On the ethical side of things, we realize that an infant cannot give informed and competent consent to the modification of their body. If ten years down the road, your child doesn't want to have pierced ears, the fistulas may be too sable to close up. It's also a moderately painful procedure, and infants have no way of mentally coping with that.
On the physical side, a piercing is a mildly invasive procedure that does produce some pain. An infant doesn't understand that the majority of the pain is temporary, or that there will be residual pain in the coming weeks. You can't explain to an infant that they shouldn't touch or pull on the jewelry, nor do they understand the need to clean the wounds.
As a whole, we at Master Pierce generally suggest that you wait until your child is old enough to ASK for the piercing. If your child has asked and has shown the ability to understand basic hygiene needs for a fresh wound, we encourage you to call us to schedule a consultation at (561)753-1770.