A speculum is a hinged, two-bladed instrument that holds the vaginal walls apart so a healthcare provider can see the cervix. The blades are inserted into the vagina while closed, then gradually opened and locked into position, creating a clear line of sight for exams like Pap smears, biopsies, and visual inspections.
Basic Mechanics of the Speculum
The standard speculum, often called a “duckbill” speculum because of its shape, has a few key parts: two curved blades, a hinge or pivot joint connecting them, a handle, and a locking mechanism. The blades start pressed together, forming a narrow, rounded shape that can be inserted into the vaginal canal. Once inside, the provider squeezes the handle to separate the blades, which pushes the vaginal walls apart in opposite directions. A thumbscrew or ratchet mechanism then locks the blades at the desired width so the provider can work hands-free.
The locking feature is important because it means the speculum stays open on its own. This frees the provider to collect cell samples, take photographs, or perform other tasks while maintaining a clear view of the cervix. When the exam is finished, the provider releases the lock, gently closes the blades, and withdraws the instrument.
What Happens During Insertion
Before inserting the speculum, your provider will warm it. A cold speculum causes muscles to tense up, making the exam more uncomfortable. Warming methods include rinsing it in warm water, holding it under a lamp, or keeping it on a heating pad. A water-based lubricant is applied to the lower blade to reduce friction.
You’ll typically lie on your back with your knees bent and apart. Some providers raise the head of the exam table to about 40 degrees, which naturally relaxes your abdominal and pelvic muscles and lets you maintain eye contact with the provider. Stirrups are common but not always necessary. An alternative called the M-shaped position has you lying back with your feet flat on the table and knees apart, no stirrups needed. Side-lying positions also work for people who find being on their back uncomfortable.
The provider inserts the closed speculum at roughly a 45-degree downward angle, aiming toward the lower back. This angle follows the natural tilt of the vaginal canal and keeps the instrument away from the urethra, which is sensitive. They apply gentle downward pressure during insertion, directing the blades along the back wall of the vagina. Once the speculum reaches the right depth, usually just a few inches, the blades are slowly opened until the cervix comes into view.
Why There Are Different Types and Sizes
Not everyone’s anatomy is the same, so speculums come in a range of sizes and shapes. The two most common types are the Pederson and the Graves.
- Pederson speculum: Has narrower, flatter blades. It’s commonly used for people who are sexually active but haven’t given birth vaginally. It comes in multiple sizes, from extra-small to medium.
- Graves speculum: Has wider, more curved blades. It’s a better fit for people who have given birth vaginally, since the vaginal canal tends to be wider and the walls more elastic afterward. It’s also the go-to choice for procedures like colposcopy and biopsy, where a larger field of view helps. Graves speculums also come in a range of sizes.
Blade dimensions vary depending on the manufacturer and model, but to give you a sense of scale, small blades are roughly 70mm long and 25mm wide (a little under 3 inches by 1 inch), while larger blades can be around 90mm long and 40mm wide. Your provider selects a size based on your anatomy, and choosing the right one is a big factor in comfort.
How Providers See Inside
Once the speculum is open, the provider needs light. Traditionally, an external lamp was aimed between the patient’s legs, which required constant repositioning. Modern speculum systems now come with built-in light sources attached to or integrated into the instrument itself. These provide direct illumination right at the exam area, giving the provider a brighter and more consistent view without having to fuss with lamp placement.
Some clinical settings also attach small cameras to the speculum or use a separate magnifying instrument called a colposcope for a closer look. This is common during follow-up exams when abnormal cells have been found on a Pap smear.
Why It Can Feel Uncomfortable
The speculum stretches tissue that isn’t used to being held open, so some pressure and mild discomfort are normal. Several things influence how it feels. Muscle tension is the biggest factor. Anxiety, cold instruments, and holding your breath all cause the pelvic floor muscles to tighten, which makes insertion harder and more noticeable. Slow, deep breathing and consciously relaxing your legs can make a real difference.
The provider’s technique matters too. Inserting at the correct downward angle avoids bumping the urethra, which is one of the sharper discomforts people report. Emptying your bladder before the exam also helps, since a full bladder puts extra pressure on the vaginal walls and makes the whole area more sensitive. If you’ve experienced pain during past exams, telling your provider beforehand gives them the chance to use a smaller speculum, extra lubricant, or a slower approach.
Newer Designs on the Horizon
The basic duckbill design has been in use since the 1870s, when Thomas Graves updated an earlier instrument into the two-bladed model still found in most exam rooms. Engineers at the University of California, Irvine, developed a newer device called the OneSpec that takes a fundamentally different approach. It’s shaped and sized like a tampon at insertion, starting at about half an inch in diameter, then expands outward in a full 360-degree circle up to two inches. This design eliminates the two-point pressure that traditional blades create and improves visibility by opening the view in all directions rather than just top and bottom. It’s also quieter, removing the metallic clicking sound that many people find anxiety-inducing during exams.