Estrogen hormone therapy stabilizes lateral hairline in transfeminine patients: Implications for facial feminization surgery.

HRT duration was a significant negative predictor of lateral forehead length in TGNB AMAB patients.

• Lateral forehead length decreased by 0.07 cm with each year of feminizing hormone therapy (B=-0.07, 95% CI [-0.10 to -0.04], p < 0.001)
• This finding indicates that longer duration of estrogen therapy is associated with a shorter (less receded) lateral forehead measurement
• The study included 171 patients with a median HRT duration of 2.0 years (IQR 1.0-6.0 years)
• All patients were aged 30 years or older and assigned male at birth

Age was a significant positive predictor of lateral forehead length, indicating greater lateral hairline recession with older age.

• Age positively predicted lateral forehead length (B=0.06, 95% CI [0.03-0.08], p < 0.001)
• A greater lateral forehead length indicates more hairline recession
• The median age of the study population was 36.0 years (IQR 32.0-46.0)
• All patients were aged 30 years or older at time of initial consultation for facial feminization surgery

Use of hair treatments (finasteride, dutasteride, or minoxidil) was a significant positive predictor of lateral forehead length.

• Presence of hair treatments positively predicted lateral forehead length (B=0.66, 95% CI [0.14-1.18], p = 0.01)
• Hair treatments included finasteride, dutasteride, or minoxidil
• A positive coefficient suggests patients using these treatments had greater lateral forehead length (more recession) at consultation
• This may reflect that patients with more hair loss were more likely to seek additional hair treatments

No significant predictors were identified for central forehead length in the multivariable linear regression model.

• Multivariable linear regressions revealed no significant predictors for central forehead length
• Variables tested included age, HRT duration, presence of spironolactone, and presence of other hair treatments
• Global health scores were incorporated as a proxy for psychological effects on hair loss
• The finding suggests estrogen therapy's stabilizing effect on hairline is specific to the lateral rather than central hairline

The study population consisted of 171 TGNB AMAB patients aged 30 or older seeking facial feminization surgery.

• Total sample size was 171 patients
• Median age was 36.0 years (IQR 32.0-46.0)
• Median HRT duration was 2.0 years (IQR 1.0-6.0)
• Central and lateral forehead lengths were measured at initial consultation visits
• Chart review collected variables including age, HRT duration, presence of spironolactone, and use of finasteride, dutasteride, or minoxidil