Prevalence of endometriosis in women undergoing laparoscopic surgery for various gynaecological indications at a Jordanian referral centre: gaining insight into the epidemiology of an important women's health problem

Background: Endometriosis is a considerable health challenge for women of reproductive age. Information about its prevalence in the Jordanian population is sparse. The objective of this research was to evaluate the presence of endometriosis in gynaecological patients undergoing laparoscopic surgery for various indications and to correlate the finding of endometriosis with variables, including patient demographics, obstetric history, type, and indication of laparoscopic procedure.

A retrospective cohort study involving 460 women who underwent different laparoscopic procedures for a variety of indications was conducted in the Department of Obstetrics and Gynaecology in Jordan University Hospi- tal, a tertiary referral hospital in Jordan, between January 2015 and September 2020.

The prevalence of endometriosis in this patient group was higher than that of the general population (13.7% vs. 2.5%), and the mean age at diagnosis (31.9 years) was younger than the general population’s age of peak incidence (35–45 years). It was significantly higher in women with lower numbers of pregnancies (p = 0.01) and a lower number of Caesarean sections (p = 0.05) and in those where the indication for surgery was related to decreased fertility or pelvic pain (p = 0.02). Women with high parity or where the surgery’s indication suggested normal fertility, such as family planning, were less likely to have endometriosis.

To our knowledge, this is the first Jordanian study to assess the prevalence of endometriosis in women undergoing gynaecological laparoscopy. This study suggests that the epidemiology of endometriosis in this region follows similar trends to what has been previously documented in international literature, while emphasizing the need for further research into this important women’s health issue in this part of the world. © The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom- mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Open Access *Correspondence: [email protected] 1 Department of Obstetrics and Gynaecology, Faculty of Medicine, The University of Jordan, Queen Rania Street, Amman 11942, Jordan Full list of author information is available at the end of the article Page 2 of 8Muhaidat et al. BMC Women’s Health (2021) 21:381

Endometriosis is a benign gynaecological disease char - acterized by the presence of endometrial tissue in the form of stroma and glands outside the uterus and is associated with a spectrum of clinical presentations, ranging from asymptomatic women to patients suffer - ing debilitating pelvic pain and/or fertility issues [1 , 2]. The actual prevalence in the population is difficult to ascertain because the diagnosis is often delayed or overlooked [2 ], but it is estimated that the condition affects up to 10% of women of reproductive age [3 ]. A cross-sectional population survey in the United States estimated the prevalence of diagnosed endometriosis to be 6.1% [4 ]; however, a study conducted in Italy sug - gests that only 6 out of 10 cases of endometriosis in the general population are diagnosed [5 ]. Endometriosis in Jordan, a middle-income country in the Middle East, is considered a significant pub - lic health issue affecting the quality of life of women of reproductive age [6 ]. The prevalence according to a community-based survey of women aged 15–55  years by Al-Jefout et al. was found to be 2.5% [6 ]. In another study, the prevalence of endometriosis in symptomatic young Jordanian women undergoing laparoscopy for refractory chronic pelvic pain was found to be as high as 71.4% [7 ]. Therefore, there is considerable variation in the prevalence according to the type of population sample under investigation. The two main manifestations of endometriosis can be categorized into endometriosis-related pain, such as dysmenorrhea, chronic pelvic pain, dyspareunia, dys - chezia, and infertility. Symptoms can be significantly disruptive and affect the woman’s quality of life. How - ever, 20–25% of women are affected but completely asymptomatic [8 – 10]. The age of peak incidence was found to be approximately 40 years [11, 12]. There are challenges involved in the process of diag - nosing endometriosis. First, the symptoms with which the patient presents may overlap with other conditions, such as adenomyosis, interstitial cystitis and irritable bowel syndrome. Second, the patient may consider her pain to be a normal manifestation of the menstrual cycle, which leads to a delay in seeking medical advice [1]. The gold standard for the diagnosis of endometrio - sis is direct visualization during laparoscopy [13– 15]. According to the appearance of lesions found during surgery, endometriosis can be classified into subtle, typical, cystic, or deep [16]. While this condition is commonly diagnosed during laparoscopy in patients with symptoms of endometriosis [8 , 17], it is also found incidentally in patients undergoing laparoscopic surgery for indications other than clinical suspicion of endometriosis. For example, one meta-analysis of asymptomatic patients with clomiphene-resistant pol - ycystic ovary syndrome with endometriosis found a prevalence of surgically confirmed endometriosis of 7.7% [18]. Another study of women asymptomatic for endometriosis undergoing laparoscopy for other indi - cations by Rawson found a prevalence of endometrio - sis of as much as 43.5% and demonstrated that subtle endometriotic changes were commonly found during laparoscopy in women who denied typical symptoms of the condition and reported normal fertility [19]. Several other factors have been found to be associated with the presence of endometriosis. A meta-analysis by Yong and Weiyuan suggested that a higher body mass index may be associated with a lower risk of endome - triosis [20]. This finding agrees with Ferrero et  al. who demonstrated that women with endometriosis have lower body mass indices and are less frequently obese than women who do not suffer from endometriosis [21]. Furthermore, Matalliotakis et al. found that women with endometriosis had a lower body weight and fewer prior pregnancies, elective abortions and ectopic pregnancies than women seeking care for infertility who did not have endometriosis [22]. An inverse relationship between gra - vidity and endometriosis was also found within a sub - group of subjects who had diagnostic laparoscopy [23]. This study aims to elaborate more on the prevalence of endometriosis in Jordanian women undergoing lapa - roscopy for different indications.

Study type and objective This is a retrospective cohort study involving a sample of 460 women who underwent different laparoscopic procedures for a variety of indications in the Depart - ment of Obstetrics and Gynaecology in Jordan Uni - versity Hospital, a tertiary referral hospital in Jordan, between January 2015 and September 2020. The objective of this research was to determine the prevalence of endometriosis diagnosed during lapa - roscopy and to correlate the finding of endometriosis with several variables, including age, body mass index (BMI), obstetric history, type of laparoscopic proce - dure, and indication for surgery.

Endometriosis, Laparoscopy, Jordan, Prevalence, Women’s health, Infertility, Pelvic pain Page 3 of 8 Muhaidat et al. BMC Women’s Health (2021) 21:381 Inclusion and exclusion criteria The inclusion criteria for the study were as follows: (1) female patient of reproductive age (16–50  years of age) and (2) undergoing gynaecological laparoscopy between January 2015 and September 2020. Patients were excluded from the study if they were under 16 years or over 50 years of age or if they were already diagnosed or treated for endometriosis prior to the index surgery. Data collection Patients undergoing gynaecological laparoscopy were identified from the clinical and theatre records. A total of 460 patients qualified for inclusion. Data collection was performed by retrospectively reviewing the elec - tronic medical records of the patients. The diagnosis of endometriosis was made by one of six consultants with longstanding experience in laparoscopic surgery and the diagnosis of endometriosis. Positive cases were identified based on documentation of the presence of endometri - otic lesions (subtle, typical, cystic, or deep) in the elec - tronic operative notes of the laparoscopic surgery. Where histological examination of tissue samples was avail - able, this was correlated with clinical findings, with 100% agreement between clinical and histological diagnoses. Ethical approval Ethical approval was granted by the Institutional Review Board of Jordan University Hospital prior to commenc - ing data collection. Reference number 1012021/3168. Statistical analysis We used SPSS version 26.0 (Chicago, USA) in our analy - sis. Mean (± standard deviation) was used to describe continuous variables (e.g., age and BMI). Count (fre - quency) was used to describe other nominal variables. We performed a chi-square test followed by Z-test for proportions to analyse the difference in frequency for procedure, indication, parity, miscarriages, ectopic pregnancies, and Caesarean sections between patients with and without endometriosis. We used an independ - ent sample t-test to analyse the mean difference between measurements (e.g., age and BMI) and the presence of endometriosis. We adopted a p value of 0.05 as a signifi - cance threshold. We performed a logistic regression analysis to find fac - tors associated with endometriosis on multivariate level. We included variables with p value < 0.1 on univariate analysis. We reported model classification accuracy and Nagelkerke R Square. We reported odds ratio and their 95% confidence interval (CI) for variables with p value of 0.05.

Study sample demographics A total of 460 patients who underwent gynaecologi - cal laparoscopic surgery between 2015 and 2020 were included in this study, with a mean age of 33.09 (± 7.45) years (SD). Characteristics of the included sample, including age; BMI; parity; and number of miscarriages, ectopic pregnancies, and Caesarean sections, are illus - trated in Table 1. Overall prevalence of endometriosis The overall prevalence of endometriosis in all patients was 13.7% (Table  2). Diagnostic laparoscopy was the most common procedure performed on 251 (54.6%) patients. Infertility was the most common indication in 177 (38.5%) patients. Diagnosis was made by the surgeon, identifying features of endometriosis. According to the description of lesions provided in the patients’ records, the type of endometriosis was determined (subtle, typi - cal, cystic or deep) by the surgeon during the procedure. Histopathological examination of suspected endome - triotic tissue samples was available for 13 patients (21% of those with clinical evidence of endometriosis), and where available, there was 100% agreement with clinical Table 1 Main demographic characteristics of patients included in the study sample Characteristics Minimum Maximum Mean SD Age 16 50 33.09 7.454 BMI 17 46 26.84 4.658 Parity 0 8 1.60 1.933 Miscarriages 0 16 0.59 1.620 Ectopic pregnancies 0 2 0.08 0.296 Caesarean sections 0 5 0.51 1.034 Table 2 Numbers and percentages of patients with and without evidence of endometriosis during laparoscopy *Represented as a percentage of total cases with endometriosis Evidence of endometriosis and its subtypes Number Percentage (%) No 397 86.3 Yes 63 13.7 Subtle 16 25.4* Typical 26 41.3* Cystic 17 27.0* Deep 4 6.3* Page 4 of 8Muhaidat et al. BMC Women’s Health (2021) 21:381 findings. These were patients who had prior to surgery consented to the excision of the cystic lesion or oopho - rectomy and where an intraoperative diagnosis of ovar - ian endometrioma was made based on gross appearance. This was then confirmed by histopathology for all cases. Histopathological examination was performed by one of two pathologists with special interest and expertise in gynaecological diseases. Eighteen (28.6%) patients had some form of surgical treatment (endometrioma resection, ablation of endo - metriotic lesions, or adhesiolysis at the time of primary operation), as there was previous suspicion of the pres - ence of pathology; hence, patients consented for further surgical management. For a further 10 (15.9%) patients, they were recommended to undergo further surgery to treat endometriosis as a second step procedure after obtaining proper consent and preparing the patient. In the remaining patients, the finding of endometriosis was not associated with symptoms related to the disease; it was therefore deemed incidental, not requiring surgical treatment at that stage. Tables 3 and 4 contain the types of laparoscopic sur - geries that were performed on the patient sample of this study and their indications. Upon comparing the frequency of endometriosis among different groups, we found a statistically sig - nificant difference in the prevalence of endometriosis in patients undergoing laparoscopy according to indi - cation (p = 0.020), as detailed in Table  5. On post hoc Z-test for proportions, the difference was most signifi - cant for family planning, where all 37 (100%) patients undergoing laparoscopies for family planning indica - tion were negative, and for chronic pelvic pain, where 5 (31.3%) endoscopies were positive. The condition was most commonly found when the indication for lapa - roscopy was chronic pelvic pain (31.3%), followed by infertility (16.9%), recurrent pregnancy loss (16.7%), ovarian cyst (16%), diagnosis after suspected perfora - tion (9.7%), and ectopic pregnancy (4.3%). No cases of endometriosis were identified in those undergoing lap - aroscopies for family planning purposes, such as tubal ligation. Prevalence of endometriosis according to type of laparoscopic procedure Upon comparing different procedures with the pres - ence of endometriosis, we did not find a significant dif - ference (p = 0.059). Table  6 details the frequencies. In all, 50% of those undergoing laparoscopically assisted vaginal hysterectomy had endometriosis; however, as only two patients were included in this group, it may not be very representative. Endometriosis was found in 15.9% of patients who underwent diagnostic laparos - copy, followed by those who underwent laparoscopic ovarian cystectomy (14.9%). Less frequently, the find - ing of endometriosis was associated with laparoscopic salpingectomy or salpingostomy (8.3%), and no cases of endometriosis were identified among patients who had laparoscopic oophorectomy or tubal ligation. Table 3 Types of laparoscopic surgeries performed on 460 patients Procedure Number Percentage (%) Diagnostic laparoscopy 251 54.6 Laparoscopic ovarian cystectomy 121 26.3 Laparoscopic salpingectomy/salpingos- tomy 48 10.4 Tubal ligation, bilateral or unilateral 37 8.0 Laparoscopic oophorectomy 1 0.2 Laparoscopically assisted vaginal hyster- ectomy 2 0.4 Table 4 Indications for laparoscopic surgeries performed on 460 patients Prevalence of endometriosis according to indication for laparoscopy Indication for laparoscopy Number Percentage (%) Suspected uterine perforation 31 6.7 Infertility, primary or secondary 177 38.5 Ovarian cyst accident 125 27.2 Ectopic pregnancy 47 10.2 Family planning 37 8.0 Chronic pelvic pain 16 3.5 Recurrent pregnancy loss 6 1.3 Other 21 4.6 Table 5 Numbers and percentages of patients with versus without evidence of endometriosis according to the indication for laparoscopy Indication for laparoscopy No endometriosis number (%) Endometriosis number (%) p value Suspected uterine perfora- tion 28 (90.3) 3 (9.7) 0.020 Infertility, primary or secondary 147 (83.1) 30 (16.9) Ovarian cyst accident 105 (84%) 20 (16%) Ectopic pregnancy 45 (95.7) 2 (4.3) Family planning 37 (100.0) 0 (0.0) Chronic pelvic pain 11 (68.8) 5 (31.3) Recurrent pregnancy loss 5 (83.3) 1 (16.7) Other 19 (90.5) 2 (9.5) Page 5 of 8 Muhaidat et al. BMC Women’s Health (2021) 21:381 Prevalence of endometriosis according to age, BMI, parity, number of miscarriages, ectopic pregnancies and caesarean sections As shown in Table 7, the mean age of patients with endo- metriosis was 31.97 (SD 6.55) years, while it was 33.27 (SD 7.58) years for those without endometriosis. This dif- ference was not statistically significant (p = 0.155). In this study population, no significant association was found between the patient’s body mass index (BMI) and the presence of endometriosis (p = 0.13). The mean BMI for patients with a positive finding of endometriosis was 26.4 (SD 4.3) kg/m 2, whereas it was 27.0 (SD 4.7) kg/m 2 for those without endometriosis (Table 7). Out of the 460 participants, previous obstetric history data were available for 436 patients. Endometriosis was significantly higher in patients with a lower number of parities (p = 0.008) and Caesarean sections (p = 0.035) (Table 8). Regarding parity, endometriosis was found in patients with parities up to 4, with no cases of endome - triosis found in grand multipara. The prevalence in nul - liparous women was 19%. It was 19.7% in women with a parity of one, 5.3% in women with a parity of two, 19.0% in women with a parity of 3, and 2.4% in women with a parity of 4. The prevalence of endometriosis was highest in women with no previous Caesarean sections (17.4%), with those who had from one to five Caesarean sections having a prevalence less than the overall study population. The prevalence of endometriosis was highest in those who had not suffered any miscarriages (16.6%), followed by those who had one (11.7%), three (8.3%), or two (3.6%) Table 6 Numbers and percentages of patients with versus without evidence of endometriosis according to the type of laparoscopic procedure Procedure No endometriosis number (%) Endometriosis number (%) p value Diagnostic laparoscopy 211 (84.1) 40 (15.9) 0.059 Laparoscopic ovarian cystectomy 103 (85.1) 18 (14.9) Laparoscopic salpingectomy/salpingostomy 44 (91.7) 4 (8.3) Tubal ligation, bilateral or unilateral 37 (100.0) 0 (0.0) Laparoscopic oophorectomy 1 (100.0) 0 (0.0) Laparoscopically assisted vaginal hysterectomy 1 (50.0) 1 (50.0) Table 7 Numbers and means of patients with versus without evidence of endometriosis according to the type of laparoscopic procedure Procedure No endometriosis Mean ± SD Endometriosis Mean ± SD p value BMI 27.0 ± 4.7 26.0 ± 4.3 0.130 Age 33.27 ± 7.58 31.97 ± 6.55 0.155 Table 8 Numbers and percentages of patients with versus without evidence of endometriosis according to parity and number of miscarriages, ectopic pregnancies, and Caesarean sections Number No endometriosis number (%) Endometriosis number (%) p value Parity 0 153 (81.0) 36 (19.0) 0.008 1 57 (80.3) 14 (19.7) 2 54 (94.7) 3 (5.3) 3 34 (81.0) 8 (19.0) 4 39 (97.5) 1 (2.5) 5 17 (100.0) 0 (0.0) 6 7 (100.0) 0 (0.0) 7 6 (100.0) 0 (0.0) 8 7 (100.0) 0 (0.0) Miscarriages 0 267 (83.4) 53 (16.6) 0.499 1 53 (88.3) 7 (11.7) 2 27 (96.4) 1 (3.6) 3 11 (91.7) 1 (8.3) 4 9 (100.0) 0 (0.0) 5 1 (100.0) 0 (0.0) 6 3 (100.0) 0 (0.0) 15 1 (100.0) 0 (0.0) 16 2 (100.0) 0 (0.0) Ectopic preg- nancies 0 343 (84.9) 61 (15.1) 0.051 1 29 (100.0) 0 (0.0) 2 2 (66.7) 1 (33.3) Caesarean sections 0 266 (82.6) 56 (17.4) 0.035 1 47 (90.4) 5 (9.6) 2 34 (100.0) 0 (0.0) 3 15 (93.8) 1 (6.3) 4 6 (100.0) 0 (0.0) 5 6 (100.0) 0 (0.0) Page 6 of 8Muhaidat et al. BMC Women’s Health (2021) 21:381 miscarriages. None of the patients suffering four or more miscarriages were found to have endometriosis. In rela - tion to ectopic pregnancy, the prevalence was 15.1% for those with no previous ectopic pregnancy and 33.3% for those with two previous ectopic pregnancies, whereas none of the patients with a history of one ectopic preg - nancy were found to have the condition. The association between endometriosis and the number of ectopic preg - nancies and miscarriages was not found to be statistically significant. We performed a logistic regression analysis to find fac - tors associated with endometriosis on multivariate level. We included variables with p value < 0.1 on univariate analysis. The model has a classification accuracy of 86.4% with Nagelkerke R Square of 0.094. Parity and cesarean section were significantly associated with endometrio - sis (p values of 0.036 and 0.046, respectively). Their odds ratios were 0.8 (95% CI 0.65–0.9) and 0.54 (95% CI 0.3– 0.9), respectively.

The need to investigate the epidemiology of endometrio - sis was recognized a long time ago [24]. The true preva - lence of endometriosis within any given population is difficult to determine due to a number of factors. The estimated prevalence varies according to geographical area, patient group under investigation, presence versus absence of symptoms, and method of diagnosis. Further - more, a significant number of cases may never be diag - nosed, as medical advice is not sought by the patient due to lack of symptoms or normalization of existing symp - toms [1–7]. As diagnosis is typically only confirmed after laparoscopy, data involving asymptomatic patients are likely deficient [25]. Furthermore, epidemiological studies of endometriosis face a number of methodological challenges, such as dis - ease definition, selection bias, and challenges associated with performing cohort or case control studies [16, 26]. This study found evidence of endometriosis in 13% of the 480 women undergoing gynaecological laparoscopic surgery between 2015 and 2020. This is considered higher than the prevalence in the general population (2.5%) [6]. For some of these patients, laparoscopy was indicated by conditions that are potentially related to endometriosis, such as infertility (37.1%) and chronic pelvic pain (3.3%), whereas for others, the indication did not bear an obvi - ous connection to this condition, such as family planning (7.7%). The mean age of women who were found to have endo- metriosis was 31.97 (SD 6.55) years. This is younger than the age of peak prevalence of endometriosis reported in previous studies by Eisenberg et  al. and Abbas et  al. who stated a peak prevalence in the late thirties and early forties [2, 27]. No statistically significant difference was found in the average age or BMI of patients diag - nosed with endometriosis and those who were not. This contrasts with previous studies that demonstrated that women with endometriosis tend to have a lower body mass index than the general population [21–23]. There was a statistically significant correlation between the indication for laparoscopy and the percent - age of patients who were found to have endometriosis (p = 0.02). This was highest in those where the indication was chronic pelvic pain (31.2%) and infertility (16.9%). Patients who underwent laparoscopy for recurrent preg - nancy loss and ovarian cyst accidents were also found to have endometriosis more frequently than the overall 13%. Other indication groups had a lower prevalence of endo - metriosis, with those undergoing laparoscopies for fam - ily planning purposes noticeably having a 0% prevalence of endometriosis. This compares to a study by Mahmood and Templeton who evaluated the prevalence of endome- triosis in premenopausal Caucasian women undergoing laparoscopy according to indication and found that it was 21% for those who underwent laparoscopy to investigate infertility, 15% in those with chronic abdominal pain, and 6% in women undergoing laparoscopic sterilization [28]. There was no significant difference in the prevalence of endometriosis when correlated with the type of lapa - roscopic surgery. Nevertheless, it should be noted that no cases of endometriosis were found in the patient subgroups undergoing laparoscopy for tubal ligation or oophorectomy. The prevalence of endometriosis was significantly higher in patients with lower parities and numbers of Caesarean sections. This could be explained by the known association between endometriosis and infertility [10, 29]. No significant association was found between the prevalence of endometriosis and the number of previ - ous miscarriages or ectopic pregnancies, but a noticeably high percentage (33.3%) of women who had 2 previous ectopic pregnancies were found to have endometriosis. This agrees with previous publications that suggest an association between the occurrence of ectopic pregnancy and the presence of endometriosis [30, 31].

There is to date a paucity of information regarding the true prevalence of endometriosis in Jordan. The numbers vary greatly according to the type of population exam - ined in any given study. To our knowledge, this is the first Jordanian study to assess the prevalence of endometriosis in women undergoing gynaecological laparoscopy. These patients comprise a heterogeneous group regarding the indication that prompted the procedure. Page 7 of 8 Muhaidat et al. BMC Women’s Health (2021) 21:381 The overall presence of endometriosis upon laparos - copy in this study (13%) was found to be higher than the global prevalence of this condition; however, the study sample does not represent the general popula - tion, in which the prevalence is estimated to be 2.5%, but rather a group of patients with some gynaecological complaint that requires laparoscopic diagnosis or treat - ment. We also found that, when endometriosis preva - lence is investigated in a population sample undergoing laparoscopic gynaecological surgery, the mean age of affected patients is lower than the general age of peak incidence for this condition. There is significant variation in the prevalence of endometriosis in these patients according to several factors. The findings of this study suggest that the find - ing of endometriosis in Jordanian women undergoing gynaecological laparoscopy is more commonly encoun - tered in women with lower numbers of pregnancies and in those where the indication for surgery was related to decreased fertility or pelvic pain. Women with high parities or where the surgery’s indication suggested normal fertility, such as family planning, were less likely to have endometriosis. Patient age and BMI did not seem to have a sig - nificant association with endometriosis in this study population. Endometriosis is a significant public health concern in Jordan, as it is worldwide, but its epidemiology in this region is still poorly understood. We hope that this research will add to our awareness of the prevalence of this disease in the Middle East and prompt further research in this field. This research was limited by the fact that it was a retrospective single-centre study performed on a rela - tively small sample of patients. Due to the retrospec - tive nature of the research, histological diagnosis was not available for all cases. Biopsy is not routinely per - formed in our centre to diagnose cases of endome - triosis, and as this study was retrospective, only data available in the patients’ records could be extracted and analysed. Additional surgical procedures would require informed consent, and in many cases, the finding of endometriosis was incidental in a surgical operation with an unrelated indication. However, in those where it was available, there was a 100% correlation with clini - cal findings. Further large-scale multicentre prospec - tive studies are required to deepen our understanding of endometriosis in Jordan and the Middle East. Abbreviations BMI: Body mass index; SPSS: Statistical package for the social sciences; SD: Standard deviation.

The authors would like to thank Jordan University Hospital for their help in facilitating this research. Authors’ contributions NM was responsible for the conceptualization and design of this study. NM, SS, KF, MN, NA, SAA, ME and ME contributed equally to the data collection, analysis, interpretation, and drafting of the manuscript. All authors read and approved the final manuscript. Funding No funding was required for this study. Availability of data and materials The dataset used and/or analysed during the current study is available from the corresponding author on reasonable request. Declarations Ethics approval and consent to participate This research was granted ethical approval by the Institutional Review Board (IRB) of Jordan University Hospital in accordance with the Declaration of Helsinki (reference 1012021/3170). Participant confidentiality was protected. As the study was performed by retrospectively retrieving data from hospital records and as patient information was handled anonymously, informed con- sent was not required for participation, as approved by the IRB above. Consent for publication Not applicable. Competing interests The authors declare that they have no competing interests. Author details 1 Department of Obstetrics and Gynaecology, Faculty of Medicine, The University of Jordan, Queen Rania Street, Amman 11942, Jordan. 2 Depart- ment of Family Medicine, Faculty of Medicine, The University of Jordan, Amman 11942, Jordan. 3 Department of Ophthalmology, Faculty of Medicine, The University of Jordan, Amman 11942, Jordan. 4 Faculty of Medicine, The University of Jordan, Amman 11942, Jordan. Received: 2 June 2021 Accepted: 28 October 2021

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