Drug transfer during intimate moments: A key issue in doping control that can be documented by hair tests of the athlete and the partner.

The presence of a prohibited substance or its metabolites or its markers in an athlete's sample constitutes the more frequent anti-doping rules violation. In the world anti-doping code, it is indicated (point 10.5) that if someone establishes in an individual case that the athlete bears no fault or negligence, then the otherwise applicable period of ineligibility shall be eliminated. The conditions that have to be met to fix the no fault or negligence evidence are described in several other points of the code. The following two points are of paramount importance: 1. the athlete or his/her legal representative must present verified circumstances of contamination and the source of contamination must be identified; and 
2. there must be verified claims by the athlete about the fact that he/she did not knowingly take the prohibited substance, i.e., that the violation was not intentional.In recent years, several cases of contamination involving drug transfer during intimate moments have been reported. This later situation was first reported in 2009 with the Richard Gasquet case. Since that time, several athletes have been allowed to return to competition with no charge based on strong evidence that the source of contamination was drug transfer during intimate moments. As some of these cases are public and because the author performed hair tests for the majority of the international athletes involved in such procedures, the strategy of the defence and the scientific bases of discussion are reviewed in this article.