Kim Clijsters of Belgium hits a return to Marion Bartoli of France at the U.S. Open tennis tournament in New York on Sept. 2, 2009.KEVIN LAMARQUE/Reuters
Several high-profile female athletes have achieved success in sports after becoming mothers:
Fanny Blankers–Koen the Netherlands, track and field
Won four gold medals at the age of 30 in the 1948 London Games. The mother of two won four of the nine women's events, competing in 11 heats and finals in eight days. She was pregnant with her third child at the time. Throughout her successful career – setting or equalling 12 world marks, winning 58 Dutch championships – she dominated long jump, high jump, sprint and hurdling events. Her incredible feats earned her the nickname "the Flying Housewife." She passed away in 2004, aged 85.
Oksana Chusovitina Germany, gymnastics
Competed at the 2000 Sydney Games 10 months after delivering son Alisher. She is the only female gymnast ever to compete in five Olympic Games after winning silver for Germany on vault in 2008.
Kim Clijsters Belgium, tennis
Retired when she gave birth to her daughter, Jada, in 2008, but returned to be a dominant force on the women's professional tour in 2009. She won the U.S. Open Championship as a wild card and became the first mother to take a major since Yvonne Goolagong Cawley. It was the first of three majors Clijsters would win as a mom – compared with a single major won prior to motherhood.
Becky Kellar Canada, hockey
Earned a gold medal at the 2006 Turin Games just 16 months after having a baby boy, then had a second before winning gold again in 2010.
MC Mary Kom India, boxing
Delivered twin boys in 2007, and after nearly two years off, won her fourth world championship. She followed up with a fifth in 2010, the only female boxer to win a medal in the first six women's worlds. Many family members begged her to retire, fearing she would take punches to her midsection, where she had undergone a cesarean section. She makes her Olympic debut in London at age 29.
Ann Peel Canada, race walking
Won two Pan American Race Walking Cups and was twice second in indoor world championships as well as second in the 1987 Pan American Games. Competed one month after giving birth in 1991 to convince then-Canadian minister of state for sport Marcel Danis to remedy an athlete-funding policy that cut off money from pregnant athletes.
Jenny Potter U.S., hockey
A four-time medalist, played hockey through her first trimester of two pregnancies, gave birth in January of 2001 and January of 2007, waited six weeks both times and began training for the women's world hockey championship, held each April.
Paula Radcliffe Britain, marathon
Mother to daughter Isla, 5, and son Raphael, 2, Radcliffe has three victories in the London Marathon, one in the Chicago Marathon – and two in the New York City Marathon since becoming a mother. The London Olympics will be her fifth and last Games.
Wilma Rudolph U.S., sprint
Less than two years after the birth of her first child, Rudolph won three gold medals at the 1960 Rome Olympics in the 100 metres, 200 metres and 4X100 metres relay, also setting two world records.
Dara Torres U.S., swimming
In 2006 at the age of 39, Torres gave birth to her daughter, Tessa, then returned to the pool and at 41 won three silver medals at the 2008 Beijing Olympic Games, in the 4X100 metres freestyle relay, 50 metres freestyle and 4X100 metres medley relay. The twice-divorced mother said her daughter helped rejuvenate her.
Catriona Matthew Scotland, golf
A four-time LPGA and four-time European Tour winner, her first and only major came in 2009 in the Ricoh Women's British Open at Royal Lytham & St. Annes, 11 weeks after the birth of Matthew's second daughter, Sophie.