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The author surveys the history and present use of laminaria tents for cervix dilatation, their application for 1st and 2nd trimester induced abortions, combined use with other agents (prostaglandin F2alpha (PGF2a) and oxytocin), and complications. Laminaria tents are derived from 2 kinds of seaweed. They were 1st used in the US and Japan, and have been used in Sweden and Denmark for 50-60 years. Due to its hygroscopic quality, laminaria gradually dilates the cervix up to 12-13 mm, 15-16 hours after insertion. In a US study of 15,438 patients undergoing vacuum extraction abortion in the 1st trimester, the use of laminaria was found to result in 1/5 fewer complications than the Hegar method (which led to frequent injuries of the cervix musculature and sustained dilatation 6 weeks later). Combined use of laminaria 12-16 hours before injection of PGF2a reduced abortion time from 17.2 to 9.1 hours in 2nd trimester abortions. Combined use of intraamniotic PGF2a, iv oxytocin, and laminaria also reduced induced abortion time. Dilatation with laminaria 8-12 hours before injection of prostaglandin E2 (PGE2) in doses of .5 mg/4 hr or 1.0 mg/8 hr shortened abortion time considerably. The use of PGE2 also produced fewer gastrointestinal side effects than PGF2a. Application of laminaria the day before abortion inducement was found to significantly increase Bishop score values and produced a 75%-87% success rate even with an initial Bishop score of less than 5. Complications in the use of laminaria include difficulty of tent removal, cramps, and menstruation-like symptoms in 8-9% of patients. Laminaria is recommended for nontraumatic cervix dilatation because of reduced abortion time, minimal blood loss, high patient tolerance levels, and relatively low incidence of uterus perforation or cervix lacerations.