Understanding prolactin levels: what they mean for your health

Your hormones can reveal a lot about what is happening inside your body. From changes in your menstrual cycle and fertility to sex drive, breast health, and overall wellbeing, even small hormonal shifts can have a noticeable impact. Prolactin is one of the hormones that often goes unnoticed, but it plays an important role in several body processes. Understanding what prolactin is, why levels may change, and when testing may be helpful can give you valuable insight into your health and help you take more informed next steps.

Table of Contents

• What are prolactin levels?
• What causes abnormal prolactin levels?
• How to check your prolactin levels at home
• Frequently asked questions about prolactin levels

What are prolactin levels?

Prolactin levels show how much prolactin is present in your blood. In general, prolactin levels are naturally low in men and in women who are not pregnant or breastfeeding, and much higher during pregnancy and breastfeeding. 

Typical reference ranges are often below 20 ng/mL for men, below 25 ng/mL for non-pregnant women, and around 80 to 400 ng/mL for people who are pregnant or breastfeeding, although ranges can vary between laboratories. 

Prolactin contributes to many bodily functions, but its two main roles are:

• Triggering the development of mammary glands within breast tissues

• Supporting lactation and breastfeeding

Source: Cleveland Clinic, 2024

What causes abnormal prolactin levels?

1. High prolactin levels

Many different factors can cause prolactin levels to become higher than normal:

• Tumors 

• Radiation therapy

• Certain medications: 

• Birth control pills

• Antipsychotics (e.g.  risperidone or haloperidol)

• Blood pressure medications (e.g. methyldopa or verapamil)

• Heartburn or GERD medications (H2 antihistamines)

• Antidepressants (e.g. tricyclic antidepressants and SSRIs)

• Estrogen therapy for menopause symptoms

• Anti-nausea medications

• Opioid pain relievers

• Underlying health conditions:

• Chest wall injuries (e.g. fractured ribs or breastbone)

• Chronic kidney disease

• Chronic liver disease

• Cushing disease

• Hypothyroidism

• Shingles, especially on the chest

• Polycystic ovary syndrome (PCOS)

• Seizures

• In some cases, no clear cause is found

Source: Cleveland Clinic, 2024 

2. Low prolactin levels

The causes of low prolactin level can be:

• Reduced pituitary gland function

Low prolactin may be noticed after childbirth if milk production is unexpectedly low.

Source: Cleveland Clinic, 2024

How to check your prolactin levels at home

Homed-IQ offers prolactin testing as part of the Hormone Test for Women and the Female Fertility Test, both of which measure prolactin alongside other important hormone markers. 

Checking your prolactin level at home is usually simple. First, order a home test online. Your test kit is delivered to your door with clear instructions and the materials needed to collect your sample. Depending on the test, this may involve a small finger-prick blood sample. After collecting your sample, you send it back to the laboratory using the return packaging provided. Your results are then analysed by a certified lab and made available securely online. Homed-IQ support is available to answer any questions you may have throughout the testing process.

Frequently asked questions about prolactin levels

What symptoms indicate abnormal prolactin levels?

Symptoms of abnormal prolactin levels can differ from person to person:

• Irregular periods

• Absence of periods

• Breast milk production when not pregnant or breastfeeding

• Nipple discharge

• Infertility

• Erectile dysfunction or impotence

• Enlarged breast tissue in men

• Decreased facial or body hair

• Low sex drive

• Headaches

• Low bone mass

• Vision changes

• Low levels of other pituitary hormones, such as thyroid hormones or cortisol

Always consult a healthcare professional for diagnosis and treatment. 

Source: MedlinePlus, 2024; Cleveland Clinic, 2024 

Can stress or lifestyle affect prolactin levels?

Yes, besides the above mentioned causes, prolactin can also rise temporarily because of:

• Physical stress

• Exercise

• Eating a meal

• Sexual intercourse

• Nipple stimulation unrelated to breastfeeding

For long-term hormone health, prioritise a healthy lifestyle that includes regular sleep, stress management, balanced nutrition, and physical activity, and consult a healthcare professional if you have questions or ongoing concerns.

Source: Cleveland Clinic, 2024