She was the first ever international champion in the women's 1500 metres, winning the gold at the 1969 European Athletics Championships in a world record time of 4:10.77 minutes.

During her career, she set personal bests of 2:04.7 for the 800 metres and 4:08.39 for the 1500 m. Born in Hořice, Jehličková established herself at national level in the mid-1960s in the 800 m, which was then the longest distance regularly by women.

[1] The longer 1500 m was introduced as a championship event for the 1969 European Athletics Championships—the first time the women's race was incorporated at a major international event—and it began to be contested more widely.

This made her the world's first international women's champion in the 1500 m.[3][4] She did not compete in the 1970 season, but returned in 1971 to repeat her middle-distance double at the national championships.

[2] She attempted to defend her 1500 m title at the 1971 European Athletics Championships, but could not compete to the same standard and finished seventh.