1. Tenaculum: A metal instrument used to hold and stabilize the cervix during uterine procedures.
2. Forceps: Metal instruments that have grasping loops at the end. Those made for D&E generally are used for grasping and removing the fetus in parts. Common types used for abortion are Sopher, Bierer and Hern Forceps. There also are many other types of medical forceps.
3. Osmotic Dilators (Laminaria japonica/digitata, Dilapan-S): Osmotic dilators absorb moisture and swell over time to effect chemical and/or mechanical expansion of the cervical canal. Osmotic dilators commonly are used a few hours to two days before a second-trimester abortion to open the cervix gradually to allow access to the uterus and to reduce the risk of injury to the cervix during abortion. They may be used for as little as four or five hours for earlier second trimester pregnancies to achieve a same-day procedure. Some providers use serial dilator placement, placing a new set each day until adequate dilation is achieved. Providers may choose to use one type alone, or in combination with other osmotic dilators or pharmacologic agents, such as misoprostol. The number of dilators used depends upon multiple factors, including the gestational age, time before procedure, dilator type and size, softness of the cervix, provider preference, and type of abortion planned (D&E vs. D&X).
a. Laminaria: Laminaria tents take longer to dilate the cervix and are the most commonly used osmotic dilator. They are made of dried, compressed seaweed stems that are produced in a range of diameters that range from 2-10 mm in width. When exposed to fluid, the laminaria swell to 3-4 times their dry width.
b. Dilapan-S: A synthetic rod that functions in the same way as laminaria, although it exerts more radial pressure, swells more rapidly and reaches a greater proportional diameter than laminaria. Most dilation is achieved within 4-6 hours of placement.
c. Lamicel: A sponge that is impregnated with magnesium sulfate that was used primarily for cervical softening, no longer is commercially available in the U.S.
4. Mechanical Dilators (e.g., Pratt, Hegar, Denniston): A set of rods of varying diameters that are used to dilate the cervix before an intrauterine procedure. These rods have a tapered, curved tip on either end. When mechanical dilation is necessary, providers dilate incrementally to open the cervix gradually. This means starting with a dilator with a small diameter and gradually increasing the diameter until you create an opening in the cervical canal that is large enough for the cannula and/or forceps to pass.
5. Cannula: A sterile tube that is attached to a source of suction and passed through the cervix into the uterus. Disposable plastic suction cannulae come in models that are (1) flexible, (2) rigid curved or (3) rigid straight. Plastic cannulae increase in diameter by 1mm increments from 4 to 16 mm. Non-disposable metal cannulae are used rarely.