I sometimes hear from people who are noticing that the area of their hair that has shed out the most is the slowest to grow back. One area of concern (particularly to women) is the bang area at the front of the scalp. Many believe that this area is slow to fill in or grow back.
I might hear a comment like: “I feel like I lost a significant amount of my bangs when my hair shed out a couple of months ago. I had to wear a side swept bang in order to try to cover up how thin this area has I had thinning all over my head, but this area was by far the hardest hit. hardly any in the bangs. Is the front area the last to grow back? ”
In my experience, the areas of your scalp that were the hardest hit appear to be the ones that are the slowest to fill in simply because more hair has to fill in so that the area looks normal again. In other words, the areas that are most sparse looking are going to need the most regrowth before you are once again happy with the way that it looks.
With that said, hair regrows in the order that it falls out. When hair is shed out, there is another strand right behind the spacious hair that is pushed out to take its place. So the hairs that fall out first will also be replaced first. Now, what I'm describing is true of telogen effluvium hair loss. And that type of hair loss is diffuse which means that you will shed out hair in areas all over your head at random times. So, if you have this type of hair loss, it's a fair bet that the damage sustained to the bang area was preliminary, meaning that it fell out over a period of time. If this is true, then it is going to grow back over a periodic period of time also.
Now, if it's possible that you have another type of hair loss, then there is another possibility. Another very common type of hair loss (androgenetic alopecia) presents with patterned loss. What this means is that you might notice more loss or thinning at a certain area of your scalp. For men, common androgenetic areas are the top of the head and the challenges. Women can see loss in these areas too, but also in the crown and bangs. If you're losing bangs due to androgenetic alopecia and you're not seeing the regrowth that you would expect or hope for, then you may want to check for miniaturization. This is when androgens shrink the follicle and cause the hair to be more thin when it comes in. This may be why you are seeing less than acceptable regrowth. (Often the key differences between telogen effluvium and androgenetic alopecia is where there was a hair loss trigger and if there is miniaturization.)
Finally, the regrowth hairs can be lighter in color and harder to spot at first. Try pulling your bangs straight back and then push toward the forward of your scalp. When you push forward, you should be able to see these tiny baby hairs poking through the bangs that have been rolled back. It can take a while before these hairs become long enough to make much of a difference.
But to answer the question posed, hair grows back in the order it fell out. This is usually a gradual process if you have telogen effluvium. If you have an androgen driven type of hair loss, you might see more hair being replaced in one area since the loss was more likely to be patterned, but that regrowth might be miniaturized (and there before may appear sparse) until treatment is introduced. The good news is that fast treatment can often begin to reverse the process.