The remaining quarter-final ties take place on Monday, when Chelsea host Tottenham Hotspur and Birmingham City play Manchester City.
Match details
Arsenal (4-2-3-1): Van Domselaar; Holmberg (Fox 84), Wubben-Moy, Codina, Hinds; Caldentey, Little; Mead (Smith 58), Maanum (Russo 58), Kelly (Foord 58); Blackstenius (McCabe 76).
Subs not used: Borbe, Harwood, Pelova, Votikova.
Brighton (3-4-3): Nnadozie; Minami, Hayes, Vanegas; Rule, Cankovic, Symonds, Olislagers (Mpome 81); Haley (McLauchlan 89), Kirby (Noordam 81), Seike (Carla Camacho 46).
Booked: Vanegas, Cankovic.
Subs not used: Baggaley, Poulter, Rayner, Tsunoda, Tvedten.
Referee: Abigail Byrne (Bury).