During 1986-1988, the Arabin-cerclage pessary was used alternatively to surgical cerclage in 58 patients for prophylactic and in 44 cases of therapeutic indications. In 5 additional patients, the pessary was applied instead of emergency cerclage. The advantages of the cerclage pessary compared to other rigid pessary types, are based on its flexibility and adjustment to the anatomic conditions of vagina and cervix. The bowl-shaped pessary is inserted with the curvature upwards and the cervix is fixed in the central opening of the cerclage pessary. Thus a constriction, reconfiguration, and elongation of the incompetent cervix is obtained as evidenced by ultrasonography. The only side effect of the pessary treatment is an increase in cervical secretion and subsequent vaginal discharge. No infectious complications occurred. In 92% of the treated gravidae the cerclage pessary could be removed after the 36th week of gestation. Cerclage pessary can be recommended as a favourable alternative to surgical procedures as prophylactic or therapeutic approach, reducing surgical treatment significantly to less than 0.5%.