Observational Study of Asymmetric Hair Loss in Men



To quantify the observation that ‘hairlines and hair losses in male pattern baldness are asymmetric., and the implications which therefore arise regarding its diagnosis and treatment.


This study involved 100 new male clients (Norwood classification 2-5).
Each had requested hair restoration and there had been no previous medication or surgery.
Only frontal loss symmetry was assessed.
Patients with Ludwig hair loss pattern were excluded.
Assessment included the frontal hairline and recession of the temporal fringe.
Each patient was assessed to establish levels of hair loss on the left and right sides.
In very few cases did it appear to be almost equal but a decision was made to adhere strictly to only two endpoints, left or right.
As the assessor I counted the results at the end of the study. This took six months to complete.


77 (77 %) of the men studied demonstrated greater losses on the right side
23 (23%) demonstrated greater losses on the left side.


This study confirms the general observation by both surgeon and patients that “hair loss in the male is usually asymmetric with greater levels of loss being exhibited on the right side. (Ratio right to left: 3:1).


Hair loss is asymmetric. Realising this is important because as hair restoration specialists: we need to understand the normal patterns of hair loss as well as the pathology.

We endeavour to reconstruct natural hairlines appropriate to individuals. Given that no human body is symmetrical – not faces hands or limbs, we must accept that a symmetrical hairline will probably look unnatural.
Patients tend to request that surgeons “even up” their hairline, but too much “perfection” should be avoided.

Secondly, surgeons draw hairlines horizontally, meeting the temporal fringe at a fairly sharp angle. This looks more natural and should remain so even when there has been further hair loss in say five years time. This is generally accepted as the most ethical treatment for patients’ long-term benefit.

However, on the side where hair loss is greater, the temporal region can still appear to have a large recession pattern. This is particularly true if there has been a greater recession of the temporal fringe. The patient then requests the surgeon to angle the hairline downwards to “fill in” the recession. It looks OK in the mirror but we can see from the side that the natural angle is lost – the Simian appearance.

When diagnosing hair loss, it is useful to keep in mind the natural extremes. I have two patients showing such variation.

Patient 1 possessed an asymmetric hairline even before puberty. The left temporal region was very high and recessed. The right side was at the normal level for a man in his early twenties without hair loss. He didn’t have a strong family history of MPB and simply appeared to have an extremely asymmetric hairline. Dr Shiell has made us all aware of Triangular Alopecia but I don’t think my patient had this.

Patient 2 had developed greater asymmetric loss after puberty. The left side had receded further and faster than the right. I found no other cause for this and diagnosed MPB (an extreme variation).

Both patients received hair transplantation to even up their loss and both were counselled about further loss. However, even though their hairlines appeared similar, the cause was not the same.

These two patients represent an anomaly in this study. I had assumed :
i) That their hairlines were “fairly” symmetrical until puberty and the onset of classic male pattern hair loss.
ii) the subsequent hair loss was not symmetrical. Whereas this is not true in Patient 1 as it was for the one hundred patients studied.
iii) that any apparent recession from Norwood 1 was purely due to hair loss. However, some patients state that their hairlines have always been “high,” implying that their basic hairline pattern was always a V shaped or receding pattern and that MPB has simply accentuated this.

If we accept ‘that hair loss is usually asymmetrical’ we can maximise the use of grafts. Instead of trying to create an equal hairline we can deliberately favour placing a lower or more densely packed hairline on one side only, allowing the other side to “fade out.” Clearly this is an aesthetic skill, which shouldn’t be taken to extremes, but patients will often ask surgeons to favour their parting side more than the other. This seems reasonable.

Conflicts of Interest


© Richard Rogers MB ChB, MRCGP, FTTS (Fellow and founder member of The Trichological Society).