What is the normal value for prolactin?

Prolactin is a polypeptide hormone—also known as lactogenic hormone—that is secreted by the anterior pituitary gland. What, then, constitutes the normal prolactin level?

What Is the Normal Prolactin Level?

Normal prolactin levels vary with age. In women aged 20–25 years, the typical range is 0.5–0.68 mmol/L. During youth, endocrine system function is relatively robust, resulting in higher baseline prolactin levels. For women aged 25–30 years, prolactin levels generally fall within 0.41–0.45 mmol/L; mild age-related decline in endocrine function leads to comparatively lower values. In women over 30 years of age, prolactin levels typically range from 0.23–0.25 mmol/L, correlating with decreased metabolic activity.

Prolactin secretion increases markedly during late pregnancy and lactation in women to support mammary gland development and milk production. In healthy adult men, serum prolactin levels are typically <20 μg/L; in non-pregnant women, levels are also low—generally <40 μg/L. Elevated prolactin levels constitute a condition termed hyperprolactinemia, a disorder reflecting dysfunction of the hypothalamic–pituitary–gonadal axis. Key clinical manifestations include significantly reduced menstrual flow, amenorrhea, infertility, and menopausal-like symptoms.

When serum prolactin concentration exceeds the normal range, the condition is diagnosed as hyperprolactinemia. We hope this information has been helpful. Wishing you good health and happiness!