What is laminaria?


Laminaria is a genus of 31 species of brown algae, all sharing the common name of the seaweed “kelp.”


  • When sterilized and formed into dry sticks, laminaria is used to dilate the cervix as part of an abortion procedure.
  • The sticks absorb body fluids and expand 3-5 times their dry-state diameter. This slow and gentle expansion causes the cervix to open.
  • An expanded cervix makes entering and exiting through the cervical opening with surgical instruments much safer for the patient.
  • The cervix’s response to laminaria varies from person to person.
  • The cervix can be cut, torn, or develop weakened muscles if an abortion is done before the cervix is adequately dilated by the laminaria.
  • A weakened cervix can become an incompetent cervix – one which no longer has the strength to support the weight of a growing baby bearing down on it during a 9-month gestational period.

Following is a description of how Warren Hern, MD, MPH inserts laminaria during an abortion:

  • The vagina is prepped with a dilute povidene-iodine solution.
  • The cervical canal is sounded (probed) to just past the internal os (opening) to determine patency and direction.
  • If necessary, a single-tooth Schroeder tenaculum is placed laterally to stabilize the cervix and to straighten the endocervical canal.
  • The laminaria is then coated with nitrofurazone ointment and placed in the endocervix with Milex laminaria forceps.
  • The vagina is packed with three to four 3X3 gauze sponges, the first one being covered with approximately 2cc of nitrofurazone ointment.