Dangers of doing second hair transplant session within 3 months of the first one?

It can take 6 to 12 months after surgery to see results.  You should not be considering surgery until you see the results from your surgery.  There may be exceptions to this but that is done on a case to case basis with a doctor (in person) after an examination.

Hello in Connecticut,You've asked a really good question:  It is generally a really bad idea to go back for a second procedure only 3 months after the first, for several reasons:1.  You can expect most of the grafted hairs to be shed and disappear early on within a few weeks of the procedure.  This is normal. The hair then starts to grow again only after 3 months later, and complete hair growth is usually seen at 1 year.  So at this stage you really have no way of knowing how your scalp will look in 9 months, if you really do need more hair, and where best to put it.  In the meantime, you can help your hair fill in by using Minoxidil and Finasteride.2.  Going back in at 3 months could potentially damage grafted hair follicle that are in the telogen phase of the hair growth cycle and may not be visible to the surgeon.  You could lose good hair that way, and you can also lose hair around the transplant because of telogen effluvium (post-op shock loss).3.  The best way to tell where the hair grafts were placed and where they were not is for the surgeon to have taken a photo of your scalp right after the procedure or a day or two later.  Then you have an accurate map to base your plans - ask your surgeon if he/she took photos right after the procedure and look at them.4.  Most important:  It is not possible to restore normal looking hair density to the entire scalp in someone with Norwood class VII hair loss.  There just isn't enough donor hair available in the hair bank (the back and sides of the scalp) to cover the entire area of hair loss.  Part of the art of hair transplantation surgery lies in the surgeon's ability to design a graft pattern that concentrates on the critical areas of the front hairline, the temporal recession, and the area immediately behind the front hairline. Putting most of the hair grafts in these zones and in the correct pattern, direction and density will give the best results in terms of framing the face, and restoring a younger, healthier look.   If you have enough donor hair follicles, you can fill in more grafts either in the same session, or later once you know the final look, which is usually about a year.

In general, I advise patients to wait 10 months after first hair transplant before proceeding to the next one. A true Norwood Class 7 is usually not a good candidate for hair restoration. Wait till you see results and proceed appropriately.

I tell most people to wait until the grafts have grown in (about 8 months) then you can see what you need and maybe even reinforce the existing transplants if needed