INHIBIN A Detail

Inhibin A is a hormone produced by the placenta during pregnancy and by the ovaries in non-pregnant women. It plays a role in regulating follicle-stimulating hormone (FSH) secretion from the pituitary gland.

The Inhibin A test is most commonly used in two clinical contexts:

1. Maternal Serum Screening (During Pregnancy):

Inhibin A is part of the quadruple marker screening test (along with AFP, hCG, and estriol), usually performed between 15–20 weeks of gestation. Elevated levels of Inhibin A in maternal serum may be associated with:

• Increased risk of Down syndrome (Trisomy 21),

• Preeclampsia,

• Preterm birth or other pregnancy complications.

2. Evaluation of Ovarian Function and Tumors:

Inhibin A is also used as a tumor marker for:

• Granulosa cell tumors and other sex cord-stromal tumors of the ovary,

• Monitoring for recurrence or treatment response in these cancers.

In postmenopausal women, elevated Inhibin A levels may indicate an ovarian tumor, since normal levels are typically low.