Bulgarian teenager Sesil Karatantcheva has been banned for two years for doping, the International Tennis Federation said on Wednesday.

An independent anti-doping tribunal ruled that samples provided by the 16-year-old at the French Open last May and out of competition in Tokyo in July had tested positive for the banned steroid nandrolone, the ITF said in a media release.

The three-man tribunal heard the case over two days in London [Images] last month and rejected Karatantcheva's defence.

French daily sports paper L'Equipe said at the time she had explained the high level of nandrolone by saying she was pregnant. She said she then had a miscarriage.

A pregnancy test carried out by a French lab on the player's urine sample was negative, the paper said.

The Bulgarian, now ranked 41 in the world, reached the quarter-finals at last year's French Open when she was aged 15, beating Venus Williams [Images] on the way.

She must now forfeit prize money of 110,000 euros ($133,000) from Roland Garros and another $128,000 from later competitions. The ban rules the teenager out until January 1, 2008, the ITF said.

Bulgarian Olympic Committee chairwoman Stefka Kostadinova said: "It's really very unpleasant. She is an exceptional talent and in my opinion two years is a very harsh punishment."

Karatantcheva's ban is the heaviest handed out to a female professional tennis player and she is only the second women's player to be banned for drugs, the ITF said.

Spaniard Lourdes Dominguez Lino was suspended for three months after testing positive for cocaine in 2002.

Karatantcheva has three weeks to decide whether to appeal.

Last month Argentina's Mariano Puerta was banned for a record eight years after testing positive for the banned stimulant etilefrine following his 2005 French Open men's final defeat by Spain's Rafael Nadal [Images].

(Additional reporting by Angel Krasimirov in Sofia)

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