Brazil's Dilma Rousseff fights for her political survival

Dilma Rousseff, the first woman to be elected president of Brazil, has had her share of career ups and downs.

In March 2013, just over halfway into her first term in office, she was on a career high.

She was enjoying approval ratings of almost 80%.

Brazilians said they rated her highly for her efforts to combat poverty and hunger.

While the growth of the country's economy had already begun to slow down, unemployment was still low and incomes had not yet suffered.

It was the first time that a majority of the Brazilians consulted in a poll by the National Industry Confederation said that Ms Rousseff was doing a better job than her popular predecessor in office, Luiz Inacio Lula da Silva.

Her policies of lowering taxes on food, expanding social welfare benefits and cutting the cost of electricity were especially popular with the poor, the backbone of her Workers' Party.

Three years on, the picture is looking very different.

Ms Rousseff's approval rating are down to about 10% and she is battling to stay in office as impeachment proceedings against her are making their way through Congress.

But despite her main coalition partner, the PMDB party, turning its back on her and former allies saying they will vote for her impeachment, she has said she will not be driven out of office.

Those close to her say she is not easily cowed.

Known for her brusque manner and short temper, no one doubts her fighting spirit.

Born in 1947, she grew up in an upper middle-class household in Belo Horizonte. Her father, Pedro Rousseff, was an ex-communist and Bulgarian immigrant.

Though she had aspirations to be a ballerina, these were quickly abandoned in favour of joining the left-wing movement against Brazil's military dictatorship which had seized power in 1964.

In 1970 she was caught and imprisoned for three years. Subjected to torture including electric shocks for her role in the underground resistance, she refused to break.

During her trial, she was referred to as the "high priestess of subversion".

She first came to political prominence as the protege of Luiz Inacio Lula da Silva, who governed Brazil from 2003 to 2011.

When Lula's chief of staff, Jose Dirceu, was forced to resign and was later convicted over an illegal scheme that used public funds to pay coalition parties for political support, Ms Rousseff took over his post.

That was in 2005. She stayed in the post even as she battled lymphatic cancer in 2009.

In 2010, with Lula banned from running for a third consecutive time by Brazil's constitution, Ms Rousseff went for the top job.

She failed to get enough votes in the first round to win outright but went on to beat Jose Serra of the Brazilian Social Democracy Party in the second round with more than 56%.

Her supporters praised her commitment to social inclusion and her championing of Bolsa Familia, a social welfare scheme that has benefited 36 million Brazilians.

But her first term was not without trouble.

Many Brazilians opposed the government's backing of costly sporting events such as the 2014 World Cup in the face of continuing high levels of inequality and poverty.

In June 2013, an estimated one million protesters took to the streets during the Confederations Cup, an international football tournament which preceded the World Cup.

The protests were sparked by a rise in bus fares but escalated into nationwide unrest, encompassing a number of grievances including corruption, poor security, transport and health systems.

Ms Rousseff said she would address these concerns but maintained that the World Cup was not being financed at the expense of public services.

Despite the 2013 mass protests, Ms Rousseff still managed to beat her centre-right rival Aecio Neves to the presidency in October 2014.

Her margin, however, was narrower than four years previously and she was quick to pledge to be "a much better president than I have been until now".

Her second term has been overshadowed by a massive corruption scandal at state-run oil company Petrobras.

An investigation dubbed Operation Car Wash has uncovered evidence that Brazil's biggest construction firms overcharged Petrobras for building contracts.

Part of their windfall was then handed to Petrobras executives and politicians who were in on the deal.

Prosecutors allege that Ms Rousseff's Workers' Party partly financed its campaigns and expenses through these kickbacks.

A number of high-ranking politicians from the Workers' Party - and other parties - have been convicted over the scandal.

President Rousseff insists she had no knowledge of any wrongdoing.

But her critics, who point to the fact that Ms Rousseff served on the board of directors of Petrobras from 2003 to 2010, say they find this hard to believe.

Ms Rousseff's second term has been further hampered by economic woes, including falling oil prices, rising unemployment and a recession.

But what might eventually prove her undoing is an allegation that she manipulated government accounts to hide a shortfall in the government's budget.

She is facing impeachment proceedings over the claims that could drive her from office.

But true to her fighting spirit, she has promised to fight them all the way.