Prolactin
Prolactin is a hormone produced by the pituitary gland that is best known for stimulating breast milk production. It also plays a role in reproductive health and immune function.
Category: Hormones
Also known as: prolactin, prl, serum prolactin, Lactotropic hormone, Mammatropic hormone, prolaktin
Reference range: 4–15.2 ng/mL (Source: ABIM)
Standard unit: ng/mL
High values may indicate
High prolactin levels (hyperprolactinemia) may indicate a pituitary adenoma (prolactinoma), hypothyroidism, kidney disease, liver disease, or certain medications (antipsychotics, antidepressants), and can cause irregular periods, infertility, and galactorrhea.
Low values may indicate
Low prolactin levels are uncommon and may indicate hypopituitarism or Sheehan syndrome (postpartum pituitary necrosis).
Frequently asked questions
- What is a normal Prolactin level?
- A typical reference range for Prolactin is 4–15.2 ng/mL (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is Prolactin measured in?
- Prolactin is most commonly reported in ng/mL. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do Prolactin reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track Prolactin over time?
- Yes. Upload results from any lab and BloodId charts your Prolactin over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: MedlinePlus, U.S. National Library of Medicine
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