Anaphylaxis following laminaria insertion rarely occurs but may be a life-threatening condition. Laminaria tents, prepared from natural sea kelp, are commonly used prior to elective termination of pregnancy to achieve cervical dilatation. We report herein two cases of anaphylaxis caused by IgE-mediated hypersensitivity to laminaria. Two women, each of whom had undergone at least one previous abortion where a laminaria had been utilized, developed anaphylactic reaction following laminaria insertion. The reaction included urticaria, nausea, breathing difficulty, and hypotension. The patients subsequently underwent skin testing and measurement of serum specific IgE level to laminaria extract, and were shown to elicit positive responses to laminaria. The implication and impact of laminaria allergy on gynecologic procedures are significant and this allergy should be included in the list of differential diagnoses for hypersensitive reaction in gynecologic procedures.