Endometrial biopsy is an office technique for obtaining tissue samples from the lining of the uterus.
Dysfunctional uterine bleeding, postmenopausal bleeding, menorrhagia, infertility (selected cases), endometrial or pelvic infections (e.g., tuberculosis), or other situations in which a tissue diagnosis is indicated. Because it is associated with some discomfort and a small but not insignificant risk of perforation or infections and carries not only the cost of the procedure but also the cost of histologic diagnosis, this procedure is best suited for diagnosis, not screening.
Pregnancy, active pelvic inflammatory disease, significant vaginal infection, profuse bleeding, blood dyscrasia. Endometrial biopsy should generally be performed during the first 14 to 16 days of the menstrual cycle to avoid inadvertent disruption of an undiagnosed pregnancy. (Biopsies performed within 10 to 14 days beyond a temperature rise or luteinizing hormone surge will generally not interfere with implantation during that cycle.)
- Disposable endometrial sampling device (e.g., Accurette, Explora, Gynocheck, Pipelle, Z-Sampler, and others) or reusable curette (Novak or other curette)
- Sterile single-tooth tenaculum (optional)
- Sterile uterine sound (optional)
- Sterile lacrimal duct probe (optional)
- Skin preparation materials (generally an iodine-based antibacterial solution such as Betadine)
- Suitable tissue preservation/transportation medium (10% formalin solution or similar)
- Pelvic examination equipment (examination gloves, lubricant, speculum, light source)
The discomfort of endometrial biopsy may be decreased by premedicating with a single oral dose of a nonsteroidal anti-inflammatory agent given in doses usually used to treat dysmenorrhea. Although this is an office procedure, informed consent is generally considered necessary. The patient is prepared and positioned as for a routine pelvic examination. After the cervix has been visualized, it is disinfected with a topical antiseptic (e.g., Betadine).
When the patient is parous, endometrial sampling often may be accomplished without stabilizing or dilating the cervix; both of these procedures produce mild to moderate discomfort and should be avoided when possible. The sampling device is gently introduced into the uterine cavity and the depth is noted. For suction devices such as the Pipelle or Z-Sampler, the piston is withdrawn (producing a vacuum), and the curette itself is gradually withdrawn by use of a spiral or twisting motion. If an adequate tissue sample is obtained, it should be placed in fixative, completing the procedure. If additional tissue is needed, the piston may be advanced to a point just short of expelling the sample, the device again advanced into the uterine cavity, and the procedure repeated. (If tissue already obtained is to be expelled before attempting a second or subsequent try, care must be taken to avoid contact with the fixative solution or any bacterial contamination.)
Open curettes, such as the Novak, or rigid suction cannula should be gently inserted to the apex of the uterine cavity and then withdrawn in a straight line, using light pressure against the uterine wall. Tissue obtained may be removed from the opening of the curette using the point of a broken (but still sterile) wooden cotton-tipped applicator.
If significant cervical stenosis is encountered (or there is significant patient discomfort) a paracervical block using a few milliliters of 1% lidocaine (or similar) may be appropriate. The use of a lachrymal duct probe may assist in finding the path of the endocervical canal, but its fine size also increases the risk of a “false passage.”
Uterine perforation (1 to 2/1000), infection (endometrial, myometrial, pelvic). Vasovagal syncope during the procedure may occur but is generally transient.