Born in Castries, Spencer attended the University of Georgia in the United States.[4] She earned a bachelor's degree from Georgia in Health Promotion and Behavior, having first embarked upon a course of study in computer science. She competed at several CARIFTA Games, bringing home gold in 2001. That same year, she earned the bronze medal at the World Youth Championships in Athletics in Debrecen, Hungary, jumping 1.81 m. Earlier in the season, she sailed over 1.84 m, a Saint Lucian national record.
In 2002, she won silver medal behind Jamaica's Shaunette Davidson at the CARIFTA Games. Later that year, she finished in eighth place at the World Junior Championships with 1.83 m, far from the winner, Croatia's Blanka Vlašić. At the end of the season, Spencer made her first appearance at the Commonwealth Games, ending in 12th place with a jump of 1.74 m.
In 2003, she bettered her national record and personal best, clearing 1.86 m twice. Still a junior athlete, she made the final at the Pan American Games and ended in fifth place. In 2004, she jumped 1.88 m.
2005 was a breakthrough year for Spencer. After turning 21, she won her first major title at the Central American and Caribbean Championships by clearing a new personal best and national record of 1.94 m. This result earned her a spot in the 2005 World Championships in Athletics. She was eliminated from competition in the qualifying round, only recording 1.84 m.
In 2009, Spencer signed her first professional contract with Stellar Group, becoming the first high jumper on their roster. She repeated as Central American and Caribbean champion in Havana, Cuba and signed an endorsement deal with Caribbean telecommunications provider LIME. She was featured on the cover of the 2010 LIME Services Directory.
On 8 May 2010, in Athens, Georgia, she cleared 1.98 m to cruise to a victory with what was at the time the second-best jump in the world for the 2010 season.[5] The jump is the Saint Lucia National Record and the record for the Caribbean Community. With this result of 1.98 m, Spencer was the leading women's high jumper in the Commonwealth. At the Commonwealth Games in New Delhi, however, she needed two attempts to clear 1.88m, and eventually recorded Saint Lucia's best-ever individual finish at Commonwealth Games athletics with a bronze medal, joining Dominic Johnson, who took bronze in men's Pole Vault in 2002 in Manchester. In 2010, Spencer recorded six of the top ten best jumps of her career. She scored a victory at the 2010 CAC Games with a jump of 1.94 m and also had success on the European circuit, scoring five straight victories in Finland to scoop the 2010 Finnish Elite Games jackpot.[6]
In 2012, Spencer was awarded an Olympic Solidarity Scholarship and began training in Germany. She qualified for the 2012 Summer Olympics in London but did not make the final, finishing 19th with 1.90 m.
In 2014, Spencer made the finals at the World Indoor Championships with a new national indoor record of 1.95 m in the qualifying rounds, before finishing 7th in the final. This was her best performance at a world championship. Then, she cleared 1.96 m, her best jump since 2010, before successfully defending her Central American and Caribbean Games title in Veracruz, Mexico. She won bronze at the Commonwealth Games in Glasgow with 1.88 m. behind Australian Eleanor Patterson (1.94 m) and English jumper Isobel Pooley (1.92 m).[9] She placed fifth at the Continental Cup. She won gold at the Pan Games Festival in Mexico City, Mexico.[10] She placed second at the Organisation of Eastern Caribbean States Championships, behind Jeannelle Scheper, who also beat her at Saint Lucia's National Championships.[citation needed]
On 13 February 2016, Spencer equalled her own national indoor record in Hustopeče, with 1.95 m.[13] A month later, at the 2016 IAAF World Indoor Championships, she placed sixth with 1.93 m, three centimeters away from the gold medal, won by American Vashti Cunningham.[14] On 30 April, she jumped a World Lead (WL) of 1.95 m in Des Moines, Iowa, before attempting 2.00 m., where she failed on three attempts.[15]
On 14 May, at the IAAF Diamond League tour in Shanghai, she earned a victory with a jump of 1.94 m, on countback ahead of Uzbekistan's Nadiya Dusanova. In late June, she won the national title with 1.94 m. She competed in the qualifying round of the women's high jump at the Olympics in August and became the first Saint-Lucian athlete to qualify for the final. She finished in 6th place.[16] Back in Saint Lucia, the local population came to celebrate her performance.[17] Two weeks after the Olympics, she jumped 1.96 m at the Meeting de Paris to place second behind Ruth Beitia.[18] At the end of the season, she finishes second in the IAAF Diamond League tournament, behind Beitia again.[19]
In the 2017 season, Spencer's best jump was 1.92 m. At the 2017 World Championships in London, she was the only Saint-Lucian athlete. She failed to enter into the final, finishing in 13th place in the qualifying round.[20]
In 2018, she decided to compete in the indoor season. For her first outing, she cleared the Commonwealth Games standard with 1.90 m.[21] On 27 January, she won the high jump competition in Hustopeče with 1.93 m, the third best result in the world.[22] Three days later, she equaled her national indoor record from 2014 and 2016 in Třinec, jumping 1.95 m and claiming victory.[23] She competed at the 2018 NACAC Championships, winning a third consecutive title at 1.91m.
Retirement
After the Tokyo Olympics, Spencer announced her retirement from athletics on 31 October 2021 at the age of 37.[24]