{"paper_id":"d9262c0c-ec5f-40f6-bc9c-288f68c9e075","body_text":"Title: Anti-Müllerian hormone is decreased in women with superficial peritoneal endometriosis 1 \nand associated with an elevated inflammatory profile 2 \n 3 \nRunning title: Infertility in peritoneal endometriosis  4 \n 5 \nAuthors  6 \nMeaghan J Gri@iths 1, Martha E Brown1, Douglas A Gibson 1, Frances Collins1, Cheryl E Dunlop2, 7 \nPhilippa TK Saunders1, Andrew W Horne1 8 \n1 EXPPECT Edinburgh, Centre for Reproductive Health, Institute for Regeneration and Repair, 9 \nUniversity of Edinburgh, UK 10 \n2 Edinburgh Fertility Centre, Royal Infirmary of Edinburgh, UK 11 \n 12 \nORCID IDs 13 \nMJG  0000-0001-9791-5490 14 \nMEB  0009-0009-8447-2614 15 \nDAG  0000-0002-9949-1983 16 \nCED  0009-0004-0104-2349 17 \nPTKS  0000-0001-9051-9380 18 \nAWH  0000-0002-9656-493X 19 \n 20 \n  21 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \nNOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.\n\nAbstract 22 \nStudy question:  How are  the levels of anti -Müllerian hormone  and inflammatory cytokines  23 \ninfluenced by superficial peritoneal endometriosis (SPE)?  24 \nSummary answer: Fertility metrics (Endometriosis Fertility Index (EFI), and serum anti-Müllerian 25 \nhormone (AMH) levels) are reduced in women with SPE. Simultaneously, inflammatory markers 26 \nare elevated in the circulation and local pelvic peritoneal microenvironment , with distinct 27 \nchanges in each compartment.  28 \nWhat is known already:  Between 25-40% of women with endometriosis experience infertility , 29 \nthough the mechanisms behind this are poorly understood. Ovarian endometriosis is known to 30 \ndecrease AMH levels and contribute to infertility, but little is known about SPE-associated 31 \ninfertility, and how the peritoneal microenvironment might play a role in infertility for women with 32 \nSPE. 33 \nStudy design, size, duration: Venous blood samples from women with suspected endometriosis 34 \nwere collected prior to diagnostic laparoscopy (n=105). Pelvic peritoneal fluid was also collected 35 \nfrom a subset of the women (n= 38). The Endometriosis Fertility Index (EFI) was calculated after 36 \nsurgery, and levels of AMH and inflammatory cytokines measured by ELISA or multiplex Luminex.  37 \nParticipants/materials, setting, methods:  Based on their surgical findings, women were 38 \nclassified as no endometriosis observed (no endo; n=39), superficial peritoneal lesions only 39 \n(SPE; n=43), or SPE with an ovarian endometrioma (SPE+OE; n=23). Women were further grouped 40 \nby their use of hormone treatments to manage their endometriosis symptoms (no endo : no 41 \nhormones n=14, hormones n=25; SPE : no hormones n=20, hormones n=23; SPE+O E: no 42 \nhormones n=17, hormones n=6). Data are described as either mean ± standard deviation, or 43 \nmedian [interquartile range]. 44 \nMain results and the role of chance: SPE+OE women were older (3 1.73±6.31) than SPE 45 \n(27.77±6.14; p=0.04) and control women (27.65±5.81; p=0.02). Both SPE and SPE+OE groups had 46 \nlower EFI scores compared to women with no endometriosis (no endo 9.41±0.50; SPE 8.63±1.11 47 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\np=0.04, SPE+OE 6.95±1.60 p<0.0001). Serum AMH levels were lower for SPE alone (p=0.009) and 48 \nSPE+OE women (0.73ng/mL [0.32, 1.19], p=0.002) compared to women with no endometriosis 49 \n(1.15ng/mL [0.75, 1.94] ) when accounting for age. When also accounting for hormone use , 50 \nwomen with SPE+OE had lower AMH levels compared to women with no endometriosis (p=0.02), 51 \nwhile women with SPE alone did not (p=0.069) . Moreover, women with SPE not using hormones 52 \nhad elevated serum IL-17 (4.45pg/mL [4.26, 4.88] vs 3.84pg/mL [ 3.54, 4.19], p=0.02) and TNF-a 53 \ncompared to women with no endometriosis (4.28pg/mL, [3.37, 5.88] vs 1.99pg/mL, [1.49, 3.43], 54 \np=0.03), while pelvic peritoneal fluid levels of IL -23 were elevated in women with SPE not using 55 \nhormones (212.4pg/mL, [184.0, 244.5] vs 121.3, [46.37, 147.60], p=004). These di@erences were 56 \nnot significant in women using hormones.  57 \nLimitations, reasons for caution: Due to the limited sample size of women not using hormones, 58 \nwe were unable to determine if serum IL-17 or TNF-a, or pelvic peritoneal IL-23 levels negatively 59 \ncorrelated with AMH levels.   60 \nWider implications of the findings:  Women with SPE, with or without OE, have lower AMH levels 61 \n- indicative of reduced ovarian reserve - compared to women without endometriosis. Among 62 \nthose with SPE, diminished AMH was associated with increased serum levels of IL-17 and TNF-α 63 \nand elevated IL-23 in the pelvic peritoneal fluid, suggesting compartment-specific inflammatory 64 \nprofiles. Notably, changes to circulating inflammatory cytokines were di@erent  when use  of 65 \nhormonal therapy  was taken into account , highlighting such treatments may modulate 66 \ninflammation linked to endometriosis.  Taken together, our data support the need for further 67 \ninvestigation into inflammation as a potential mechanism underlying infertility in women with 68 \nSPE in the absence of OE. 69 \nStudy funding/competing interest(s): Deanery of Clinical Sciences Funding Challenge, 70 \nUniversity of Edinburgh awarded to MJG.  71 \nTrial registration number: University of Edinburgh Lothian Ethics Committee REC 20/LO/1298. 72 \n 73 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nKey words (up to 10) 74 \nEndometriosis, infertility, AMH, ovarian reserve, superficial peritoneal endometriosis, 75 \ninflammation, cytokines 76 \n  77 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nIntroduction 78 \nEndometriosis is a chronic, hormone-dependent neuroinflammatory disease where 79 \nendometrial-like tissue grows outside the uterus. It a@ects about 10% of reproductive age women 80 \nworldwide, and currently, there is no cure (As-Sanie, Mackenzie et al. 2025). The four subtypes of 81 \nendometriosis - superficial peritoneal (about 80% of cases), deep, ovarian (endometriomas), and 82 \nextrapelvic - can occur alone or together. Superficial peritoneal endometriosis (SPE) is typically 83 \nlocated on the  surface of abdominal or pelvic organs  and the pelvic wall . Deep endometriosis 84 \ninvades pelvic tissues or organs, like the bowel or bladder. Ovarian endometriomas (OE) are cysts 85 \nlined by endometrial tissue within the ovary. Extrapelvic endometriosis involves lesions outside 86 \nthe pelvis and can a@ect many organs, including the diaphragm, thoracic organs, or even the 87 \nbrain. 88 \nA frequent symptom for up to half of women with endometriosis is infertility. Alone, infertility has 89 \ndetrimental impacts on mental health and quality of life for those wanting to conceive, which is 90 \nfurther increased by endometriosis (Mori, Zaia et al. 2024) . Clinically, both endometriosis and 91 \ninfertility su@er delays with diagnosis and a lack of e@ective, accessible, treatment options.  92 \nIn international guidelines for endometriosis, it is recommended women with SPE consider 93 \nsurgery to remove SPE lesions based on evidence that this may  improve spontaneous pregnancy 94 \nrates within the first 12 months post-surgery (NICE 2017, Becker, Bokor et al. 2022). In many UK 95 \ncentres, the waitlist for a diagnostic laparoscopy for endometriosis is two or more years  96 \n(Endometriosis UK 2024, Royal College of Obstetricians and Gynaecologists 2024) . For these 97 \nwomen, assisted reproductive technologies  (e.g. IVF) provide one potential solution , although 98 \nthis is also subject to access to NHS provision  (in the UK), and is costly. A 2023 study found 3.2 99 \nmillion women of reproductive age in England had no or limited access to a fertility clinic in their 100 \narea of residence , while the  highest household income  areas had the best access to fertility 101 \nclinics (Jones, Peri-Rotem et al. 2023) . Importantly, there is a group of women  who are only 102 \ndiagnosed with endometriosis when they  attend fertility clinics when seeking to become 103 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\npregnant and the majority of these are cases of SPE  (Van Gestel, Bafort et al. 2024) . If these 104 \nwomen are of advanced maternal age, it is unlikely that they will want to wait several years for a 105 \nlaparoscopy to remove the endometriosis in the hope it may e nable them to conceive 106 \nspontaneously. To provide better and more equitable options for these women , we must better 107 \nour understanding of the mechanisms behind how SPE contributes to infertility. 108 \nThe Endometriosis Fertility Index (EFI) predicts post-surgery pregnancy success for women with 109 \nendometriosis based on the surgeon’s assessment of damage to Fallopian tubes, fimbria and 110 \novaries, endometriosis staging score, patient age, and pregnancy history  (Adamson and Pasta 111 \n2010). Since its inception, it has been validated in a variety of settings and shown to accurately 112 \npredict non -IVF pregnancy success for women with endometriosis post -surgery (Tomassetti, 113 \nGeysenbergh et al. 2013, Garavaglia, Pagliardini et al. 2015) . It has also recently been shown it 114 \ncan be accurately completed  without surgical intervention (Tomassetti, Bafort et al. 2021) . 115 \nHowever, to date, i ts utility has been limited to testing on combined datasets containing all  116 \nsubtypes of endometriosis. 117 \nIn clinics o@ering  assisted reproducti ve technologies , circulating levels of anti -Müllerian 118 \nhormone (AMH) are typically measured to predict the capacity of the ovary to respond to hormone 119 \nstimulation and production of viable oocytes. Notably, AMH is an indirect marker of the quiescent 120 \npool of primordial follicles that make up the ovarian reserve and is produced by the proliferating 121 \ngranulosa cells surrounding an oocyte during development, prior to ovulation. AMH has 122 \npreviously been measured in cohorts of endometriosis patients, most commonly those with 123 \novarian endometrioma. In these cases, AMH often decreases after surgical removal of an 124 \nendometrioma via cystectomy (Wang, Liu et al. 2020, Muraoka, Osuka et al. 2021, Sarbazi, Akbari 125 \net al. 2021, Fakehi, Davari Tanha et al. 2022, Mansouri, Safinataj et al. 2022, Shi, An et al. 2022, 126 \nTang and Li 2022, Crestani, Merlot et al. 2023). Some reports suggest AMH levels increase again 127 \nduring follow-up periods, however they never return to pre-surgery levels (Kostrzewa, Wilczyński 128 \net al. 2019, Sadullayev and Medvediev 2022). To date, only one study has reported AMH levels in 129 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\na cohort of women with SPE , demonstrating no change in AMH  compared to age -matched, 130 \npopulation controls  (n=62 in each group)  (Lessans, Gilan et al. 2023) .  In another study , 40 131 \nexpectantly managed women (no surgical intervention to treat their ovarian endometriosis) were 132 \nreported to have AMH levels which declined faster than control women without endometriosis  133 \n(Kasapoglu, Ata et al. 2018)  providing the strongest evidence to date that there is a mechanism 134 \nby which endometriosis drives infertility.  In the current study, serum AMH was measured in a 135 \ncohort of women with SPE , and levels were  compared to both women without endometriosis 136 \n(confirmed absence of lesions by laparoscopy), and a group of women also with an 137 \nendometrioma (SPE+OE), to investigate how AMH may be altered by SPE. Additionally, we 138 \nmeasured systemic and peritoneal inflammation as potential mechanisms driving 139 \nendometriosis-associated infertility and associated changes to AMH levels.  140 \n 141 \nMaterials and Methods  142 \nEthical approval 143 \nParticipants were recruited in South-East Scotland between October 2015 and July 2023 from the 144 \nRoyal Infirmary of Edinburgh (NHS Lothian, REC 20/LO/1298) and gave informed consent to be 145 \ninvolved in the study and for biospecimens to be collected during surgery. 146 \n 147 \nParticipants samples 148 \nParticipants were scheduled to undergo diagnostic laparoscopy for suspected endometriosis, or 149 \nother gynaecological procedures (‘no endo’ group only).  A venous blood sample was taken prior 150 \nto surgery, and where possible, a peritoneal fluid sample collected during surgery.  151 \nBiospecimens were processed in accordance with  WERF EPH ect protocols  (Rahmioglu, 152 \nFassbender et al. 2014) . Serum was collected from whole blood samples via centrifugation at 153 \n2500g for 10 minutes at 4°C and aliquots stored at -80°C. Peritoneal fluid was similarly processed 154 \nby centrifugation at 900g for 5 minutes at 4°C and aliquots stored at -80°C.  155 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\n 156 \nClinical information 157 \nParticipants were categorised by an endometriosis surgeon according to surgical findings; no 158 \nendometriosis (no lesions observed ; no endo ), superficial peritoneal endometriosis (only 159 \nsuperficial lesions present ; SPE ), or superficial peritoneal endometriosis with an ovarian 160 \nendometrioma (SPE+OE) (Table 1). Exclusion criteria included participants currently pregnant or 161 \nbreastfeeding, known reproductive malignanc ies, and previous history of endometriosis, 162 \nspecifically endometrioma. Current use of  hormonal treatment s to manage endometriosis 163 \nsymptoms was used to stratify samples. Hormone treatments included the combined oral 164 \ncontraceptive pill (COCP), progesterone only pill (POP), Depo-ProveraTM, levonorgestrel 165 \nintrauterine system (LNG-IUS), NexplanonTM implant, norethisterone, or a contraceptive patch . 166 \nTheir prevalence of use in this cohort is summarised in Table 1. The Endometriosis Fertility Index 167 \n(EFI)  was calculated for each participant as previously described (Adamson and Pasta 2010).  168 \n 169 \nAMH ELISA  170 \nSerum samples were diluted 1:10 and assayed in duplicate using the human picoAMH ELISA (AL-171 \n124-r, Ansh Labs, United States) according to manufacturer’s directions. Absorbance was read 172 \nusing Clariostar plate reader (BMG Labtech) at 450nm.  173 \n 174 \nLuminex 175 \nCirculating inflammatory cytokines were quantified using custom 13 -plex Discovery Luminex 176 \n(Bio-Techne, United States) to detect CD163, IL-1b, IL-8/CXCL8, IL-23, MIF , TGF-α, b-NGF , IL-1α, 177 \nIL-6, IL-17A, IL-33, NRG1, and TNF -α according to manufacturer’s instructions. Serum samples 178 \nwere diluted 1:2 , and peritoneal fluid diluted 1:10. All samples were assayed in duplicate. 179 \nLuminex detection was completed using a Luminex xMAP INTELLIFLEX analyser using LX200 low 180 \nsensitivity setting. 181 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\n 182 \nPGE2 ELISA 183 \nFor measurement of p rostaglandin E2 levels  serum and peritoneal fluid were diluted 1:2 and 184 \nassayed in duplicate  according to manufacturer’s instructions ( 500141, Cayman Chemical , 185 \nUnited States). Absorbance was read using Clariostar plate reader (BMG Labtech) at 420nm.  186 \n 187 \nCD14 ELISA 188 \nSerum and peritoneal fluid samples were diluted 1:2 and assayed in duplicated according to 189 \nmanufacturer’s instruction ( A75809, antibodies.com, United Kingdom). Absorbance was read 190 \nusing Clariostar plate reader (BMG Labtech) at 450nm.  191 \n 192 \nCCL18 ELISA 193 \nSerum and peritoneal fluid samples were diluted 1:100 and assayed in duplicate according to 194 \nmanufacturer’s instruction (DCL180B, R&D Systems, United States). Absorbance was read using 195 \nClariostar plate reader (BMG Labtech) at 450nm.  196 \n 197 \nStatistical analysis  198 \nAnalyses were completed in GraphPad Prism 10. ELISA results were interpolated from standard 199 \ncurve generated from each assay’s unique standards and corresponding blank corrected 200 \nabsorbance values.  Luminex analyses were completed using Quantist software (BioTechne , 201 \nUnited States ). Data were assessed for normality using Shapiro -Wilk normality test  and the 202 \nappropriate statistical test chosen accordingly. Linear regression modelling was performed using 203 \nRStudio (Version 2024.12.1+563) using lm() function within the ‘stats’ package including a two-204 \nway interaction term to assess the relationship between endometriosis subtypes and hormone 205 \nuse, with age as a covariate . Comparisons of two groups used Welch’s t -test for normal 206 \ndistribution, or Mann Whitney U test for non -normally distributed data. Comparison of three 207 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\ngroups utilised one -way ANOVA with Tukey’s post-hoc test for normal distribution, or Kruskal -208 \nWallis with Dunn’s post-hoc test for non-normal distribution. 209 \n 210 \nResults 211 \nWomen with superficial endometriosis have lower EFI and serum AMH levels compared to 212 \nwomen without endometriosis 213 \nDemographic information including age  and BMI  of participants  and their use of hormone 214 \ntreatments are summarised in Tables 1 and 2. There was no di@erence in age between the no 215 \nendometriosis and SPE groups, but the SPE+OE women were older than both no endometriosis 216 \nand SPE women (Table 2, Figure 1A). Body mass index (BMI) was comparable between all groups 217 \n(Table 2, Figure 1B).  Most women had no history of being diagnosed with infertility and 43-60% of 218 \nwomen in each group had been pregnant in the past (Table 2). Women with SPE had lower EFI 219 \nscores than women with no endometriosis (Table 3, Figure 1C), while SPE+OE women had lower 220 \nEFI scores compared to both women with no endometriosis, and those with SPE alone (Figure 221 \n1C). Serum AMH levels for SPE+OE were lower than no endometriosis women (Table 3), however 222 \nlinear regression modelling was performed to allow AMH levels between groups to be compared 223 \nwhile accounting for confounding variables like age  and use of hormone treatments  (Table 4). 224 \nBoth SPE and SPE+O E groups had significantly lower AMH levels compared to the no 225 \nendometriosis control when controlling for participant age (p =0.009 and p=0.002, respectively; 226 \nTable 4). When accounting for both age and hormone use, SPE+OE women had significantly lower 227 \nAMH levels (p=0.02), whil e women with SPE alone did not (p=0.069) , suggesting hormone use 228 \nmay contribute to di@erences observed in AMH.  229 \n 230 \nElevated inflammatory cytokines observed in circulation of women with SPE 231 \nWe next sought to understand potential driving mechanisms of this change in AMH with SPE and 232 \nturned to inflammation as a hallmark of endometriosis. Inflammatory cytokines and proteins 233 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nwere quantified using multiplex Luminex and ELISA’s on the same serum samples used to 234 \nmeasure AMH and are summarised in Table 5. When cohorts were separated by use of hormones 235 \nfor the majority of cytokines in serum were not significantly changed between SPE and no 236 \nendometriosis groups  (Table 5). The two exceptions were IL-17 (Figure 2A) and TNF-a (Figure 2B) 237 \nboth of which were significantly increased  in women with  SPE not using hormones  (n=9) 238 \ncompared to controls (n=6); notably these di@erences were not significant is women were using  239 \nhormone therapies. 240 \n 241 \nInflammation in the local peritoneal microenvironment diMers from the circulation 242 \nIn a subset of women (n=15), pelvic peritoneal fluid samples from those not using hormones were 243 \nused to assess inflammation levels in the  local pelvic peritoneal microenvironment.  244 \nConcentrations of peritoneal fluid inflammatory markers are summarised in Table 6. Whilst most 245 \nfactors were detected , variation in levels meant most did not reach statistical significance , 246 \nincluding those previously shown to be elevated in serum. Interestingly, one exception was IL-23 247 \nthat was significantly elevated in women with  SPE not using hormones  compared to those 248 \nwithout endometriosis (Figure 2C).  249 \n 250 \nDiscussion 251 \nThe mechanisms underlying endometriosis -associated infertility are poorly understood  and 252 \nrarely characterised by subtype of endometriosis . Here, we demonstrate for the first time that 253 \nserum AMH is decreased in women who only have lesions identified as  the SPE subtype, 254 \ncompared to women confirmed to have no endometriosis  lesions detected during surgery . 255 \nInterestingly, this finding was associated with elevated pro -inflammatory cytokine levels in the 256 \nsame biospecimens, suggesting inflammation is one mechanism contributing to endometriosis-257 \nassociated delays in conception in women with SPE.  258 \n 259 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nNotably, in our cohort, we found the EFI was lower for women with SPE or SPE+OE compared to 260 \nno endometriosis controls, suggesting a lower probability of future pregnancy success for women 261 \nwith either subtype of endometriosis even though some had already achieved a pregnancy.  Since 262 \nits inception, the EFI has been validated extensively and can be reliably and routinely calculated 263 \nto predict pregnancy success for non -ART conceptions (Adamson and Pasta 2010, Tomassetti, 264 \nGeysenbergh et al. 2013, Vesali, Razavi et al. 2020). However, until our study, it had not been used 265 \nspecifically to evaluate future fertility in women with endometriosis by making a direct 266 \ncomparison to a similar cohort of women without endometriosis. The fact the EFI was reduced in 267 \nour cohort of  women with SPE is  supported by a recent population study  from Finland 268 \ndemonstrating women with endometriosis have a lower overall fertility rate compared to women 269 \nwithout endometriosis (Tuominen, Saavalainen et al. 2025). Notably, in their data was a historical 270 \npopulation-based cohort study (1998 -2012) with data from 18,320 fertile -aged women with a 271 \nsurgical diagnosis of endometriosis; 5786 of whom had a diagnosis of SPE alone. They reported 272 \nlower fertility rates in the endometriosis group compared to a reference group . A lthough, 273 \nconsistent with our data, 68% did achieve a pregnancy during follow up. While registry studies 274 \nprovide large datasets, they are not able to provide insight on whether their lower fertility rate is 275 \ndue to a n underlying  biological reason or less sexual activity due to debilitating symptoms 276 \nassociated with endometriosis. Our study starts to bridge this gap by providing evidence of lower 277 \nEFI and serum AMH in the same  women with SPE alone, or SPE with O E compared to no 278 \nendometriosis controls.  279 \n 280 \nIn this study, we focused on SPE as this is the most common subtype of endometriosis and one 281 \nthat receives less attention in fertility studies than ovarian disease. We also focus on the impact 282 \nto ovarian function and fertility, rather than the endometrium as this has already been the subject 283 \nof several previous studies (reviewed (Gri@iths, Horne et al. 2024). A strength of our cohort is the 284 \nprecise phenotyping of the participants and their disease subtypes . P revious studies have 285 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nassessed fertility in groups of women with endometriosis, irrespective of the subtype  (reviewed 286 \n(Gri@iths, Horne et al. 2024). Our cohort was stratified into groups based on their surgical findings 287 \nand medical history to confirm the absence of any previous diagnosis of an endometrioma that 288 \ncould confound the AMH results. Moreover, the control ‘no endo’ population has advantages over 289 \npreviously reported studies as women  in this group were confirmed as having  no observable 290 \nendometriosis lesions after undergoing an identical diagnostic laparoscopy to those confirmed 291 \nto have endometriosis lesions . In contrast, p revious studies investigating endometriosis -292 \nassociated infertility have either utilised age -matched controls  where the presence of 293 \nasymptomatic and undiagnosed endometriosis has not been  ruled out  surgically, or women  294 \nattending fertility clinics  (Lessans, Gilan et al. 2023) . In both cases there are  likely to be  other 295 \nfactors contributing to infertility, and as such neither is an ideal control  (‘fertile’) group to  296 \ncompare to the fertility in a group of women with endometriosis.  This concern is also based on 297 \nreports describing  that almost half  of women presenting to fertility clinics with unexplained 298 \ninfertility are subsequently found to have endometriosis , most of which have SPE (Van Gestel, 299 \nBafort et al. 2024). 300 \n 301 \nInterestingly, changes in AMH levels were influenced by hormone use and a significant reduction 302 \nin AMH levels for women with SPE  was not seen when hormone use was taken into account  in 303 \nlinear regression modelling. The ability of hormone treatments to alter AMH has been reported 304 \npreviously (Bernardi, Weiss et al. 2021, Hariton, Shirazi et al. 2021, Nelson, Ewing et al. 2023) , 305 \nhowever, the influence of hormone use on AMH levels for women who also have endometriosis 306 \nhas never been investigated to the best of our knowledge. It is possible the lack of change here is 307 \nalso driven by a smaller sample size once part icipants are stratified by their use of hormones.  308 \nTherefore, studies in a larger sample size are warranted to confirm and validate these findings.  309 \n 310 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nTo investigate a potential mechanism by which the pelvic microenvironment may contribute to 311 \ndepleted AMH, the associated inflammatory environment in the peritoneal fluid recovered at the 312 \ntime of surgery from  the same women was characterised.  From the panel of cytokines 313 \ninvestigated here, which were selected based on previous works and evidence in the literature , 314 \nonly IL-17 and TNF-a, and IL-23 were found to be elevated with SPE in the serum and peritoneal 315 \nfluid, respectively. These results align with previous works demonstrating a dysregulated IL-17/IL-316 \n23 axis, and elevated TNF -a levels with endometriosis (Harada, Yoshioka et al. 1997, Sisnett, 317 \nZutautas et al. 2024) . For example, Sisnett et al. (2024) showed elevated IL -23 in the plasma of 318 \npatients with endometriosis (n=13) compared to healthy, fertile controls (n=19) (Sisnett, Zutautas 319 \net al. 2024) . Elevated levels of TNF-a (Harada, Yoshioka et al. 1997)  and IL-17 (Zhang, Xu et al. 320 \n2005) in the peritoneal fluid of women with  endometriosis has been previously reported . A 321 \nstrength of our study over previous work is our subgroup analysis focussed on SPE or SPE+OMA, 322 \nrather than a general endometriosis versus control comparison. Interestingly, Zhang et al. (2005) 323 \nalso reported an even greater increase in IL -17 levels for patients with endometriosis and a 324 \ndiagnosis of infertility compared to endometriosis alone  (Zhang, Xu et al. 2005) . Due to limited 325 \nsample size, we were unable to complete the same analyses. Taken together with our study 326 \nshowing IL-17 is elevated in the same biospecimens where AMH and EFI are reduced, it would be 327 \ninteresting for future studies to attempt to disentangle th e relationship between IL -17 and 328 \nendometriosis pathogenesis and endometriosis-associated infertility.  329 \n 330 \nInterestingly,  di@erences in circulating IL-17 and TNF-a were unique to the participants not using 331 \nhormone treatments . Interestingly, this appeared to be due to a  similar elevation in these 332 \ncytokines in the no endometriosis grou p using hormone treatments. While enhanced 333 \ninflammatory responses to acute stressors have been reported previously in women using 334 \nhormone treatments (Larsen, Cox et al. 2020, Mengelkoch, Gassen et al. 2024), to the best of our 335 \nknowledge this has not been assessed in women with a more chronic inflammatory profile, as 336 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nwith endometriosis. Moreover, it is unclear what the consequences may be on levels of 337 \nproinflammatory cytokines and subsequently AMH levels for women with SPE or SPE+OE if they 338 \nstop taking hormone treatments to attempt to conceive. These are all relevant avenues for future 339 \nwork characterising how inflammation contributes to endometriosis-associated infertility.  340 \n 341 \nSurprisingly, in our study no di@erences were observed in well-established factors known to play 342 \na role in endometriosis-associated symptoms including PGE2 (Rakhila, Carli et al. 2013) and IL-343 \n8 (Jørgensen, Hill et al. 2017) . This may be due to di@erences in  the biospecimens investigated 344 \nwith the Rakhila (2013) study focused on levels in ectopic lesion tissue. The study from Jørgensen 345 \nand colleagues (2017) measured levels of peritoneal fluid and reported significantly higher levels 346 \nof IL-8 in 56 endometriosis patients compared to 38 without endometriosis attending a fertility 347 \nclinic in biospecimens recovered during the luteal/secretory phase. In our study, we had only 8 348 \nsamples from women not on hormones and the increase detected compared with controls was 349 \nnot statistically significant. 350 \nIL-33 has been studied in endometriosis previously and shown to be  elevated with deep 351 \nendometriosis (Santulli, Borghese et al. 2012, Mbarik, Kaabachi et al. 2015, Miller, Monsanto et 352 \nal. 2017). This may explain why it is unchanged in our study, as patients with deep endometriosis 353 \nwere not investigated. Mbarik et al. (2015) divided their cohort by  the revised American Society 354 \nfor Reproductive Medicine staging and found stage I-II endometriosis (closest equivalent to the 355 \nSPE group in the current study) had similar circulating IL-33 levels compared to control but 356 \nelevated levels for the stage III-IV group in both the serum and peritoneal fluid (Mbarik, Kaabachi 357 \net al. 2015). A limitation to our study is also one of its aforementioned strengths. While our control 358 \ngroup are confirmed to have no endometriosis lesions visualised at the time of laparoscopy, they 359 \nall experience pelvic pain justifying their investigation for suspected endometriosis. It is possible 360 \nalterations in the levels of these cytokines may be driven by inflammatory processes similarly 361 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\ncontributing to pelvic pain which may explain the lack of di@erences observed be tween groups 362 \nhere, particularly for the cytokines previously extensively published in relation to endometriosis.  363 \nIt is also possible these inflammatory peritoneal processes present for those with chronic pelvic 364 \npain contribute to infertility. Serum AMH levels in our ‘no endo’ control group were  lower than 365 \nthose reported in previous literature. The mean value for our ‘no endometriosis’ control group was 366 \n1.15ng/mL (compared to 0.89ng/mL in the SPE group). The previous study by Lessans et al. (2023) 367 \nreported a mean AMH value of 3.0ng/mL for their age -matched control group (2.8ng/mL for 368 \nperitoneal endometriosis), and a study combining all subtypes of endometriosis reported mean 369 \nAMH of 2.30ng/mL for healthy controls (1.99ng/mL for endometriosis) (Lessans, Gilan et al. 2023, 370 \nRamezani Tehrani, Mousavi et al. 2025) . Together, these data may suggest a mechanism where 371 \nthe pelvic microenvironment  (including pelvic inflammation) , irrespective of presence of 372 \nendometriosis lesions contributes to diminished AMH and subfertility. Women with other pelvic 373 \ninflammatory conditions such as C rohn’s disease or inflammatory bowel disease are known to 374 \nimpact fertility if they have a flare up of their condition during attempts to conceive and during 375 \npregnancy itself (Nguyen, Seow et al. 2016, Mahadevan, Robinson et al. 2019, Rosiou and 376 \nSelinger 2023, Torres, Chaparro et al. 2023) . While this requires further investigation in the 377 \nsettings of pelvic pain and endometriosis, the notion of an inflammatory peritoneum 378 \ncompromising fertility is plausible. 379 \n 380 \nConclusion 381 \nHere, for the first time, we demonstrate EFI scores and AMH levels are reduced for women with 382 \nSPE compared to women without endometriosis. These changes  are accompanied by greater 383 \nlevels of IL -17 and TNF -a in the serum,  and IL -23 in the peritoneal fluid.  Interestingly, these 384 \ndi@erences were only observed in women not using hormone treatments.  Our findings provide 385 \nvaluable information for clinicians to utilise when counselling women with endometriosis about 386 \ntheir future fertility, with or without an endometrioma present.  387 \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\n 388 \nAcknowledgements 389 \nThe authors would like to thank the EXPPECT Edinburgh clinical team for study recruitment and 390 \nsample collection,  and specifically Dr Lucy Whitaker for clinical input. Also, thanks to the 391 \nexpertise from the University of Edinburgh SURF Biomolecular & Assay Core, specifically Dr 392 \nKirsten Wilson and Linda Ferguson for Luminex technical assistance.  393 \n 394 \nAuthor’s roles  395 \nStudy design: MJG, DAG, PTKS, AWH. Experimental procedures, statistical analysis: MJG, MB, FC. 396 \nResults interpretation: MJG, DAG, PTKS, CED, AWH. Manuscript writing: MJG, DAG, PTKS, AWH. 397 \nManuscript editing: MJG, MB, FC, DAG, CED, PTKS, AWH.  398 \n 399 \nFunding 400 \nM.J.G secured an internal University of Edinburgh Deanery of Clinical Sciences Funding 401 \nChallenge grant to fund part of this work.  402 \nA.W.H receives grants from the National Institute for Health and  Care Research Health 403 \nTechnology Assessment, Chief Scientist O@ice, Wellbeing of Women, Roche Diagnostics, and  404 \nEuropean Union. 405 \n 406 \nConflict of interest 407 \nP.T. K . S .’s  i n s t i t u t i o n  ( U n i v e r s i t y  o f  E d i n b u r g h )  r e c e i v e s  p a y m e n t  f o r  c o n s u l t a n c y  f o r  G e s y n t a ,  408 \nRathlin, Roche and Gideon Richter. 409 \nA.W.H.’s institution (University of Edinburgh) receives personal fees from Rathlin, Theramex and 410 \nGedeon Richter.  411 \n 412 \n 413 \nAll rights reserved. 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No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nTable 1. Participant hormone treatment use.  \n No endo \n% (n) \nSPE \n% (n) \nSPE+OMA \n% (n) \nCOCP 10.25 (4) 11.63 (5) 4.34 (1) \nPOP 20.50 (8) 16.27 (7) 4.34 (1) \nLNGIUS 12.82 (5) 18.60 (8) 13.04 (3) \nDepo-Provera 10.25 (4) 0.00 (0) 4.34 (1) \nOther 10.25 (4) 6.97 (3) 0.00 (0) \nNo hormones 35.89 (14) 46.51 (20) 73.91 (17) \nNo endo – no endometriosis lesions visualised at laparoscopy, SPE – superficial peritoneal \nendometriosis, SPE+OMA – superficial peritoneal and ovarian endometriosis, COCP – combined \noral contraceptive pill, POP – progesterone only pill, LNGIUS – levonorgestrel intrauterine system, \nother includes norethisterone, patch, Nexplanon implant. \n \nTable 2. Participant demographic information.  \n No endo SPE SPE+OMA \nSample size (n)    \nWhole cohort 39 43 23 \nNo hormones 14 20 17 \nHormones 25 23 6 \nAge Mean±SD 27.65 ± 5.81 27.77 ± 6.14 31.73 ± 6.31*^ \nBMI Mean±SD 25.14 ± 5.29 25.68 ± 5.44 27.43 ± 4.92 \nHistory of infertility (n)    \nYes 4 2 8 \nNo 32 36 11 \nInformation unavailable 3 5 4 \nHistory of pregnancy (n)    \nYes 16 26 10 \nNo 19 14 10 \nInformation unavailable 4 3 3 \nNo endo  – no endometriosis lesions visualised at laparoscopy , SPE – superficial peritoneal \nendometriosis, SPE+OMA – superficial peritoneal and ovarian endometriosis, BMI – body mass \nindex, SD – standard deviation. *p<0.05 vs no endo, **p<0.01 vs no endo, ***p<0.001 vs no endo, \n^p<0.05 vs SPE. \n \n \n  \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nTable 3. Endometriosis fertility index and levels of c irculating AMH . Mean±SD or median \n[IQR]. \n No endo  SPE  SPE+OMA  \nEFI Mean±SD 9.41 ± 0.50 (29) 8.63 ± 1.11 (27) 6.95 ± 1.60 (24) \nAMH (ng/mL)    \nMedian [IQR] (n) 1.15 [0.75, 1.94] (36) 0.89 [0.53, 1.52] (41) 0.73 [0.32, 1.19] (29) \nMean ± SD (n) 1.29 ± 0.80 (36) 1.02 ± 0.66 (41) 0.77 ± 0.52 (29) \nNo endo – no endometriosis lesions visualised at laparoscopy, SPE – superficial peritoneal \nendometriosis, SPE+OMA – superficial peritoneal and ovarian endometriosis , EFI – \nendometriosis fertility index, AMH – anti-Mullerian hormone, SD – standard deviation, IQR – \ninterquartile range. \n \n \nTable 4. Linear regression model of AMH. Relationship between AMH and SPE/SPE+OMA vs \ncontrol, with age or age and hormone use taken into consideration. *p<0.05, **p<0.01.  \nPredictor Estimate Standard \nerror \nt-value p-value Significance \nSPE+age -0.64 0.24 -2.68 0.009 ** \nSPE+OMA+age -0.77 0.25 -3.12 0.002 ** \nSPE+age+hormones 0.57  0.31 1.83 0.069 ns \nSPE+OMA+age+hormones 0.96 0.43 2.21 0.02 * \n  \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nTable 5. Cytokine levels in the circulation of women with and without superficial \nendometriosis.  \nCytokine Hormone \ntreatment No endo (n=17) SPE (n=22) \nbNGF (pg/mL) No hormones 2.67 [2.25, 3.92] 3.87 [3.18, 4.50] \nHormones 2.96 [2.82, 4.42] 3.70 [2.47, 4.16] \nCCL18 (ng/mL) No hormones 588.1 [324.1, 773.9] 641.6 [390.0, 770.3] \nHormones 486.9 [367.6, 557.1] 363.8 [307.0, 570.5] \nCD14 (ng/mL) No hormones 4.07 [3.44, 5.69] 4.14 [3.10, 5.36] \nHormones 3.19 [2.68, 3.45] 3.60 [2.96, 4.96] \nCD163 (ng/mL) No hormones 804.8 [196.7, 942.4] 358.3 [305.4, 963.3] \nHormones 447.8 [208.3, 566.4] 613.1 [313.9, 808.6] \nIL-1a (pg/mL) No hormones 0.0 [0.0, 0.03] 0.0 [0.0, 0.18] \nHormones 0.0 [0.0, 0.0] 0.0 [0.0, 0.12] \nIL-1b (pg/mL) No hormones Undetected Undetected \nHormones Undetected Undetected \nIL-6 (pg/mL) No hormones 0.49 [0.07, 1.73] 0.54 [0.07, 4.16] \nHormones 0.56 [0.13, 1.06] 0.22 [0.09, 1.66] \nIL-8 (pg/mL) No hormones 8.97 [4.60, 29.59] 7.34 [3.53, 13.51] \nHormones 5.00 [3.55, 6.77] 6.30 [1.68, 12.74] \nIL-17 (pg/mL) No hormones 3.84 [3.54, 4.19] 4.45 [4.26, 4.88]* \nHormones 4.55 [4.15, 4.66] 4.19 [4.07, 4.59] \nIL-23 (pg/mL) No hormones Undetected 0.0 [0.0, 15.63] \nHormones 0.0 [0.0, 32.8] 0.0 [0.0, 17.7] \nIL-33 (pg/mL) No hormones 0.67 [0.22, 7.85] 1.23 [0.52, 1.73] \nHormones 0.93 [0.06, 9.40] 0.89 [0.18, 25.14] \nMIF (pg/mL) No hormones 662.9 [0.0, 1561] 0.0 [0.0, 3713] \nHormones 1029 [341.5, 1341] 506.8 [138.9, 1355] \nNRG1 (pg/mL) No hormones 0.0 [0.0, 141.8] Undetected \nHormones 1.58 [0.0, 22.61] 0.0 [0.0, 22.77] \nPGE2 (ng/mL) No hormones 337.3 [187.0, 654.0] 215.1 [74.46, 403.4] \nHormones 893.4 [469.6, 2203] 378.1 [178.6, 707.8] \nTGF-a (pg/mL) No hormones 7.79 [3.48, 17.93] 9.58 [6.42, 16.11] \nHormones 9.99 [8.39, 18.49] 13.88 [9.91, 16.83] \nTNF-a (pg/mL) No hormones 1.99 [1.49, 3.43] 4.28 [3.37, 5.88]* \nHormones 2.83 [2.03, 3.73] 2.95 [2.50, 4.35] \nNo endo – no endometriosis lesions visualised at laparoscopy, SPE – superficial peritoneal \nendometriosis, IQR – interquartile range. Median [IQR], *p<0.05 vs no endo.  \n \n  \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\nTable 6. C ytokine levels in the peritoneal fluid from women with and without superficial \nendometriosis.  \nCytokine Hormone treatment No endo (n=6) SPE (n=8) \nbNGF (pg/mL) No hormones 5.07 [3.47, 7.38] 3.91 [2.12, 8.06] \nCCL18 (ng/mL) No hormones 355.9 [232.2, 621.4] 372.9 [269.7, 683.9] \nCD163 (ng/mL) No hormones 720.0 [505.1, 772.3] 701.4 [647.5, 919.9] \nIL-1a (pg/mL) No hormones 4.08 [1.77, 29.07] 5.98 [4.72, 6.49] \nIL-1b (pg/mL) No hormones 5.52 [2.97, 16.89] 3.86 [1.69, 7.81] \nIL-6 (pg/mL) No hormones 156.2 [16.64, 968.4] 36.06 [15.92, 86.30] \nIL-8 (pg/mL) No hormones 11.03 [7.64, 117.5] 16.54 [7.24, 25.47] \nIL-17 (pg/mL) No hormones 10.98 [3.77, 27.04] 6.92 [4.73, 9.81] \nIL-23 (pg/mL) No hormones 121.3 [46.37, 147.6] 212.4 [184.0, 244.5]* \nIL-33 (pg/mL) No hormones 0.21 [0.00, 1.71] 0.00 [0.00, 0.93] \nMIF (pg/mL) No hormones 11904 [3995, 23856] 14089 [6821, 18922] \nNRG1 (pg/mL) No hormones 0.00 [0.00, 12.39] 0.00 [0.00, 0.00] \nPGE2 (ng/mL) No hormones 141.1 [97.84, 495.2] 119.9 [83.87, 324.4] \nTGF-a (pg/mL) No hormones 2.17 [0.14, 9.56] 1.70 [1.00, 2.46] \nTNF-a (pg/mL) No hormones 3.16 [0.74, 6.43] 1.58 [1.08, 3.28] \nNo endo – no endometriosis lesions visualised at laparoscopy, SPE – superficial peritoneal \nendometriosis IQR – interquartile range. Median [IQR], *p<0.05 vs no endo.  \n \n  \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\n \nFigure 1. Women with SPE have impaired fertility. A) SPE+OE women are older than no endo \ncontrols and those with SPE only  (n=26-36), with BMI similar across groups (B ; n=22 -43). \nEndometriosis Fertility Index (EFI) is reduced for both SPE alone and SPE+OMA groups (C ; \nn=24-29). Data are mean±SD, *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. Shapiro-Wilk test \nfor normality, one -way ANOVA with Tukey’s post -hoc test (A) or Kruska l-Wallis with Dunn’s \npost-hoc test (B, C,). \n \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint \n\n \nFigure 2. Women with SPE have elevated inflammatory cytokines, seen only in women not \nusing hormone treatments. Levels of IL17 (A) and TNFa (B) in the circulation, and IL23 (C) in \nthe peritoneal fluid are elevated in women with SPE not using hormones, compared to no endo. \nData are mean±SD, n=6-13/group, *p<0.05, **p<0.01. Shapiro-Wilk test for normality, one-way \nANOVA with Tukey’s post-hoc test (A, B), or Welch’s t-test (C) for significance. \n \n \n \nAll rights reserved. No reuse allowed without permission. \nperpetuity. \npreprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in \nThe copyright holder for thisthis version posted August 27, 2025. ; https://doi.org/10.1101/2025.08.25.25334349doi: medRxiv preprint","source_license":"CC0","license_restricted":false}