July 26, 2016


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How does Laminaria work?

Laminaria seems to be able to form a thick, sticky gel when it comes into contact with water. This allows laminaria to work as a bulk laxative. It also allows laminaria "tents" that have been placed inside the cervix to expand the cervix for procedures or to "ripen" the cervix and speed up the onset of labor. These laminaria tents absorb water, gradually swelling to a diameter of 1/2 inch over 4-6 hours. This swelling causes the cervix to expand, and that can bring on labor.

Are there safety concerns?

Laminaria is POSSIBLY UNSAFE when taken by mouth. It contains iodine in amounts that are high enough to harm the thyroid, the gland that uses iodine to make hormones. The average laminaria-based supplement might contain as much as 1000 mcg of iodine. Taking in more than 150 mcg of iodine per day can cause a normal thyroid to become overactive or underactive, or make an overactive thyroid worse. Some laminaria products also contain significant amounts of arsenic, a chemical element that is poisonous.

Special Precautions & Warnings:

Pregnancy and breast-feeding: The use of laminaria directly on the cervix during pregnancy or childbirth is UNSAFE. It can cause serious side effects for both mother and child, including infection, rupture of the cervix, and infant death. Taking laminaria by mouth during pregnancy is also UNSAFE because laminaria can affect hormones.

Taking laminaria by mouth during breast-feeding is LIKELY UNSAFE because laminaria might contain some poisonous chemicals.

If you are pregnant or breast-feeding, it's best to avoid laminaria.

Kidney problems: Laminaria might cause dangerously high potassium and iodine levels. Don't take laminaria if you have kidney problems.

Thyroid problems: Laminaria contains significant amounts of iodine, which might make thyroid problems worse.

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