From the mid-1960s, Gertrude Baumstark was one of the leading Romanian women's chess players. In Romanian Women's Chess Championships have won the nine medals: two gold (1967, 1981), six silver (1969, 1970, 1971, 1975, 1977, 1986) and bronze (1968).[2] Participant of many international women's chess tournaments, achieved best results in Lublin (1969, shared 1st-2nd place), Pernik (1973, shared 1st-4th place), Lublin (1974, 1st place), Subotica (1974, shared 2nd-3rd place), Nałęczów (1978, shared 1st-2nd place). In 1970, she was awarded the FIDE Woman International Master (WIM) title.
Gertrude Baumstark four times participated in the Women's World Chess Championship Interzonal Tournaments:
Gertrude Baumstark played for Romania in the Women's Chess Olympiads:[7]
- In 1969, at second board in the 4th Chess Olympiad (women) in Lublin (+2, =2, -4),
- In 1972, at first reserve board in the 5th Chess Olympiad (women) in Skopje (+2, =2, -1) and won the team silver medal,
- In 1974, at second board in the 6th Chess Olympiad (women) in Medellín (+7, =4, -2) and won the team silver medal,
- In 1978, at second board in the 8th Chess Olympiad (women) in Buenos Aires (+8, =4, -1) and won the individual silver medal,
- In 1980, at second board in the 9th Chess Olympiad (women) in Valletta (+2, =1, -2).
Since 2004, Gertrude Baumstark represented Germany in international chess tournaments.[8]