Snippet from the article:
Androgenetic alopecia affects both men and women. In men it produces male pattern hair loss with bitemporal recession and vertex baldness. In women it produces female pattern hair loss (FPHL) with diffuse alopecia over the mid-frontal scalp. FPHL occurs as a result of nonuniform hair follicle miniaturization within follicular units. Diffuse alopecia is produced by a reduction in the number of terminal fibres per follicular unit. Baldness occurs only when all hairs within the follicular units are miniaturized and is a relatively late event in women.
The concepts of follicular units and primary and secondary hair follicles within follicular units are well established in comparative mammalian studies, particularly in sheep. However, discovery of these structures in the human scalp hair and investigation of the changes in follicular unit anatomy during the development of androgenetic alopecia have provided a clearer understanding of the early stages of androgenetic alopecia and how the male and female patterns of hair loss are related.
Read the full abstract — Hair loss in women: medical and cosmetic approaches to increase scalp hair fullness
This is an interesting article published in the British Journal of Dermatology (December 2011) which covers the subject of hair loss in women. The recommendations in treatment suggest early medical intervention with drugs like spironolactone, minoxidil, and finasteride. When the hair loss becomes advanced, hair transplants work well if the hair in the occipital area (donor area) remains relatively unaffected by the process found in the balding area. The article also suggests women should use camouflaging agents to help give the appearance of thicker hair. There’s nothing particularly groundbreaking in here, but it’s a good overview.
Based on our experience at NHI though, unfortunately the donor area is often not spared in the woman with advanced balding so that the number of good candidates are limited. We have found that if the donor area has significant miniaturization, transplanting this hair to the thinning area often fails to give full benefits. Many women aren’t surgical candidates for this reason.
Read the rest — 
