Inhibin A blood test
Quick answer: An inhibin A test measures a hormone made by the placenta in pregnancy and by the ovaries. It is mainly used in the quadruple marker test in the second trimester to estimate the chance of Down syndrome in the baby.
- SampleBlood
- TakesAbout 5 minutes
- Before the testNo special preparation is usually needed.
- In fertility careInhibin A is part of second-trimester screening, which gives a risk figure, not a diagnosis.
How the test is done
- 1You share your dating scan so the exact week is known
- 2The skin over a vein is cleaned
- 3A needle draws blood into a tube
- 4The result is combined with AFP, hCG and estriol
What your results can mean
Reading your report
The result is read against the exact week of pregnancy, so discuss it with your doctor.
If the result is outside the usual range
In pregnancy, a high level can be seen with a higher chance of Down syndrome, and sometimes with placenta problems. The result is a screening chance, not a diagnosis.
Who usually has this test
Pregnant women in the second trimester, usually around 15 to 20 weeks, having quadruple marker screening.
Risks and aftercare
There is no risk to the baby from this blood test.
Names and options
Also called: inhibin A
Listed by the hospital as
- INHIBIN A, SERUM
Questions about this test
What is the quadruple marker test?
It is a second-trimester screening blood test that combines AFP, hCG, estriol and inhibin A to estimate the chance of some conditions.
How is inhibin A different from inhibin B?
Inhibin A is mainly used in pregnancy screening. Inhibin B comes from developing follicles and testes and is used in fertility checks.
What happens after a high-chance result?
Your doctor may suggest a detailed scan, cell-free DNA testing or amniocentesis. These help give a clearer answer.
Related tests
Tamara Hospital & IVF Centre, Rajajinagar
34/3, 10th Cross Road, opp. Vardhaka Sardar Patel School, 1st N Block, 2nd Stage, Rajajinagar, Bengaluru 560010
The hospital is open 24 hours. Call before you come to check the timing for your scan or sample collection.
Get directions ↗IVF Pulse fertility care at Tamara Hospital →
Reception
Waiting area
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This page explains each test in general terms so you know what to expect. It is not medical advice: your doctor decides which tests you need and what your results mean. Reference ranges differ between laboratories. Updated 4 November 2026.