Prevalence of endometriosis among women undergoing laparoscopic surgery for gynecological indications at Jigme Dorji Wangchuck National Referral Hospital, Thimphu, Bhutan

endometriosis, prevalence, laparoscopy, pelvic pain, infertilit y

Introduction: Endometriosis is a chronic, inflammatory disease which is characterized by the presence of endometrial like tissue outside the uterus. Endometriosis affects approximately 190 million women worldwide. The study was carried out to determine the prevalence of endometriosis among women undergoing laparoscopic surgeries at Department of Obstetrics and Gynaecology in Jigme Dorji Wangchuck National Referral Hospital (JDWNRH).

This hospital based observational study was carried out among women, who had undergone laparoscopic surgeries for gynecological indications in Department of Obstetrics and Gynaecology in JDWNRH from December 2023 to November 2024, involving 83 women who had undergone laparoscopic surgeries.

The overall prevalence of endometriosis among these women undergoing laparoscopic surgeries was 18.07%. 33.33% of women with chronic pelvic pain, 28% with infertility and 25% with ovarian cyst had endometriosis. Comparing the different indications for laparoscopic surgeries for the endometriosis, did not show significant differences (p=0.519).

This study highlights the higher prevalence of endometriosis among the women undergoing laparoscopic surgery particularly in women with chronic pelvic pain, and infertility. This high prevalence may be due to symptomatic women undergoing laparoscopy. 168 Sri Lanka Journal of Obstetrics and Gynaecology Research article

Endometriosis is a chronic, inflammatory disease which is characterized by the presence of endometrial like tissue outside the uterus 1. Endometriosis affects women of reproductive age groups and has various clinical manifestations ranging from mild symptoms to severe dysmenorrhea, dyspareunia, chronic pelvic pain, anxiety, or infertility 2. Endometriosis affects approximately 190 million women worldwide which is roughly 10% of the women of reproductive age group globally 1,3. The actual prevalence in the population is difficult because there is often delay in the diagnosis 3. However the prevalence of endometriosis varies in different regions of the globe. In Canada, the prevalence is 7%4, where as in Australia, the cumulative prevalence of clinically confirmed or suspected endometriosis in the population was 11.4% 5. A Jordanian multi-center retrospective study done for women undergoing laparoscopic surgery for various gynaecological indications found overall prevalence of 10.3% 6. The gold standard for diagnosing endometriosis is by laparoscopic visualization of lesions followed by histopathological confirmation 2. According to the type of lesions seen during the time of laparoscopy, it can be superficial peritoneal, ovarian, and deep endo- metriosis 1. Recent guidelines recommended a non- surgical (clinical) diagnosis based on symptoms, physical examinations and imaging 7. Endometriosis had remains under diagnosed due to the sign and symptoms overlapping with other gynecological conditions2 and also limited awareness, knowledge of health care providers, unknown prevalence of endometriosis in Bhutanese set up, which could have delayed the diag- nosis and delivery of effective therapy. This study aims to find out the prevalence of endometriosis in Bhutanese women undergoing laparoscopy for different gynae- cological conditions.

Study design This hospital based observational study was carried out among women, who had undergone laparoscopic surgeries for gynecological indications in Department of Obstetrics and Gynaecology in Jigme Dorji Wangchuck National Referral Hospital over a period of one year from December 2023 to November 2024. Study setting This study was conducted in the Department of Obstetrics and Gynaecology at Jigme Dorji Wangchuck National Referral Hospital (JDWNRH), which is apex tertiary hospital with high volume of patients referred for management of gynaecological disorders in Bhutan and advanced laparoscopic surgeries facility available. Study participants This study included women between 18 to 49 years, who were admitted for laparoscopic surgeries. Women under the age of 18 years and over 50 years or already in menopause were excluded from the study. Sampling technique and data collections Census sampling was done to collect all the data of the women, undergoing laparoscopic surgeries during this study period. Data were collected from patient’s admission case sheet from the maternity ward, and Operation notes from the Operation Theater using a Data collection Proforma form after obtaining informed consent. These group of women who underwent laparoscopic surgeries in the Department of Obstetrics and gynaecology for various indications were assessed for the presence of endometriosis and staging was done using the r ASMR classification scoring by the operating gynaecologists using the and r ASRM (revised American society for reproductive medicine) form 8. A written permission on the usage of r ASRM form for the data collection was granted by Elsevier Publisher on 22 nd October 2023 via email. Data processing and analysis The collected data were double checked and entered into Epidata version 3.3 (Epi Data Association, Odense, Denmark) and exported to STATA version 13 (Stata Corp, Stata Statistical Software) for analysis. Descriptive statistics such as frequency, percentage, standard deviation, and mean of the variables were calculated. Pearson Chi-square or Fisher’s exact test was used, test the association between two attributes as well as for testing of difference in proportions. Significance level was set at P value <0.05. Ethical clearance and ethics issues The ethical clearance was obtained from Institutional Review Board (IRB) of Khesar Gyelpo University of Medical Sciences of Bhutan (Ref. No. IRB/Approval/ PN/2023-019/1100, 14-Dec-2023) and administrative approval from JDWNRH was obtained prior to 169Vol. 47, No. 4, December2025 Research article commencement of the study. Informed written consent was obtained from the participating eligible patients. They were given full autonomy to decide whether to participate in the study or not with the right to reject taking part in the study after explaining to them comprehensively in the Informed Consent Form and reading out the Information Sheet.

Eighty three women had undergone gynecological laparoscopic surgeries from December 2023 to November 2024 over a period of one year were included in this study. Fifteen women were found to have endometriosis out of 83 women who underwent laparoscopic surgeries for various indications, making the overall prevalence of endometriosis of 18.07%. The mean age of the women was 34.90±8.2 years (Table 1). The majority of the women (87.95%) who had undergone laparoscopic surgery were married, 67.47% were multiparous and 54.22% were housewives (Table 1). Characteristics N (%) Age Mean age ±SD 34.90 ±8.2SD Marital status Married 73 (87.95) Unmarried 8 (9.64) Divorced 2 (2.40) Education level Non formal education 24 (28.92) Primary 10 (12.05) Lower secondary 4 (4.82) Higher secondary 32 (38.55) Tertiary 13 (15.66) Occupation Housewife 45 (54.22) Civil servant or corporate 16 (19.28) Farmer 3 (3.61) Business 14 (16.87) Student 5 (6.02) Parity Nulliparous 27 (32.53) Multiparous 56 (67.47) History of Miscarriage Yes 7 (8.43) No 76 (91.57) History of Caesarean section Yes 13 (15.66) No 70 (84.34) Table 1. Socio-demographic characteristics of women undergoing laparoscopic surgeries for gynaecological indications at JDWNRH during the period from December 2023 to 2024, N=83 170 Sri Lanka Journal of Obstetrics and Gynaecology Research article Table 2 and 3 contains the type of indications and laparoscopic surgeries that were performed on the women who were involved in this study. Majority of the indications was done for suspected ectopic pregnancies (20.48%) followed by ovarian cyst (19.28%) and family planning (18.07%). As depicted in Table 3, diagnostic laparoscopy± dye test (28.92%) was the most common surgeries done, which was followed by salpingectomy (20.48%) and tubal sterilization (18.07%). As depicted in Table 4 and 5, fifteen women were found to have endometriosis out of 83 women who underwent laparoscopy surgeries for various indi- cations, making the overall prevalence of endometriosis of 18.07%. Upon comparing the different indications for laparo- scopic surgeries for the presence of endometriosis, did not find significant differences (p=0.519). Laparoscopy indications N (%) Primary or secondary infertility 11 (13.25) Ovarian cysts 16 (19.28) Ectopic pregnancy 17 (20.48) Chronic pelvic pain 6 (7.23) Fibroids 7 (8.43) Tubal sterilization 15 (18.07) Others ¥ 11 (13.25) ¥ Includes abnormal uterine bleeding, cervical intraepithelial lesions, suspected abdominal tuberculosis and pelvic infections. Table 2. Gynaecological indications in women for undergoing laparoscopic surgeries at JDWNRH during the period from December 2023 to 2024, N=83 Indication for No endometriosis Endometriosis p-valve Laparoscopy number (%) (%) Primary or secondary 8 (72.73) 3 (27.27) P =0.519 infertility Ovarian cystμ 12 (75) 4 (25) Ectopic pregnancy 14 (82.35) 3 (17.65) Chronic pelvic pain 4 (66.67) 2 (33.33) Fibroid † 7 (100) 0 (0). Tubal sterilization 13 (86.67) 2 ( 13.33) Others¥ 10 (90.90) 1 (9.09) Type of laparoscopy surgery N (%) Diagnostic laparoscopy 24 (28.92) ± Dye test Salpingectomy or salpingostomy 17 (20.48) Tubal sterilization 15 (18.07) Ovarian cystectomy 13 (15.66) Total Laparoscopy 13 (15.66) hysterectomy (TLH) Oophorectomy or 1 (1.20) salpingo-ophorectomy Table 3. The types of laparoscopic surgeries performed among the women at JDWNRH during the period from December 2023 to 2024, (N=83) Table 4. Numbers and percentages of patients with versus without evidence of endometriosis according to the indication for laparoscopy (N=83) μ Ovarian cyst and ectopic pregnancy were merged together as adnexal mass. † Fibroid and others were merged together under others. ¥ includes abnormal uterine bleeding, CIN lesions, suspected abdominal tuberculosis and pelvic infections. 171Vol. 47, No. 4, December2025 Research article Table 4 show the details of various indications and the presence of endometriosis. Endometriosis was found in 33.33% of women undergoing laparoscopy for chronic pelvic pain followed by those who underwent diagnostic laparoscopy for infertility (28% ) and ovarian cyst (25%) (Table 4). No endometriosis was detected in those women who underwent laparoscopy for treatment of Fibroid uterus (Table 4). Endometriosis stage n (%) Stage 1 7 (46.66) Stage 2 1 (6.66) Stage 3 3 (20) Stage 4 4 (26.66) Type of lesions μ Red or flame like lesions 6 (40) Clear or vesicles 5 (33.33) White or opaque 3 (20) Endometrioma 3 (20) Table 5. Stage and type of endometriosis lesions among the women who had undergone laparoscopic surgeries for gynaecological indications at JDWNRH during the period from December 2023 to 2024, (N=15) μ Some of the women have more than one type of lesions Figure 1. Laparoscopic panoramic view showing female pelvis with the vesicle lesions of endo- metriosis (blue arrow) and endometrioma and obliteration of Pouch of Douglas (yellow arrow). Among the women , who were diagnosed with endometriosis during the laparoscopy, majority (46.66%) had stage 1, and 26.66% had stage 4 endometriosis (Table 5) as per Revised American society for Reproductive medicine classification of endometriosis. 40% of the women had red or flame like lesions, 33.33% had clear or vesicles, in some cases there were existence of more than one type of lesions as shown in Figure 1.

In our study we found that the overall prevalence of endometriosis was 18.07% among the women who had undergone laparoscopic surgeries. We observed that endometriosis was more prevalent in women with chronic pelvic pain (33.33%), followed by infertility (27.27%), and less common in women undergoing tubal sterilization. The prevalence of this study corroborated with a systemic review by Yousef Moradi et al concluded that the prevalence was 18% 9. On the contrary, the prevalence was 7% in Canada, 11.4% in Australia and prevalence of 10.3% in a multicenter retrospective study done in Jordan4,5,6. The higher prevalence in our study compared to other studies could be due to symptomatic women undergoing laparoscopic surgery with conditions potentially related to chances of endometriosis like ovarian cyst (19.28%), infertility (13.25%) and chronic pelvic pain (8.43%). The mean age of our participants was 34.90 years (SD±8.2). This is almost corresponding to the mean age of 36.1±7.2 years in Brazil (10), 34.54± 6.72 years in Northeast, India 11, 31.2 years in a study done in Nigeria12 and 29±4.3 years to a study done by Mishra, et al13. This age profile aligns with the reproductive age range, where many gynecological issues including endometriosis, are most prevalent. Among those diagnosed with endometriosis in our study, 33.33% with chronic pelvic pain(CPP) had endometriosis, which correlate with study done in Jordan, where 29.7% with chronic pelvic pain had endometriosis 6, but a study done by Taylor, et al had observed endometriosis in more than 50-80% of the CPP cases 3, and 44% in another study by Harder, et al14 . The lower prevalence compared to other studies could be due to small sample size in our study. The mechanisms underlying the association between endometriosis and chronic pelvic pain are multifaceted. 172 Sri Lanka Journal of Obstetrics and Gynaecology Research article One proposed pathway is the inflammatory response elicited by ectopic endometrial tissue. The presence of this tissue leads to local inflammation, which can sensitize nociceptive pathways and contribute to the perception of pain among women who had endo- metriosis, Prostaglandin E2 has been identified as a key player in the pathophysiology of endometriosis- related pain, as it can enhance pain sensitivity and promote the development of chronic pain syndromes 15. In this study, 27.7 % women with endometriosis had primary or secondary infertility and findings were similar to many studies6,2. Endometriosis affect fertility by altering the peritoneal environment or by distorting the pelvic anatomy. Infertility is also affected by endometriosis by causing chronic inflammation which impairs ovarian, tubal or endometrial function, leading to disorder of folliculogenesis, fertilization or implantation 2,3,14. In this study, 25% of the ovarian cystectomy were endometrioma. This finding was higher compared to a study done by Mohammad Al-Jafari, et al, where only 11.9% of the cysts were endometrioma 6. This high prevalence in our study could be due to more suspected ovarian cysts for endometrioma were offered laparoscopic surgery. The distribution of endometriosis stages showed that stage I (46.66%) was most common, followed by stage IV (26.66%). This distribution was consistent with findings by Kalpana S, et al, and Vineet V Mishra et al, who also reported that early stage endometriosis is more frequently diagnosed likely due to advance- ments in imaging and better diagnostic set up 11,13. However a proportion of our cases (Stage III, IV: 46.22%) diagnosed reflects the diagnostic delayed and other barriers to accessing specialist care in low resource setting 11,12. Strength and limitations This study was the first of its kind to assess the prevalence of endometriosis in the country and was conducted at the National referral hospital and cannot be generalized to the whole population. The other

is that the diagnosis of the endometriosis was completely based on the visual diagnosis of the endometriosis lesions which was completed dependent on observer skills of the gynecologists. Histopatho- logical confirmation of endometriotic lesions was not taken into considerations in this study.

This study highlights the higher prevalence of endo- metriosis among the women undergoing laparoscopic surgery particularly in women with chronic pelvic pain, and infertility. This high prevalence may be due to symptomatic women undergoing laparoscopy. There- fore laparoscopy remain one of the gold standard for diagnosis, staging, and surgically managing of endo- metriosis especially in cases with sign and symptoms suspected of endometriosis.

Authors would like to thank all the participants and the scrub nurses and anesthetists and the resident doctors for all the support for this study.

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