What is Prolactin?
Prolactin is a hormone that originates in the pituitary gland. During and after pregnancy, the hormone stimulates the production of breast milk. It also plays an important role in menstruation, fertility and sex drive. Both men and women have prolactin in their blood, but the function in males is not yet fully understood.

Normal Value Range

• Negative Pregnancy Adult: 0 to 20 ng/mL or 0 to 20 µg/L or 0 to 859 pmol/L
• Pregnancy Trimester One: 36 to 213 ng/mL or 30 to 213 µg/L or 1565 to 9261 pmol/L
• Pregnancy Trimester Two: 110 to 330 ng/mL or 110 to 330 µg/L or 4783 to 14347 pmol/L
• Pregnancy Trimester Three: 137 to 372 ng/mL pr 137 to 372 µg/L or 5957 to 16174 pmol/L

Doctors may suggest a prolactin test if a female patient is experiencing reduced sex drive, irregular periods or breast milk production not associated with pregnancy or child birth. If a pituitary gland tumor is suspected, a prolactin test will also be ordered as part of a series of blood tests.

Men suffering from decreased libido or impotence may have abnormal prolactin levels.

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