Prolactin is a hormone produced and secreted by the pituitary gland - a small gland located at the base of the brain. It plays several important roles in the female body, particularly in relation to reproduction and lactation.
Read on, to learn more about prolactin, its purpose, the symptoms related to high and low levels, and what you can do to balance prolactin levels.
What Is the Purpose of Prolactin in The Body?
Prolactin is primarily produced by the pituitary gland, which is a small gland at the base of the brain. However, the central nervous system, immune system, uterus, and mammary glands can also produce small amounts of prolactin during exercise, stress, or stimulation.
Largely responsible for breast tissue development, mammary glands, and lactation, prolactin also contributes to many other bodily functions such as immune regulation and influencing the menstrual cycle.
What Are Normal Prolactin Levels?
Normal prolactin levels will vary slightly from woman to woman, but generally measure less than 25ng/mL in women who are not pregnant or breastfeeding. For women who are pregnant or breastfeeding, a normal range typically measures 80-400 ng/mL.
How Prolactin Levels Fluctuate
Prolactin During & After Pregnancy
When women are pregnant, normal levels of prolactin, estrogen, and progesterone promote the development of breast tissue and stimulate milk production. After delivery, with the decrease of progesterone, prolactin levels rise within the mammary receptor cells to allow for lactation, or milk secretion through the nipples.
Prolactin levels do not remain elevated after delivery, however. Only while the baby is suckling on the breast do prolactin levels typically increase. During breaks from breastfeeding prolactin levels normally drop.
Prolactin During the Menstrual Cycle
Levels of prolactin also vary throughout the menstrual cycle, with higher levels observed during the ovulatory and luteal phases compared to the follicular phase.
It's important to note that the rise in prolactin during the ovulatory and luteal phases is relatively modest compared to the significant changes in other hormones like estrogen and progesterone during this time.
Essentially, the main role of prolactin during the menstrual cycle is not so much related to reproduction but rather the role of maintaining breast health and supporting lactation at the possibility of pregnancy.
During the follicular phase (days 1-13), prolactin levels are relatively low because the focus is on follicle-stimulating hormone (FSH) and luteinizing hormone (LH) to develop the ovarian follicles that will release eggs. Prolactin levels usually begin to rise slightly during the ovulatory phase (day 14) due, in part, to the rising levels of progesterone.
As the luteal phase (days 15-28) progresses, prolactin levels continue to rise under the influence of rising progesterone in preparation for a potential pregnancy. It is during this phase that women typically experience PMS symptoms like breast enlargement & tenderness or Cyclic Mastalgia, pelvic discomfort, irritability, headaches, premenstrual acne, and cravings.
Medical research has also noted that women with a shorter luteal phase during the menstrual cycle can experience abnormally high prolactin levels, making it more difficult to become pregnant.
Symptoms of High Prolactin Levels
In addition to experiencing difficulties conceiving, women with high levels of prolactin can also suffer from irregular menstruation and infertility. Loss of libido, pain during sex due to vaginal dryness, and a milky discharge from the nipples when not pregnant or breastfeeding are other common symptoms of high prolactin levels.
Additional Causes of High Prolactin Levels
As well as having a shorter luteal phase during the menstrual cycle, several other factors, medications, and conditions can cause higher-than-normal levels of prolactin in the female body.
A prolactinoma, which is a non-cancerous tumor on the pituitary gland, is the most common cause and is usually treated with medication or surgery. Irregular periods, kidney issues, an underactive thyroid, and shingles are also known to cause high prolactin levels.
Medication that affects the production of dopamine can cause prolactin levels to rise too, such as blood pressure medication, pain medication containing opioids, antipsychotic meds, and certain medicines for nausea & vomiting.
How to Treat High Prolactin Levels
Those experiencing symptoms of high prolactin are advised to schedule a check-up and blood tests with their doctor for diagnosis and treatment options.
If you have high prolactin due to a medication you are taking, your levels will typically return to normal within 3-4 days of completing the medication. However, should you suspect that any long-term medication you are required to take is affecting your prolactin levels, make an appointment with your healthcare provider about alternative medication and treatment options.
On the other hand, should you suffer from regular PMS symptoms like breast enlargement and tenderness, cravings, headaches, or mood swings, a regular intake of Vitex (Chasteberry) is highly recommended. Used as an herbal remedy for generations to treat symptoms of PMS, and menopause, and improve fertility, Vitex is widely known to reduce high levels of prolactin.
Benefits of Vitex (Chasteberry) for High Prolactin
More than 50% of participants in a medical study who took Vitex supplements for three menstrual cycles reported a significant decrease in breast tenderness associated with PMS.
Conclusions after another study showed that 93% of women who took Vitex supplements over three consecutive months reported a substantial improvement in PMS symptoms such as pelvic discomfort, irritability, premenstrual acne, and cravings.
Symptoms associated with both perimenopause and menopause like mood swings, interrupted sleep, low libido, and vaginal dryness have also been proven to improve with a regular intake of Vitex. Additionally, due to its effect on prolactin levels, vitex is also believed to improve female fertility.
Abnormally Low Prolactin Levels
Prolactin levels in females are typically low when they are not pregnant or breastfeeding, however, abnormally low levels of prolactin are extremely rare.
The main symptom of abnormally low prolactin levels is a lack of breast milk when breastfeeding which is commonly caused by a condition called Hypopituitarism. Stemming from damage to or excessive pressure on the pituitary gland, hypopituitarism inhibits the production and release of one or more hormones.
That said, many women who do not suffer from hypopituitarism are also known to experience a lack of breast milk. In these cases, Vitex (Chasteberry) is one of the most recognized natural remedies for improving lactation.
Results from a well-acknowledged German study showed that new mothers taking a controlled amount of Vitex daily produced substantially more amounts of milk compared to mothers who did not take Vitex. (It is, however, important to note that Vitex should not be taken during pregnancy. Only after delivery to aid in the production of breast milk)
If you experience symptoms of excess prolactin such as irregular periods, infertility, loss of libido, or vaginal dryness, schedule an appointment with your healthcare provider to have your levels checked with a blood test.
Verywell Health - Symptoms of High Prolactin Levels - https://www.verywellhealth.com/what-is-prolactin-2616429
You & Your Hormones – Prolactin - https://www.yourhormones.info/hormones/prolactin/
Endocrine Society – Hyperprolactinemia - https://www.endocrine.org/patient-engagement/endocrine-library/hyperprolactinemia
National Library of Medicine - Prolactin levels during the menstrual cycle - https://pubmed.ncbi.nlm.nih.gov/1009676/#:~:text=Non-systematic%20changes%20occurred%20in,than%20during%20the%20follicular%20phase
Thieme Planta Medica - Vitex agnus-astus Extracts for Female Reproductive Disorders - https://www.thieme-connect.de/products/ejournals/abstract/10.1055/s-0032-1327831
National Library of Medicine - Treatment of cyclical mastalgia with a solution containing Vitex agnus extract: results of a placebo-controlled double-blind study. The Breast 1999;8:175-81. - https://pubmed.ncbi.nlm.nih.gov/14731436/