Microdermal rejection rates are suggested to be around 2 per cent, in my opinion the rejection rates are slightly higher around 5 percent.
In my experience the following factors seem to contribute to rejection
Try to choose a low impact site for insertion
At the time of insertion you should discuss with the piercer the placement ie placing a dermal on the hip or neckline where clothing catches all the time can cause repeated trauma that can lead to the anchor being dislodged to the point it is rejected.
If you are getting your dermal to lace or slave wait 3 months before putting that sort of pressure on the piercing
dermal anchors need to be placed correctly, by inserting them first at a 90 degree then stretching then level. If the small foot is not inserted level with the longer foot, the dermal will sit at an angle causing the foot to be pushed out.
If for any reason the smaller foot is dislodged it is in my experience better to remove the anchor, let things heal and start again.
An extension is often a good idea if there is bleeding or swelling around the dermal.
An experienced dermal piercer is essential
the leading cause of rejection
its so important not to get them knocked, tugged, caught or pulled
In my experience once you unseat one side to the foot the anchor just pushes out, taping or reinserting doesn't seem to work. Best answer here is to start again
Care should be taken that there are no underlying metal intolerance problems, this can lead to what is thought to be an infection and the anchor grows out.
Sometimes dead skin cells to build up between the skin surface and the underside of the dermal top. This creates upward pressure on the dermal top and can cause rejection. This happens reasonably often to people with dry skin or psoriasis type skin conditions.
It is important to make sure your dermal is cleaned well.
A previous rejection of body jewellery in the same area does increase the risk of further rejection
Piercings reflect your health, if you are tired, rundown and have infections or health problems your piercings will be slow to heal or not heal.
Multivitamins, good diet and looking after yourself is really important
Good personal hygiene is essential, using protex soap will keep the skin bacteria down
Remember to wash your hands before touching your piercing