Fischer was removed from the match in the 67th minute of a 3-2 victory over Angel City after a VAR review showed her pulling the hair of midfielder Madison Hammond and dragging her to the ground on an Angel City corner kick.
It resulted in Fischer's sending off and a penalty kick being awarded to Angel City, which USWNT striker Alyssa Thompson converted.
"I would like to apologize to Madison Hammond and Angel City for my actions last weekend," Fischer said in a statement issued to ESPN. "It was never my intention to be overly aggressive while defending a corner, and I sincerely regret my behavior and letting my teammates down. I accept and understand the league's decision.
"When I return to the field later this season, I plan to show that I have learned from my actions and that this moment doesn't define me as a player or the respect I have for my opponents and the game."
Fischer will not be eligible to return to the pitch until Aug. 1, while serving her suspension.