Normal eGFR for a 48-Year-Old Female
For a healthy 48-year-old female with no medical conditions, the normal estimated glomerular filtration rate (eGFR) is approximately 90-100 mL/min/1.73 m², with physiological decline beginning after age 40 years. 1, 2
Age- and Sex-Specific Normal Values
Young adult women (age 20-40) have a normal eGFR range of approximately 90-120 mL/min/1.73 m², with median values around 101 mL/min/1.73 m² at age 20. 1, 3
At age 48, a healthy woman would be expected to have an eGFR in the range of 85-95 mL/min/1.73 m², accounting for the physiological decline that begins after age 40. 1, 2
The mean GFR remains approximately 107 mL/min/1.73 m² until age 40, then begins to decline at a rate of approximately 0.75 mL/min/year in both men and women. 4, 2
By age 79, median eGFR in healthy women decreases to approximately 63-64 mL/min/1.73 m², demonstrating the progressive age-related decline. 3
Clinical Interpretation Thresholds
eGFR ≥90 mL/min/1.73 m² is considered optimal kidney function and represents normal renal function for younger adults. 1
eGFR 60-89 mL/min/1.73 m² represents mildly decreased kidney function but may be normal for older adults, particularly those over age 60. 1
eGFR <60 mL/min/1.73 m² represents loss of half or more of normal adult kidney function and is the threshold for defining chronic kidney disease when persistent for ≥3 months. 1, 5
For a 48-year-old woman, an eGFR in the 85-95 mL/min/1.73 m² range would be considered normal, while values persistently below 60 mL/min/1.73 m² would warrant further evaluation. 1, 2
Important Clinical Caveats
Serum creatinine alone should never be used to assess kidney function—always calculate eGFR using validated equations such as CKD-EPI. 4, 1
A single eGFR measurement should not be used to diagnose chronic kidney disease; abnormalities must persist for ≥3 months. 1
Extremes of muscle mass, obesity, or recent acute illness can affect eGFR accuracy and may require measured GFR using exogenous filtration markers. 4, 1
eGFR >60 mL/min/1.73 m² does not exclude kidney disease if other markers are present, such as albuminuria ≥30 mg/g creatinine or structural abnormalities on imaging. 1
The CKD-EPI equation (refit without race variable) is the preferred method for GFR estimation and provides superior accuracy compared to older formulas, particularly at GFR values >60 mL/min/1.73 m². 4