Pelvic exams are a cornerstone of gynecological care, used in cervical cancer screening [1, 2] as well as for the diagnosis and treatment of a wide variety of conditions that affect millions of women every year [3]. For many reasons, the pelvic exam can be difficult for both physicians and patients [4]. One challenge gynecologists have struggled with since the beginning of the field [5] is the inward collapse of the lateral vaginal walls during the exam. This can obstruct the physician’s view of the cervix making a proper physical exam difficult to perform.
Recall the standard bivalve speculum is composed of a handle and two blades (also called bills), an upper (anterior) and a lower (posterior) blade, which are adjacent in the closed state (Fig. 1A). Opening the speculum separates the upper blade from the lower blade to a desired height [6]. With the patient in the standard dorsal lithotomy position (anterior abdomen facing the ceiling), opening the speculum inside the patient’s vagina causes the upper blade to retract (push) the anterior vaginal wall upward while the lower blade keeps the posterior vaginal wall down. Thus, the physician can visualize the cervix between the separated vaginal walls. However, there is nothing providing retraction for the lateral vaginal walls and preventing them from collapsing (bulging) inward. While this does not complicate the exams of many patients, the lateral vaginal walls of some patients collapse significantly enough to completely obscure the view (Fig. 1B,C,D). Difficulty in achieving cervical access leads to more maneuvering by the physician, subsequent patient discomfort, potentially incorrect diagnostic results such as missed cancer, and occasionally the need for more invasive measures (such as moving the exam to the operating room and placing the patient under general anesthesia).
Figure 1. Speculum photos: (a) labeled diagram of the Welch Allyn plastic speculum used in our experiments; (b,c,d) the physician’s view through the speculum at varying vaginal pressures as represented by our physical model during an experimental trial with a Skyn condom: (b) 0 mmHg with excellent visualization, (c) 40 mmHg (5.3 kPa) with adequate visualization, and (d) 120 (16.0 kPa) mmHg with poor visualization due to lateral wall collapse.
Those who have increased abdominal mass, such as those who are pregnant or suffer from obesity or pelvic organ prolapse, are especially likely to have vaginal walls collapse inward and obscure the examiner’s view. 89% of clinicians reported this as a major reason why cervical sampling is more difficult in patients with obesity [7]. The real-world consequences are significant. We have long known that obesity is linked to an increased risk of cervical cancer. However, a recent large study of epidemiologic data by Clarke et al demonstrated that obesity artificially “decreases” cervical precancer incidence through underdiagnosis, which consequently increases true cervical cancer incidence [8]. In other words, the connection between obesity and cervical cancer is caused by less successful screening in this population as opposed to the biological factors of obesity alone. Clarke et al estimated that 20% of the cancers could be prevented if our tests for detecting precancer (secondary cancer prevention) reached a sensitivity that was the same in our patients who are overweight or obese as it is in those who are not [8]. This decreased sensitivity of detecting precancer is likely due to the decreased ability to visualize the cervix in this population leading to an inadequate tissue sample obtained during the Papanicolaou (Pap) smear [8, 9].
Improving cervical access in patients with obesity has the potential to improve more than the aforementioned 20% of cancer disparities. It is well-documented that obesity is an independent characteristic strongly linked with decreased adherence with cervical cancer screening recommendations [10–15], even when compared to other gynecologic cancers [11, 15, 16]. While the cause of the poor adherence is multifactorial, multiple of the causes could be improved by making the pelvic exam less difficult to perform. Physicians are known to be less willing to perform pelvic exams on patients who are obese [13, 16, 17]. Physicians, in struggling to obtain good cervical access, may take longer to perform the exam and inadvertently increase patient discomfort. Anticipated pain and the anxiety surrounding it are a primary reason why many women avoid pelvic exams.
Lateral vaginal wall collapse is an issue well-known to those frequently performing gynecologic care and is often presented in educational materials teaching new trainees how to perform exams [4, 18–27]. However, the peer-reviewed, published literature characterizing the issue is limited. The available articles focus on sophisticated add-ons [28–31], novel speculum designs [5, 20], or avoiding the issue entirely by circumventing the physical exam (favoring urinary [32, 33] or vaginal self-sampling [34–38] instead) or using endoscopic visualization instead of a speculum [29, 39–41]. Despite, or perhaps because of their novelty, these methods are far from becoming the status quo for the standard office gynecologic exam. In practice, the most commonly used method to address collapse of the vaginal walls in the clinic is repurposing supplies easily found in a clinical setting, such as gloves or condoms, to act as a sheath (covering) and surround the blades of speculum. A survey of the members of American Society of Colposcopy and Cervical Pathology showed that 73% of clinicians use this technique, which is more common than sidewall retractors (59%), tenacula (72%), and patient positioning (62%) [7]. Despite their frequent use, to the authors’ knowledge, there is only one peer-reviewed article [42] published on PubMed thus far describing how to use these ad hoc solutions and none that rigorously compare the methods, though it is mentioned in passing by some other articles [4, 7, 18–20] and books [21–23].
This study aims to identify the best method for improving visualization of the cervix by decreasing lateral wall collapse using simple tools readily available in a typical clinical setting. The specific tools we considered were condoms and gloves. We tested four common condom brands, several glove sizes and material types, and multiple methods of applying the glove to the speculum. These tools were examined on a physical model that was constructed to simulate pressure applied to the lateral walls of a speculum, similar to how vaginal tissue collapses on a speculum during a pelvic exam. We also measured the effect that the materials had on restricting opening of the speculum blades as, if this effect was significant enough, the sheath can paradoxically worsen cervical visualization. These data serve as a guide for practitioners as they navigate ad hoc solutions that are commonly and informally passed along in clinical practice.