Authors

Mojgan Sanjari MD1 , Zohreh Safi B.S 2,Khatereh Mohammadi Tahroodi MD3

Affiliations

Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran

1 Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology
Sciences, Kerman University of Medical Sciences, Kerman, Iran;

2Pysiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran;

3Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran

Abstract

Objective: To compare the serum prolactin level in hyperthyroid and normal control females.
Hyperthyroidism is a common disease. Although a direct association has been demonstrated between
hypothyroidism and increased prolactin level, but this association has not been established for
hyperthyroidism.
Methods: Cross-sectional study in cases and control groups. Control group were chosen from those
participated in Kerman Coronary Artery Disease Risk Factors study (KERCADRS study). To select the
case group, all the women who referred to the laboratories of Kerman with TSH ≤0.5 mIU/L and met the
inclusion criteria entered the study.
Twenty hundred and thirty one women aged 15 to 50. Case group: 71 hyperthyroid women, control
group: 160 women with normal thyroid function matched in terms of age.
Results: The serum level of prolactin was 16.56±0.97 ng/ml (95 % CI: 15.41-15.71) in the control and
23.07 ±1.49 ng/ml (95% CI: 22.7-23.4) in the case subjects. Hyperprolactinemia was more common in
hyperthyroid group (16.5±0.97 vs 23.07±1.49 p<0.001). The prolactin level decreased with age.
Hyperthyroidism and estradiol increased the prolactin level. After adjusting for age and Estradiol,
hyperthyroidism increased the serum prolactin level (p<0.001).
Conclusions: The results of this study revealed that hyperprolactinemia is more frequent in hyperthyroid
females. Serum prolactin level can be increased in hyperthyroidism.