Pre-induction cervical ripening: comparing between two vaginal preparations of dinoprostone in women with an unfavorable cervix.

OBJECTIVE

Prostaglandin E2 (PGE2-Dinoprostone) is accepted for both ripening of the cervix and induction of labor. As conflicting data exist concerning the efficiency and safety of different treatment modalities, we aimed to compare slow-release vaginal insert PGE2 with serial vaginal tablets of PGE2 for cervical ripening and induction of labor.

METHODS

A retrospective cohort study comparing all pregnancies who underwent induction of labor by either a single slow-release vaginal insert of 10 mg PGE2 (study group) to a historical control group of women who were treated with serial administration of 3 mg vaginal PGE2 tablets in a 2:1 ratio, matched by parity.

RESULTS

Overall, 639 women were enrolled (213 treated with PGE2 tablets and 426 with slow-release vaginal inserts). Vaginal insert was associated with shorter initiation-to-ripening interval (12.4 ± 7.7 versus 18.6 ± 15.2 h, p < 0.001) and a higher rate of delivery within 24 h (61.5 versus 51.6%, p = 0.018). Vaginal insert was associated with an increased rate of tachysystole (8.0 versus 3.1%, p < 0.01); however, the rates of cesarean section or operative delivery due to non-reassuring fetal heart rate (NRFHR) were similar. On multivariable analysis, slow-release vaginal insert was independently associated with a higher rate of delivery within 24 h (OR 1.50, 95% CI 1.04-2.18).

CONCLUSION

Slow-release PGE2 vaginal insert achieves cervical ripening and subsequently delivery over a shorter time period than PGE2 tablets, without increasing uterine hyperstimulation rate.