American Claressa Shields is underneath investigation after testing constructive for marijuana following her win over heavyweight Danielle Perkins on 3 February in Michigan.
The 29-year-old – who’s a three-weight undisputed champion – has been suspended from combating within the state by the Michigan Unarmed Fight Fee.
Shields examined constructive after offering an “oral fluid pattern” after the struggle.
Marijuana is banned in-competition by the World Anti-Doping Company (Wada).
American sprinter Sha’Carri Richardson missed the Tokyo Olympics in 2021 after receiving a one-month ban following a constructive medication check for marijuana.
The WBO, which is a sanctioning physique and doesn’t have the ability to droop boxers, has requested a “present discover” from Shields, asking her to clarify herself, whereas the Michigan Fee has opened its personal investigation into whether or not she ought to face disciplinary motion.
“Ms Shields’ conduct as a licensed skilled boxer constitutes an imminent risk to the integrity {of professional} boxing, the general public curiosity, and the welfare and security {of professional} athletes,” the Michigan Fee mentioned.
Final week, Shields addressed rumours of a failed medication check on social media, saying she was a “clear athlete”.
BBC Sport has contacted Shields for remark.
Underneath the WBC’s clear boxing programme, Shields and Perkins would have been topic to drug testing by the Voluntary Anti-Doping Company (Vada).
Shields received gold on the Olympics aged 17 and has received titles in a number of weights as knowledgeable boxer.
She is undefeated in 16 fights and was the primary boxer, male or feminine, to win undisputed titles in three completely different weights within the four-belt period.
