"Photo by PR Photos"
What impresses me the most, however, is the quality and density of her hair for a woman in her 60s. After menopause, it's common for female pattern hair loss and more minor 'thinning' to kick in in most women. Loss of hair volume on the crown, recession in the temporal points, all of these are common in post-menopausal women.
That's why Mrs. Clinton's hairline is quite remarkable. Although I've never treated her, I suspect she might be taking dietary supplements to boost the health of her follicles. Or she could just have really good genes.
I'd advise the majority of women over age 40 to take dietary supplements that add to their follicle health. One scientifically tested product that I recommend to clients is Viviscal. Other options for women with thinning hair: Rogaine For Women, Latisse, Low Level Laser Therapy, and off-label options like finasteride, dutasteride, etc. However, it's important to always consult with a qualified hair restoration specialist first - make sure he or she is board-certified with the American Board of Hair Restoration Surgery.