True prolactin, a pituitary hormone, is vital in post-partum lactation, maintaining breast milk production, growth and development of mammary glands, suppressing ovulation during breastfeeding, and maintaining reproductive and endocrine regulation. Prolactin estimates protein-bound form and bioactive true prolactin in blood. It helps healthcare providers evaluate endocrine and reproductive disorders, infertility, irregular menstrual cycles, and lactation disorders and guide appropriate treatment.