What Is An Inhibin B Test?
The Inhibin B test is a blood test that measures the levels of Inhibin B, a hormone produced in the ovaries (in women) and testes (in men). This hormone plays a crucial role in regulating reproductive functions.
In women, Inhibin B is produced by ovarian follicles and helps control follicle-stimulating hormone (FSH) secretion. The test is often used to assess ovarian reserve (egg supply) in women experiencing fertility issues. Low levels may indicate diminished ovarian reserve or conditions like premature ovarian failure.
In men, Inhibin B is produced by Sertoli cells in the testes and reflects sperm production. The test helps evaluate testicular function, especially in cases of infertility or disorders like azoospermia (absence of sperm).
Doctors may also order this test for children with delayed or precocious puberty to assess gonadal function.
How is the Test Performed?
Sample Collection
A blood sample is taken from a vein in the arm.
Testing Process
The sample is sent to a lab, where an immunoassay (such as ELISA) measures Inhibin B levels.
Results
Reports are normally available in 7 to 12 days.
What are the symptoms that prompt this test?
In Women
- Difficulty conceiving
- Irregular or absent periods
- Symptoms of early menopause (hot flashes, vaginal dryness)
- Suspected polycystic ovary syndrome (PCOS)
In Men
- Low sperm count or infertility
- Undescended testicles (in children)
- Delayed puberty in boys
In Children
- Early or delayed puberty
- Abnormal genital development
What are Normal Ranges for This Test?
Women
Premenopausal – 10–140 pg/mL (varies with menstrual cycle)
Postmenopausal – <5 pg/mL
Men – 100–400 pg/mL
Children – Varies with age and puberty stage
** Normal levels are dependent on a number of factors including age, gender, testing method and health condition of patient etc. Result interpretation should be done by a qualified doctor or healthcare professional.**
What Happens if Test Results Show Abnormal Levels?
For Women – Low levels may suggest diminished ovarian reserve. Further tests like AMH (Anti-Müllerian Hormone) or FSH may be needed.
For Men – Low levels may indicate impaired sperm production. A semen analysis or genetic testing may follow.
For Children – Abnormal levels may require hormone tests or imaging to assess puberty disorders.
Additional Information About Inhibin B Test
When to Seek Medical Attention
If experiencing infertility, irregular periods or delayed puberty, contact your doctor immediately.
Related Tests
- FSH
- AMH
- Testosterone
- Estradiol
- Semen analysis
Conditions Affecting Results
- PCOS
- Ovarian tumors
- Chemotherapy
- Testicular damage
