The Hanafi jurists have stated that it is permissible to pierce the females ears to put earrings and the like for beautification. They also stipulated that it is permissible to wear rings in the nose, as it is a common adornment for women. None of these is permissible for male children because Sharia permits the wearing of cosmetics and adornment for women, not men. It is not permissible to accustom children to anything other than what they are prepared for at old age. The male children should be accustomed to manhood responsibility while the female children should be accustomed to women’s morals. Anything against that is prohibited.
As for tattooing, it is prohibited even for women because the Prophet (peace be upon him) forbade it and cursed the woman who tattoos and the woman who asks for it. The pretext for this prohibition is not in the pain that one would feel, and so it should not be compared to that of piercing the ears.
Also, changing the natural appearance as it appears with tattooing does not have equivalent analogy with piercing ears or pricking. The hole in piercing merely creates a place for the piece of jewelry to hang on which is allowed.