After having a baby, Mikitenko returned to competition in 2006, again becoming the German champion in the 5,000 and 10,000 metres. In the
2006 European Championships, she placed ninth, one place behind long-time rival
Sabrina Mockenhaupt. In 2007, she placed second behind
Benita Johnson in the
Berlin Half Marathon, achieving a personal-best time of 1:09:46 hours. In September 2007 she made her
marathon debut at the Berlin Marathon, finishing second and qualifying for the
2008 Summer Olympics. In April 2008, at only her second international marathon, she won the women's
London Marathon in a time of 2:24:12. She withdrew from the
2008 Summer Olympics in Beijing due to hip problems causing pain whilst running on 1 August 2008. Healthy again, on 28 September, she improved her own German record with a win at the
Berlin Marathon, almost by five minutes to 2:19:19, making her number four on the women's marathon all-time list. This time is the world record in the Masters W 35-39 category. She improved the world record formerly set by Lyudmila Petrova at the London Marathon on 23 April 2006. The previous world record was 2:21:29. On 2 November 2008, Mikitenko won the jackpot prize of 500,000 $US of the
World Marathon Majors (WMM) for the best performer in New York, London, Chicago, Berlin and Boston within the last two years. After twelve competitions she was in a tie with Ethiopia's
Gete Wami with 65 points each, but the organisation voted her the winner, awarding her the prize because she had competed in only three races, compared to Wami's four. She repeated her performance at the London Marathon in 2009, finishing with a time of 2:22:11, one minute ahead of Britain's
Mara Yamauchi. Following the death of her father in July, Mikitenko struggled to find form in the buildup to the
2009 World Championships. Jurgen Mallow, director for the German athletics team, said her withdrawal was a blow for the team hosting the championships, stating that she "did not manage to hit World Championship form in the St. Moritz altitude training camp. We are very, very sad about this". Finally she participated in the October 2009
Chicago Marathon, winning with an official time of 2:26:31 and won the half-million dollar WMM jackpot for a second consecutive year. She had a seven-month lay-off after the Chicago run and decided not to run at the Paderborn 10K, which was her preparation for the
2010 London Marathon, due to sore shins. She attempted to defend her London title but her shin problems persisted and she dropped out mid-race – a fate which also befell defending men's champion
Samuel Wanjiru. She signed up for the
2010 Chicago Marathon but, despite having the fastest time in qualifying, she faded in the second half of the race and ended up in fourth place. She claimed her third consecutive WMM jackpot. She claimed victory at the 2011
Parelloop 10K in April. Running at the
2011 London Marathon, she could not keep pace with the race leaders and ended the race in seventh while
Mary Keitany won the race with a time equal to Mikitenko's best. Her season went well from there on, however: she won the Avon Frauenlauf and Berlin 10K races and was runner-up to
Florence Kiplagat at the
2011 Berlin Marathon in a time of 2:22:18 hours. She had two marathon outings in 2012. Her fastest was a run of 2:24:53 for seventh at the
2012 London Marathon, making her the fastest European in the race. She returned to the city later that August to compete in the
2012 Olympic marathon, where she placed 14th overall. She took third place at the
2013 Tokyo Marathon (a new addition to the World Marathon Majors circuit). At the Berlin Marathon 2013, she finished 3rd behind the winner Florence Kiplagat and Sharon Cherop. The time of crossing the finish line in 2:24:54 is a world record in the Masters 40 division. In 2014, she announced her retirement from professional running in a press conference in the context of the
2014 Berlin Marathon. ==Major honors==