Wales has banned under-18s from having intimate piercings to protect their "health and well-being".
The government says a study in England shows about one-third of all people between the age of 16 and 24 who had body piercings experienced complications
The law makes it illegal for piercing practitioners to organise or carry out the piercings on anybody under the age of 18.
It is illegal for anyone to give under 18’s an intimate body piercing even with parental permission #walespiercinglaw https://t.co/mI9IpPF6sw pic.twitter.com/LurSuJ2wxP
— DHSSWales (@DHSSwales) February 1, 2018
Piercing is banned on 10 specific intimate body areas - including genital areas, buttocks, nipples and tongues.
Wales is the first country in the UK to introduce the nationwide ban.
In Ireland, there is no legal minimum age to get a piercing or regulation of such businesses.
The chief medical officer for Wales, Dr Frank Atherton, said: "We recognise that people are free to choose what they want to do, we're not the public health fun police here in Wales.
"But we believe that people at the age of 18 can make those choices, people under that age we think should be supported through child protection".