Forward Fran Kirby and midfielder Keira Walsh are out of the England squad for the friendly games against Austria and Sweden with injuries.
Chelsea's Kirby, 25, and Manchester City's Walsh, 21, picked up knocks during weekend games and will return to their clubs as a precautionary measure.
They are replaced by Chelsea's Karen Carney, 31, and City's Mel Lawley, 24.
Phil Neville's England side travel to face Austria on Thursday before playing Sweden at Rotherham on Sunday.
Kirby, who has been nominated for Fifa's Ballon d'Or award, scored in England's 1-0 win over Brazil and the 1-1 draw with Australia last month.
Since making her debut in 2005, forward Carney has earned 134 caps.
Midfielder Lawley broke into the England team just over a year ago and will be hoping to add to her nine caps.
Neville has three new faces in his squad, including former United States Under-23 forward Chioma Ubogagu, who is on loan at Brisbane Roar from Orlando Pride.
Manchester City forward Georgia Stanway and goalkeeper Ellie Roebuck have also made the squad for the first time, while captain Steph Houghton is set to win her 100th international cap.