How do you tell who will get male pattern baldness?

ALOPECIA TX. Alopecia or hair loss may be multifaceted . You need full Exam &lab work up especially Vit d/Thyroid studies /TESTOSTERONE/ b12 and folate. If they are normal start high dose Biotin zinc B12 and folic acid.. Rogaine (minoxidil) and Propecia may be helpful. If there is no improvement consult dermatology for biopsy to rule out auto-immune ALOPECIA AERATA.. With supplements start low and go slow.
Chest hair. There's a pretty good correlation with the overall pattern of masculine body hair and how soon a man will develop male pattern baldness. The teen who is the envy of his peers because of his super-hairy chest is likely to have visible loss on the top of his head by his late 20's. It's not hard-and-fast, but works pretty well. Many women find a hairy/balding man extra sexy. Good luck.