The Quins had held the upper hand against the university side in two previous meetings, having lost in last year's cup final and in a league encounter prior to Christmas.
But a fully committed display by UWIC ensured revenge was gained in a highly physical battle. Both sides worked hard for territory and possession early on and despite being down to 14 players after hooker Rhian Bowden was sin binned, UWIC opened the scoring with a penalty by full-back Aimee Young but this was quickly cancelled out through a Non Evans penalty.
Despite UWIC dominating possession and territory in the first half, it was England international Amber Penrith who crossed the line for Quins after a good backline handling sequence. The try was converted by Evans, bringing the half time score to 10-3.
UWIC responded early in the second half when fly half Mared Evans sliced through the Quins defence and offloaded to centre Rachel Poolman who touched down and with Evans adding the conversion, the scores were tied at 10-10.
UWIC were punished for playing high risk attacking rugby in their own half when Quins centre Hayley Baxter intercepted a pass to score under the posts which was again converted by Non Evans to edge Quins 17-10 in front.
UWIC grew in confidence as the game developed with the platform coming from impressive set-piece domination led by loose head Hannah Roberts, hooker Bowden and tight head Lowri Harries.
Mared Evans reduced the arrears with 10 minutes remaining with a well struck penalty to leave the match in the balance.
UWIC threw caution to the wind, playing attacking rugby at every phase, with back row players Lisa Newton and Carys John dominating the contact area. Eventually the domination paid when the dominant pack drove the scrum and was awarded a penalty try which again was converted by Mared Evans, giving UWIC the lead by 17-20.
The university side held on for the remaining few minutes, with great control shown by scrum half Amy Day. This victory against a very skilful Quins team will give the UWIC squad great confidence heading into the knock-out stages of BUCS and gives them a chance to fight for the Welsh Cup against Neath Athletic in April.
UWIC head coach Kylie Wilson commented after the game: "I am so pleased that the girls put in an 80 minute performance against quality opposition. They remained committed to the style of rugby we at UWIC want to play and that proved enough to win the game".