and distinguishes pituitary from hypothalamic disorders or functional versus organic reproductive‑axis problems.

Costs vary by country, facility and insurance. On public health systems the GnRH stimulation test is usually covered at no charge. In private settings it commonly ranges from about $200–$1,500 in the United States and roughly ₹1,500–8,000 in India for the drug plus serial blood draws and lab analysis. Check with your clinic or insurer for exact pricing.

When gonadotropin‑releasing hormone (GnRH) is high in a pulsatile pattern, the pituitary increases luteinizing hormone (LH) and follicle‑stimulating hormone (FSH), boosting sex steroid production (estrogen, progesterone, testosterone) and gametogenesis. Conversely, continuous sustained high GnRH desensitizes pituitary receptors, suppressing LH/FSH and lowering sex steroid levels — a mechanism used therapeutically.

Common side effects of the GnRH stimulation test include injection-site pain, flushing, headache, nausea, lightheadedness, sweating, and transient changes in heart rate or blood pressure. Less commonly, vomiting, palpitations, fainting, allergic reactions (rash, swelling) or brief mood changes can occur. These effects are usually mild and short-lived; seek urgent care for breathing difficulty, chest pain, severe swelling, or prolonged fainting.

Low GnRH reduces pituitary LH and FSH release, causing low sex hormones (testosterone or estrogen). This can lead to delayed or absent puberty, irregular or absent periods, reduced libido, infertility, hot flashes, lower bone density, muscle loss, fatigue and mood changes. Treatment targets the underlying cause and may include hormone replacement or gonadotropin therapy.

A gonadotropin blood test measures pituitary hormones—luteinizing hormone (LH) and follicle‑stimulating hormone (FSH), and sometimes human chorionic gonadotropin (hCG)—to evaluate reproductive and pituitary function. It helps diagnose infertility, menstrual irregularities, puberty timing, menopause, or suspected hypogonadism. A small blood sample is taken; results vary by sex, age and menstrual phase—high levels suggest primary gonadal failure, low levels indicate hypothalamic/pituitary causes.