A laminaria stick or tent is a thin rod of dried laminaria, a kelp species. Laminaria sticks are used in obstetrics to slowly dilate the cervix to induce labor and delivery or for surgical procedures including abortions. The rods are inserted into the cervix, and over the course of several hours, they slowly absorb water and expand, dilating the cervix and prompting labor.
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Laminaria stick Wikipedia(Text) CC BY-SA