We take a look at notable working mothers from around the world.
Well-known working mums
MAYA ANGELOU The American writer, 83, became a single mother in her teens, and supported her son by working as a waitress and cook. She went on to become a Pulitzer Prize-winning poet, novelist, memoirist, dramatist, educator, producer, actress, historian, filmmaker and civil rights activist.
CHERIE BLAIR The British barrister, 56, has three sons and a daughter with her husband, the former prime minister Tony Blair. She became a barrister in 1976 and Queen's Counsel in 1995. She is a founding member of Matrix Chambers in London, which specialises in human rights law.
KIM CLIJSTERS The Belgian tennis player and world No. 2 has a three-year-old daughter and is one of few mums in professional tennis. After a two-year retirement, Clijsters, 28, won the US Open in 2009, becoming the first mother to win a major since Evonne Goolagong in 1980.
ANNABEL CRABB The Australian political journalist, 37, a mother of two, has won the prestigious Walkley Award for her writing in the Australian journal Quarterly Essay. She is chief political writer for ABC Online and has written two books on the history of the Australian Labor Party.
SONIA GANDHI The Indian politician, 64, and mother of two is president of the Indian National Congress. She is the daughter-in-law of the late prime minister Indira Gandhi and the widow of Rajiv Gandhi, who was assassinated in 1991. She was named the third most powerful woman in the world by Forbes magazine in 2004.
BAHIA HARIRI The Lebanese politician, 58, was elected as an MP in 1992. She has four children and is the sister of the assassinated former prime minister Rafik Hariri. Hariri is also a goodwill ambassador for Unesco, head of the Islamic Organisation for Higher Education and a member of the board of trustees of the American University in Beirut.
NICOLA HORLICK The British investment fund manager, 50, has been described as "Superwoman" in the media for balancing her high-profile career in finance with bringing up five children. After positions with SG Warburg & Co and Morgan Grenfell, she set up SG Asset Management in 1997 and Bramdean Asset Management LLP in 2005.
MICHELLE OBAMA The first lady of the United States, 47, left her job as a corporate lawyer when her husband won the US presidency. Before that, the mother of two girls worked in the nonprofit sector, including a stint as vice president for community and external affairs for the University of Chicago's medical centre.
MARGARET THATCHER The former British prime minster, 85, qualified as a barrister in 1953, the same year she gave birth to her twins, Carol and Mark. She was elected to Parliament in 1959, and was prime minister from 1979-1990. She has a life peerage as Baroness Thatcher.
VERA WANG The American fashion designer, 61, has two daughters. She was a senior fashion editor for Vogue for 16 years. Wang worked for two years as a design director at Ralph Lauren before opening her own design salon.