A Prolactin Test for Irregular Periods: What a High Result Can Mean

Seeing a high hormone result before anyone has explained it can leave you searching for an answer. Take the report to the clinician who ordered it and ask what they recommend next. Bring your period dates and the questions you want answered about that particular result.

A high result has several possible explanations

Pregnancy and breastfeeding normally raise prolactin. Medicines and conditions such as an underactive thyroid can also raise it. Small increases can occur with stress or exercise, so a clinician may recommend repeat testing.¹

Tell the clinician about pregnancy or breastfeeding, your full medication list and supplements. Ask which possible explanations they are checking and whether another blood sample is part of the plan. Keep the original report so you can compare the next result with the same units and laboratory information.

A prolactinoma requires further assessment

A prolactinoma is a noncancerous pituitary tumor that produces prolactin. It can cause irregular or absent periods and milky breast discharge. Blood testing measures the hormone; imaging, usually MRI, helps confirm a suspected tumor and establish its size and location.²

Ask whether the findings so far warrant imaging or further blood tests, and who will explain those results. Mention any breast discharge, headaches or vision changes you want assessed. Write down whether a specialist referral is planned and how you will hear about the appointment.

Preparation comes from the team ordering the test

Prolactin varies through the day, and preparation may include instructions about timing or fasting. Medicines and vitamins can affect the result. MedlinePlus¹ advises checking with the clinician before stopping any medicine.¹

Ask for the instructions for your sample, including when to attend and whether you should eat beforehand. If you already had the test without receiving preparation instructions, explain that when discussing the result. Ask whether it changes the next step.

Leave with a follow-up plan

Before the conversation ends, confirm who will contact you, what happens if the level remains high, and whom you should call if you have not received the expected result. Request a copy of the plan to keep with your report.

Period, Handled includes a Period Scorecard and visit script. Use them to organize cycle dates and the testing questions you want discussed. Explore the periods playbook.