[Controlled release vaginal dinoprostone for the induction of labour]

To study the efficacy and safety of controlled release dinoprostone (PGE2) for the induction of labour.

From March 2001 to August 2002, a total of 173 patients hospitalized for postdate pregnancy, maternal hypertension, intrauterine delayed growth, reduction of amniotic fluid, were studied. In 33 of these patients, a hydrogel strip containing 10 mg dinoprostone, inserted into the posterior fornix of the vagina and release PGE2 at constant rate of 0.3-0.4 mg/h was used.

Indications for induction, mode and time of delivery, maternal, fetal and neonatal parameters anomalies are evaluated. In 23 patients dinoprostone was used for postdate pregnancy, in 4 for maternal hypertension, in 4 for oligohydramnios and in 2 for intrauterine delayed growth. In 2 cases, the vaginal insert was removed for hyperstimulation in 1 case and for abnormal fetal heart rate in the other case. After vaginal delivery, Apgar scores and umbilical artery pH values were evaluated without anomalies. Vaginal delivery within 24 hours occurred in 51.6% of patients and medium time to delivery was 17.5 (nulliparous) and 12.3 (multiparous) hours. Only one case of uterine hyperstimulation to PGE2 was recorded, and the induction was suspended. The cesarean section rate was 12% and vaginal delivery after 24 hours was 38.7%.

The continuous release of PGE2 from the vaginal insert permits a controlled and safe induction of labour, minimal risk of hyperstimulation, fast and easy removal of drugs in cases of fetal or maternal anomalies, easy accetability for patients, but high cost.