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It was ruled by the Court of Arbitration for Sport last month that the IAAF should make rules for XY chromosome athletes in sexual development competing in events ranging from 400m to a mile.
The South African double Olympic champion launched an appeal to the Swiss Federal Tribunal.
The CAS verdict was highly controversial.
Many high-profile current and former athletes have lined up on both sides of the debate.
"The Federal Supreme Court of Switzerland has ordered the IAAF to immediately suspend the implementation of the eligibility regulations against Caster Semenya, allowing her to compete without restriction in the female category while her appeal is pending," a statement from Semenya’s lawyers said.
No time frame has been given for when a final ruling might be made, but the IAAF will make further submissions to the court, the statement said.
"The Swiss Supreme Court has granted welcome temporary protection to Caster Semenya. This is an important case that will have fundamental implications for the human rights of female athletes," added Dorothee Schramm of Sidley Austin LLP, Swiss counsel for Semenya.
The International Association of Athletics Federations (IAAF) said it had not been notified of the suspension.
"We have received no information from the Swiss Federal Court so we cannot comment at this stage," an IAAF spokesperson said.
Speaking through her lawyers, Semenya said she remains hopeful of her appeal being successful.
"I am thankful to the Swiss judges for this decision. I hope that following my appeal I will once again be able to run free,” she said.
Semenya won her last competitive 800m race at the Doha Diamond League meeting on May 3, and could potentially race again in Oslo on June 13.
Representatives of the athlete told Reuters that she has not decided on her future plans to run the 800m, the event in which she won the Olympic gold medal in 2012 and 2016.
Semenya (28) is scheduled to complete in a 2000m event in Paris on June 11, and has committed to run the 3000m at the Diamond League’s Prefontaine Classic in Stanford, California on June 30.
Testosterone is a hormone that increases muscle mass, strength and haemoglobin and the IAAF said its own research showed it gave a significant endurance advantage to athletes in the 400m to mile range.