Ripening and dilatation of the unfavourable cervix for induction of labour by a double balloon device: experience with 250 cases.

OBJECTIVE

To determine the efficacy of the double balloon device (the Atad Ripener Device) in ripening and dilatation of the unfavourable cervix for induction of labour.

METHODS

Two hundred and fifty women with unfavourable cervices (Bishop score < or = 4) underwent induction of labour with the Atad Ripener Device. Indications were pregnancy induced hypertension (n = 118), post-dates (n = 69), elective inductions (n = 23), other reasons including nonreassuring nonstress test, intrauterine growth retardation, previous caesarean section and diabetes mellitus (n = 40). The Atad Ripener Device was inserted into the cervix, the uterine balloon inflated in the internal os, and the cervico-vaginal balloon in the external os of the cervix (100 mL of normal saline to each balloon). Pressure produced by the inflated balloons caused gradual dilatation and effacement of the cervix. The Atad Ripener Device was removed 12 h after insertion, the cervix assessed again, and labour managed according to obstetrical criteria.

RESULTS

The Atad Ripener Device caused an increase in the Bishop score in all subgroups with a mean change of 4.6 (from 2.0 prior to induction to 6.6 upon removal of the Atad Ripener Device; P < 0.05). The mean time interval from insertion of the Atad Ripener Device to delivery was 18.9 h, and from removal to delivery was 6.9 h. Caesarean section was performed in 39/250 patients (16%), and the others had a normal vaginal delivery.

CONCLUSIONS

1. The double balloon device induces significant ripening and dilatation of the unfavourable cervix. 2. Induction of labour was successfully achieved following removal of the Atad Ripener Device. 3. Our caesarean section rate was low compared with rates reported for women with an unfavourable cervix induced by other methods.