Estreja Ovadia - Mara was born in Bitola on 25 December 1923. She was born into a Jewish working-class family of parents, father Aaron and mother Sarah Ergas. The Ovadia family had five children – three sons and two daughters. Father Aaron worked as a shoemaker, bearer, various daily work, etc., while Sarah worked as an assistant in the wealthier Jewish homes of Bitola. Due to the circumstances of the family and the early loss of the father, the care of the family was first taken over by the eldest son, who, like his father, also worked as a shoemaker, but soon founded his own family and separated, after which the care of the family passed to his younger brother David. He was a member of the "Tehelet Lavan" organization and during World War II he became a member of SKOJ, thus influencing Estreja. Due to the difficult financial situation of the family, Estreja failed to continue her gymnasium education and together with her mother had to work in the rich houses in Bitola from an early age. During this time, under the influence of her brother David, who she considered an authority figure, Estreja joined the “Hashomer Hatsair” organization. According to Julie Batino, president of the women's charity association in Bitola "VICO", Estreja stood out in the circle of the active poor girls.

In 1938, with the help of the VICO organization, Estreja Ovadia, along with two other friends from Bitola, Esteja Levi and Solchi Kasorla, were sent to Belgrade to learn crafts – sewing and knitting. During her stay in Belgrade, Estreja became an activist in the trade union and youth movement, as well as a member of the Communist Youth Union of Yugoslavia (SKOJ), and took part in the March 1941 demonstrations against the Yugoslav government's policy and signing of the pact with Nazi Germany. A few days before the capitulation of the Kingdom of Yugoslavia, Estreja Ovadia and Solchi Kasorla returned to their native Bitola. After returning, she resumed her political activities and in March 1942 she became a member of the Communist Party of Yugoslavia and became involved in the preparations for armed resistance. During this period, the number of Jews from Bitola, members of the Communist Party of Yugoslavia (KPJ), increased to 30, and of SKOJ to 150 members. As a member of the KPJ, Estreja was involved in collecting so-called "red aid" – food, clothing and medical supplies for the needs of prisoners in the National Liberation War (NOB). Immediately before the deportation of the Jews from Macedonia, and until joining the partisan units, Estreja Ovadia together with Zhamila Kolonomos, Roza Kamhi, Adela Faraji and Estreja Levi illegally stayed in the tobacco store of Stojan Bogoja Siljanovski located opposite the Bulgarian police station in Bitola.

On 5 April 1943, she joined the partisan detachment "Jane Sandanski", and at the end of May 1943 on the Mount Vich in the Aegean part of Macedonia she participated in the formation of the detachment "Goce Delchev" where she was appointed political delegate of a dozen. By joining the partisan units, Estreja Ovadia was given a new "partisan" name - Mara. Until November 1943, the partisan detachment "Goce Delchev" acted on the move from Florina to Kajmakchalan, and in November 1943 the battalion "Steve Naumov" was formed from fighters from the detachment "Goce Delchev" and from other fighters, in which Estreja was a political delegate of a platoon.

At the end of 1943, the battalion moved towards Fushtani, where the main headquarters and the Central Committee of the KPM were located. In January 1944, Estreja Ovadia - Mara was a fighter in the third operational group which, together with the main headquarters and the Central Committee of the KPM had a task to move (the so-called February campaign) and via Ograzhden and Plachkovica mountains to reach Kumanovo area, at Kozjak Mountain where they were to establish a liberated (free) territory. During the February campaign Estreja, as member of the Third Macedonian Strike Brigade, was Deputy Commissioner of a company. Shortly before the ASNOM assembly was held in August 1944, Estreja was part of the military unit along with Solomon Sadikario-Mo, a young Jewish participant in the National Liberation War, and other fighters, who were tasked with attacking the Bulgarian occupying units located near Stracin. Several fighters were wounded in the battle, including Solomon-Mo, and Estreja took part in their extraction.

On 10 August 1944, the “Steve Naumov” battalion was tasked to movie from Kozjak mountain to Kozhuv mountain, and from there via Kajmakchalan to Pelister mountain, where they were to take military actions. During this movement, the military units clashed with the Bulgarian occupying units at Kajmakchalan mountain and during the attempt to break through, Estreja Ovadia - Mara is killed on 26 August 1944. She was proclaimed People's Hero of Yugoslavia on 9 October 1953.

Today, a pre-school institution in Bitola is named after Mara and there is also a street in Jerusalem in her name.