Prolactin Blood Test

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Test Overview

A prolactin test measures the level of the hormone, Opens dialog prolactin, which is made by the pituitary gland, Opens dialog, in your blood.

Pregnant women have high levels of prolactin, which helps make breast milk. During pregnancy, prolactin levels increase by 10 to 20 times. After the baby is born, prolactin stays high if you are breastfeeding. In women who do not breastfeed, prolactin levels return to normal soon after they give birth. After months of breastfeeding, prolactin levels may also return to normal levels even if you still breastfeed.

The pituitary glands of men and nonpregnant women also make prolactin but it is not clear what it does in the body for these people.

Prolactin levels are different throughout the day. The highest levels occur during sleep and shortly after you wake up. Prolactin levels also get higher during times of physical or emotional stress.

Many medicines can cause prolactin levels to go up. Tumors of the pituitary gland can sometimes cause prolactin to be made. A damaged pituitary gland may not be able to make normal amounts of prolactin so levels will be lower.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

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