Randomized comparison of different prostaglandin analogues and laminaria tent for preoperative cervical dilatation. World Health Organization Special Programme of Research, Development and Research Training in Human Reproduction: Task Force on Prostaglandins for Fertility Regulation.

In an eleven-centre study, 627 nulliparous subjects in the 8th to 12th week of gestation admitted for termination of pregnancy were allocated to one of five treatments to induce pre-operative cervical dilatation. The treatments were: 0.5 mg PGE2 methyl sulphonylamide; 1.0 mg PGE1 methyl ester; 30 mg 9-methylene PGE2 free acid, 0.5 mg 15-methyl PGF2 alpha; a single medium-sized laminaria tent. The results indicate that the three PGE analogues are at least equally effective as one medium sized laminaria tent and more effective than 0.5 mg 15-methyl PGF2 alpha in producing adequate pre-operative cervical dilatation prior to vacuum aspiration. It is concluded that both pre-treatment with prostaglandin analogues and laminaria tent are effective methods for preoperative cervical dilatation and both types of treatment are associated with a low incidence of side effects. Prostaglandin analogue treatment can be administered by paramedical personnel but laminaria tent insertion has to be performed by medical staff.