Validated for most ethnicities (Cut-off ≥8). Smaller thresholds may apply to certain populations (e.g. East Asian).
Guidelines & Evidence
Clinical Details
Section 1
When to Use
Primary Clinical Uses
Standardized visual assessment to quantify the severity of hirsutism in women
Fulfilling the clinical hyperandrogenism criteria for the diagnosis of Polycystic Ovary Syndrome (PCOS)
Monitoring therapeutic response to anti-androgen treatments or oral contraceptives
Patient Context
Hirsutism (excess terminal hair in a male-pattern distribution) is distinct from hypertrichosis (generalized excess hair everywhere). The FG score exclusively targets androgen-sensitive regions to differentiate the two.
Section 2
Formula & Logic
Scoring Logic
Evaluates terminal (dark, coarse) hair growth across 9 androgen-sensitive body areas. Each area is assigned a score from 0 (no terminal hair) to 4 (extensive visible hair). Maximum score is 36.
The 9 Assessment Areas
Upper Lip
0-4 points
Chin
0-4 points
Chest
0-4 points
Upper Back
0-4 points
Lower Back
0-4 points
Upper Abdomen
0-4 points
Lower Abdomen
0-4 points
Upper Arms
0-4 points
Thighs
0-4 points
Section 3
Pearls/Pitfalls
Key Nuances
Highly subjective tool with notable inter-observer variability.
Recent hair removal (shaving, plucking, waxing, laser) drastically masks the true baseline score. Patients should ideally not perform hair removal for 4 weeks prior to assessment.
Racial and ethnic variations are critical: The normal density of body hair varies wildly by genotype. Standard cutoffs may drastically overdiagnose or underdiagnose hirsutism depending on the patient's heritage.
Modifications
The original 1961 score included 11 body parts. The "Modified" Ferriman-Gallwey score (mFG), universally used today, removed the lower leg and forearm areas, as hair in those regions is typically independent of androgen levels.
Section 4
Next Steps
Interpretation and Action
01
Calculate total mFG Score.
02
Determine clinical hirsutism based on general cutoff (commonly ≥8, though ≥4-6 may be used in certain ethnic populations like East Asian women).
03
If positive and accompanying oligo/anovulation or PCO morphology: Meets Rotterdam criteria for PCOS.
04
Order biochemical evaluation: Total and Free Testosterone, DHEAS, 17-OH Progesterone (to rule out CAH).
05
If virilization is rapid or severe: Immediately screen for androgen-secreting ovarian or adrenal neoplasms.
Section 5
Evidence Appraisal
Landmark References
Clinical assessment of body hair growth in women.
Ferriman D et al. • J Clin Endocrinol Metab.. 1961;Original publication introducing the scoring method.
Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline.
Martin KA et al. • J Clin Endocrinol Metab.. 2018;Validates the mFG score as the gold standard for clinical diagnosis of hirsutism and emphasizes population-specific thresholds.
Section 6
Literature
Creators
Developed by Dr. David Ferriman and Dr. J.D. Gallwey in 1961. The current modified version (which dropped 2 regions to establish the 9-region standard) was later refined by Hatch et al. in 1981.
