The International Tennis Federation (ITF) has confirmed that American tennis player Varvara Lepchenko tested positive for banned substance meldonium on four occasions but will not face a suspension as she "bore no fault or negligence" for the anti-doping violation.

Samples provided by the Uzbekistan-born 30-year-old during the Brisbane International in January showed traces of meldonium, which was added to the World Anti-Doping Agency list of prohibited substances on January 1 this year.

Meldonium was also found in out-of-competitions samples supplied by the world number 79 in February, March and April.

The ITF revealed that Lepchenko was provisionally suspended on March 12, but successfully appealed against that decision a month later "on the grounds that the meldonium present in her samples came from a course of mildronate tablets that she stopped taking on or around 20 December 2015" and was back in competitive action in Rome in May.

WADA advised the ITF that the concentrations found in Lepchenko's samples would support her account that she has not used meldonium since was added to the list of banned substances, so will not face another suspension.

Lepchenko loses the points and prize money she was awarded for reaching the quarter-finals in Brisbane.

Maria Sharapova was banned for two years in June after the former world number one also tested positive for meldonium during the Australian Open.