Erythrocyte sedimentation rate (ESR) is a blood test that measures how quickly red blood cells settle at the bottom of a test tube in one hour. It is a non-specific marker of inflammation in the body. A higher ESR indicates that there is more inflammation present. Observed variations in ESR exist between the sexes, with women typically exhibiting higher values than men. Several physiological factors contribute to this difference.
Understanding the reasons for this difference is crucial for accurate interpretation of ESR results in clinical settings. Elevated ESR, without considering sex-specific norms, can lead to misdiagnosis or unnecessary further investigations in women. Hormonal influences, particularly estrogen, are known to affect levels of certain proteins in the blood (such as fibrinogen) that influence erythrocyte aggregation and, consequently, sedimentation rate. Furthermore, physiological changes associated with menstruation and pregnancy can transiently elevate ESR.
