A: Hair loss is due to the action of DHT (a byproduct of testosterone) on hair follicles that cause them to shrink and eventually disappear (the process is called miniaturization). The follicles on the back and sides of the scalp are not sensitive to DHT and therefore don’t bald (miniaturize).

When you transplant hair from the back and sides to the bald area on the front or top of the scalp the hair follicles maintain their original characteristics (their resistance to DHT) and therefore they will continue to grow.

A: Generally in a second procedure, a patient can expect less swelling post-up although the reason for this is not known.

There will also generally be less shedding in the second hair transplant session since the weak miniaturized hair that will be shed is often lost in the first session and the previously transplanted hair is generally more resistant to shedding.

In a second session we generally, but not always, transplant fewer numbers of grafts.

If the old scar in incorporated into the new incision, then there will be slightly less hairs per graft since the density in and around the scar will be slightly altered.

For those who are bald, the second hair restoration is sometimes less dramatic than the first since the second is used for fine tuning rather than taking the person from completely bald to having hair.

A: You are describing accurately how hair grows after a hair transplant.

After the hair restoration procedure, the transplanted stubble is shed and the hair goes into a dormant phase.

Several months later, growth begins as fine, vellus hair that thickens over time. The hair usually does not have its original thickness right away.

Typically, growth occurs in waves so that initially some areas will have more hair than others. Over the course of a year the cycles will even out and the hair will thicken to its final diameter.

A: In general, only miniaturized hair (the hair that is affected by androgens and that has begun to decrease in diameter) is shed after a transplant. This hair would be lost in the near term anyway.

Existing healthy hair is unlikely to shed, but if it were shed, you could expect it to grow back.

A: The follicles are firmly fixed in the scalp 10 days following the hair transplant. Hair is shed from the follicle beginning the second week after the procedure. This is perfectly normal and does not represent any loss of grafts.

What you are seeing is the root sheath that is shed along with the hair shaft. This looks like a little bulb, but is not the growth part of the follicle and should not be a cause for concern.

Two weeks following the hair transplant you may shower and shampoo your scalp as you normally did before the procedure without any risk of losing grafts.