Establishment of reference interval of serum prolactin in an Indian population

Reference data on serum prolactin levels based on a representative Indian sample are still lacking. The western normative laboratory values used for clinical diagnosis may not be applicable to Indian population. The objective of the study was to measure the serum prolactin levels in healthy Indian male and female in order to establish reference interval and to compare with the available reference intervals. It is a cross- sectional study done in West Bengal, India.

Based on the history, clinical examination and laboratory investigations, serum prolactin levels of 1316 apparently healthy subjects were estimated by microplate immunoenzymometric assay using pooled serum. Statistical analysis was performed using SPSS software.

The serum prolactin levels for all ages were 10.7 ± 3 ng/ml in healthy male and 11.6 ± 2.8 ng/ml in healthy female. Decade-wise analysis of serum prolactin level in female showed a steady increase from 20-29 years to advancing decades until 4(th) decade and thereafter declines steadily although it was not same for male.

Our study will help each laboratory to formulate their own reference interval for prolactin. As of now they were dependent either on the values written on the kit-literature supplied by the reagent manufacturing company or the reference intervals of foreign population.