What causes patches of hair loss within the beard line of males? How do you stop further hair loss?

i;m not sure you can stop it. but I do think it is hereditary.my husbands hair is doing the same thing so he just cut it all off.What causes patches of hair loss within the beard line of males? How do you stop further hair loss?
i think it might be a chemical inbalance or stress:)What causes patches of hair loss within the beard line of males? How do you stop further hair loss?
im shur its a hetertary whic mean your dad eather had the same problem or a great grand father and its past down to u
i don't know i am not a male