Warsaw: A law on obligatory chemical castration for paedophiles convicted of rape and perpetrators of incest passed in parliament last September came into effect Tuesday in Poland.

Under the law, anyone convicted of rape of a minor aged under 15, or a close family member, "can be obliged by a court ruling to undergo pharmaceutical and psychological therapy in order to reduce sex drive," after having served a prison term.

Before making a ruling on the appropriate therapy, a court must consider the opinions of psychiatrists, sexologists and psychologist.

Under the law, prison terms for rape of a minor or incest have also been increased to three to 15 years from the current two to 12 years.

The new law introduces prison terms of up to three years for anyone convicted of attempting to seduce a minor under 15 over the Internet.

Prime Minister Donald Tusk first raised the controversial issue of chemical castration for convicted paedophiles and perpetrators of incest in September 2008 after a 45-year-old man was charged with having raped and held his 21-year-old daughter captive for six years.

The woman gave birth to two children, in 2005 and 2007, allegedly the result of having been raped by her father.