[3] Steinhaus became a referee for the club SV Bad Lauterberg and began in the Frauen-Bundesliga after receiving DFB certification in 1999, having taken professional courses since the age of 15.

[citation needed] Steinhaus was one of the sixteen referees chosen for the 2011 FIFA Women's World Cup, where she officiated two group stage matches and the final between Japan and the United States.

[5] Steinhaus was selected to officiate the women's football gold medal match at the 2012 Summer Olympics, also between Japan and the United States.

[11] Steinhaus has been the target of abuse and controversial incidents on several occasions, including a physical confrontation from Bayern Munich manager Pep Guardiola while serving as the fourth official in a 2014 match, and an accidental groping of her breast by a player in 2010.

Fortuna Düsseldorf's Kerem Demirbay was suspended for five matches by his club after making a sexist comment towards Steinhaus, who had sent him off for a second yellow card.