Early years

Efimova began learning to skate in 2002.^[1] She represented Finland internationally until 2014 when she moved to Moscow and switched from singles to pairs.

Partnership with Korovin

2016–2017 season

Efimova began competing with her first pair skating partner, Alexander Korovin, in 2014.^[4][5] Their international debut came in February 2016 at the Hellmut Seibt Memorial. They won the silver medal, finishing second to Italy's Valentina Marchei / Ondřej Hotárek.

Coached by Natalia Pavlova and Alexander Zaitsev in Moscow,^[6] Efimova/Korovin debuted on the Grand Prix series, placing seventh at the 2016 Rostelecom Cup in November. Later that month, the two received the silver medal at the 2016 CS Tallinn Trophy, having ranked second in the short program, first in the free skate, and second overall behind Alina Ustimkina / Nikita Volodin of Russia. After placing eighth at the 2017 Russian Championships, they took silver at the Cup of Tyrol in March 2017.

2017–2018 season

Efimova/Korovin relocated to Saint Petersburg to be coached by Oleg Vasiliev and Tamara Moskvina.^[7] In September, the pair placed fifth at their season opener, the 2017 CS Lombardia Trophy and then won bronze at the 2017 CS Ondrej Nepela Trophy a week later. In November, they took silver at the 2017 CS Tallinn Trophy behind Australia's Ekaterina Alexandrovskaya / Harley Windsor. They had no Grand Prix assignments. They finished ninth at the 2018 Russian Championships.

2018–2019 season

In September, Efimova/Korovin won their first international gold medal at their first event of the season, the 2018 CS Nebelhorn Trophy. Ranked fourth in the short program and first in the free skate, they outscored the silver medalists, Alexa Scimeca Knierim / Chris Knierim, by 1.72 points.

Efimova/Korovin competed at two Grand Prix events, the 2018 Skate America and 2018 Rostelecom Cup. In October, Efimova/Korovin won their first Grand Prix medal, silver, at the 2018 Skate America. Ranked second in the short program and third in the free skate, they won the silver medal behind their teammates Evgenia Tarasova / Vladimir Morozov. In mid-November, they competed at the 2018 Rostelecom Cup, where they finished fifth after placing fourth in the short program and fifth in the free skate.

In early December, Efimova/Korovin won their second Challenger Series gold medal of the season at the 2018 CS Golden Spin of Zagreb. Ranked first in the short program and second in the free skate, they again narrowly beat Alexa Scimeca Knierim / Chris Knierim. This time Efimova/Korovin beat them by 1.05 points. At this event, Efimova/Korovin also scored their personal best score of 183.89 points.

At the 2019 Russian Championships, Efimova/Korovin placed sixth.

2019–2020 season

Beginning the season on the Challenger series, Efimova/Korovin were seventh at the 2019 CS Nebelhorn Trophy, then won the silver medal at the 2019 CS Finlandia Trophy. They finished eighth of eight teams at the 2019 Cup of China. They placed fourth at the 2019 NHK Trophy.^[8]

At the 2020 Russian Championships, Efimova/Korovin placed fourth in the short program.^[9] The free skate was a struggle, with them placing tenth in that segment and dropping to ninth place overall.^[10]

The pair parted ways following the season.^[11]

Partnership with Bloomaert

2021–22 season

In 2021, it was announced that Efimova had teamed up with German pair skater, Ruben Blommaert and that they would be coached in Oberstorf by Florian Just.^[12][13][14]

They competed at the 2021 German Championships, the pair won the silver medal behind Minerva Fabienne Hase / Nolan Seegert.^[14]

2022–23 season

Making their international debut together, Efimova/Bloomaert won the silver medal at the 2022 CS Nebelhorn Trophy behind Deanna Stellato-Dudek / Maxime Deschamps of Canada. They then went on to win another silver medal at the 2022 CS Finlandia Trophy.^[14]

Competing on the Grand Prix series, Efimova/Bloomaert competed at 2022 Skate Canada International, however, after a hard fall on a throw in the short program, Efimova bruised her thigh and the pair withdrew from the event before the free skate.^[15] Going on to compete at the 2022 Grand Prix of Espoo, Efimova/Bloomaert won the silver medal behind Rebecca Ghilardi / Filippo Ambrosini of Italy.

At the 2022 CS Golden Spin of Zagreb, Efimova/Bloomaert finished fifth.^[14]

The pair didn't compete at the 2023 German Championships due to Bloomaert coming down with a high fever a couple of days before the event.^[15]

Regardless, they were still selected to compete at the 2023 European Championships in Espoo, Finland, Efimova/Bloomaert placed third in the short program but fifth in the free skate and dropped to fifth place overall.

Going on to compete at the 2023 World Championships in Saitama, Japan, Efimova/Bloomaert placed seventh in the short program and tenth in the free skate, finishing in tenth place overall.^[14]

Bloomaert retired from competitive figure skating following the season, citing a lack of funding from the German Skating Union as one of the main reasons.^[16]

Efimova expressed her intention to continue competing with a new figure skating partner.^[17][15]

Partnership with Mitrofanov

In June 2023, it was announced that Efimova had teamed up with American pair skater, Misha Mitrofanov, and that she would be representing the United States with him, coached by Aleksey Letov and Olga Ganicheva at the Skating Club of Boston in Norwood, Massachusetts.^[18]

They won silver at the U.S. Pairs Final behind McBeath/Parkman to qualify for U.S. Nationals. At U.S. Nationals, they were fifth after the short program and won the free skate to win the silver medal.

Pairs with Blommaert

Pairs with Korovin

Ladies' singles

Pairs with Mitrofanov for the United States

Pairs with Blommaert for Germany

Pairs with Korovin for Russia

Ladies' singles for Finland

With Mitrofanov

With Blommaert

With Korovin