Inhibin A

The Inhibin A is a simple blood test used to measure the level of inhibin A, a hormone primarily produced by the ovaries in women and by the placenta during pregnancy. It helps in the diagnosis of Granulosa cell tumors and Mucinous Epithelial Ovarian Tumor. Also, it is done in pregnant women to assess the risk of certain chromosomal abnormalities like Down’s syndrome in the growing baby.

Inhibin A plays an important role in regulating the production of follicle stimulating hormone (FSH) and is involved in the feedback mechanism of the reproductive system in women. The levels of Inhibin A are often measured in blood to assess ovarian function, evaluate fertility ,and screen for certain chromosomal abnormalities during pregnancy. 

In non-pregnant women, the Inhibin A test can be used to evaluate ovarian function and diagnose certain reproductive problems including, the assessment for ovarian reserve, an important indicator for fertility evaluation. Additionally, elevated levels of Inhibin A can be a marker for certain types of ovarian cancer , particularly granulosa cell tumors and mucinous epithelial ovarian cancers. This test is used in conjunction with other lab tests to help diagnose ovarian cancer and monitor the progression or recurrence of the cancer. 

In pregnant women, the Inhibin A test is often done as a part of maternal prenatal screening, known as the quadruple screening test. It is done between the 14th and 22nd weeks of gestation (ideal 15-20 weeks i.e., second trimester) of pregnancy. It helps assess the risk of the growing baby (fetus) having chromosomal abnormalities such as Down’s syndrome (trisomy 21), Edward’s syndrome (trisomy 18). Elevated levels of Inhibin A may indicate an increased risk of these conditions in the fetus, warranting further investigation or diagnostic testing. However, an increased risk does not mean that the baby is affected, and further tests must be performed before a confirmed diagnosis can be made.

No special preparation is required for this test. However, a pregnant woman needs to be prepared to provide informed consent before undertaking this test. The laboratory personnel will explain the purpose, benefits, and limitations of this test. 

Lab test results vary across laboratories. Abnormal test results require expert interpretation; therefore , don't self medicate at home solely based on these results and always consult a doctor for proper understanding of the test results. The insights from this test will help the doctor correlate clinical and laboratory findings and tailor an appropriate treatment plan.