By Rebecca H. Allen, MD, MPH, Editor
In this randomized controlled trial of 214 patients, those with a full bladder prior to Pipelle endometrial biopsy had lower first insertion failure rates without the use of a tenaculum (23.4% vs. 42.1%) compared to those with bladder status not taken into account.
Hashim E, Hong J, Woo YL, et al. Pipelle endometrial sampling with a full bladder compared with standard care: A randomized controlled trial. Obstet Gynecol 2024;144:53-59.
The authors of this study hypothesized that a full bladder would allow for easier placement of the Pipelle endometrial biopsy catheter into the uterus without the need for tenaculum application to the cervix. Pipelle endometrial biopsy sampling is performed routinely in outpatient offices for endometrial assessment.
This was a single-blind, randomized controlled trial conducted in Malaysia at a single center from July 1, 2021, to Jan. 14, 2022. Inclusion criteria were adult females needing endometrial sampling. Exclusion criteria were known cervical stenosis, gynecologic cancer, uterine anomalies, fibroids distorting the cervical canal or uterine cavity, acute cervicitis, urge bladder symptoms, “intense” anxiety, need for any local anesthesia or sedation, pregnancy, history of failed endometrial biopsy, and having taken any analgesic before the procedure. Participants were randomized in a 1:1 ratio to full bladder or routine care with bladder status not taken into account.
The full bladder arm was instructed to drink one liter of water and asked to hold their bladder for one hour or until they felt the urge to urinate. Those randomized to the standard process underwent Pipelle endometrial sampling as usual. Study staff not involved in the biopsy then measured bladder volume for all participants with ultrasound prior to the procedure. The biopsy was performed in the standard fashion, first attempting to pass the Pipelle catheter into the uterus without using a tenaculum on the cervix. If the Pipelle did not advance into the uterine cavity, a tenaculum then was applied to straighten the angle between the cervix and uterus. The primary outcome was insertion failure rate on the first attempt. Failed insertion was defined as Pipelle insertion less than 4 cm. Secondary outcomes were pain and satisfaction scores, as well as the need for tenaculum and any complications. The study had 80% power to detect a 20% difference between the two groups for Pipelle insertion failure rate.
A total of 214 individuals were recruited and randomized, with 107 participants in each group. There was no difference between the two groups in age or parity, with approximately 80% of the sample being multiparous. About one-quarter of the study population was postmenopausal. The Pipelle insertion failure rate was lower for those in the full bladder arm compared to those in the standard care arm (25/107 [23.4%] vs. 45/107 [42.1%]; relative risk [RR], 0.56; 95% confidence interval [CI], 0.37-0.84). The median visual numeric rating score for procedure pain in the full bladder group was 4 (3-6) compared with 5 (3-8) in the standard care group (P = 0.004).
Procedure duration from speculum placement to removal was 3 ± 2.4 minutes in the full bladder group compared to 4.7 ± 2.9 minutes in the standard care group (P < 0.001). As expected, bladder volume was higher in the full bladder group, with 234.7 mL compared to 28.4 mL in the standard care group (P < 0.001). After initial failed insertion, the subsequent failure rate after tenaculum application was six of 107 (5.6%) participants in the full bladder group compared to 13/107 (12.1%) participants in the standard care group (RR, 0.46; 95% CI, 0.18-1.17). There were five cervical lacerations from the tenaculum, with no difference between the two groups. There also was no difference between the two groups for inadequate endometrial biopsy samples.
COMMENTARY
An essential component of the evaluation of abnormal uterine bleeding (AUB) and postmenopausal bleeding is the office endometrial biopsy. This most commonly is performed with the Pipelle endometrial biopsy catheter. Endometrial sampling is recommended for patients with AUB who are aged 45 years and older and for younger patients with a history of unopposed estrogen exposure, risk factors for endometrial cancer, and persistent bleeding that has failed medical management.1
Endometrial biopsy with the Pipelle or other office aspirator is an accurate test for endometrial hyperplasia or cancer when an adequate specimen is obtained and the lesion occupies more than 50% of the surface area of the endometrial cavity.2 Therefore, if the test is negative, and the patient has persistent abnormal bleeding, further evaluation with a dilation and curettage hysteroscopy is warranted.
The authors of this study noted that embryo transfer and outpatient hysteroscopy procedure studies documented higher success accessing the uterine cavity with a full bladder and thought this intervention could be translated to the endometrial biopsy procedure.3,4 The full bladder can passively straighten the angle between the cervix and uterus, making it easier to traverse the internal os of the cervix. The authors hypothesized that a full bladder would make it easier to pass the Pipelle catheter into the uterus without a tenaculum. They noted that the tenaculum placement is a painful component of the biopsy procedure and, if it could be avoided, the procedure would be more comfortable for patients. Studies evaluating techniques to improve patient experience for outpatient procedures are always welcome.
The study found that, indeed, a full bladder made traversing the internal os of the cervix easier, without a tenaculum application on the cervix. In addition, procedure times were shorter and pain during the procedure was slightly less. This is a unique intervention that has advantages and disadvantages. Advantages include a shorter and potentially more comfortable procedure for the patient. Disadvantages include the waiting time for a full bladder and perhaps the patient being more uncomfortable with speculum placement, given a full bladder, although this was not documented in the study.
Most patients in my practice prefer to empty their bladder prior to a pelvic exam. Unfortunately, the study did not break the groups down into postmenopausal and premenopausal patients. It would be useful to know how many of the insertion failures occurred in each of these groups. It is possible that bladder filling only works for premenopausal patients, for example.
Other limitations include the fact that this study was done at a single center in Malaysia and may not be generalizable to patients in the United States. It would be beneficial if this study were repeated in the United States, specifically comparing efficacy in premenopausal and postmenopausal patients. That being said, this is an interesting study evaluating a practical and simple intervention for improving endometrial biopsy success.
REFERENCES
- American College of Obstetricians and Gynecologists. Diagnosis of abnormal uterine bleeding in reproductive-aged women. Practice Bulletin No. 128. July 2012; reaffirmed 2024. https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2012/07/diagnosis-of-abnormal-uterine-bleeding-in-reproductive-aged-women
- Guido RS, Kanbour-Shakir A, Rulin MC, Christopherson WA. Pipelle endometrial sampling: Sensitivity in the detection of endometrial cancer. J Reprod Med 1995;40:553-555.
- Abou-Setta AM. Effect of passive uterine straightening during embryo transfer: A systematic review and meta-analysis. Acta Obstet Gynecol Scand 2007;86:516-522.
- Celik C, Tasdemir N, Abali R, et al. The effect of uterine straightening by bladder distention before outpatient hysteroscopy: A randomised clinical trial. Eur J Obstet Gynecol Reprod Biol 2014;180:89-92.
