Oral Contraceptive Use and Intraocular Pressure: Findings from a Population-Based Cross-Sectional Study

Oral Contraceptive Use and Intraocular Pressure: Findings from a Population-Based Cross-Sectional Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Oral Contraceptive Use and Intraocular Pressure: Findings from a Population-Based Cross-Sectional Study Rozhin Kasiri, Zahra Rahimi, Farideh Moramezi, Elham Zanganeh Yousefabadi, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6674113/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 06 Oct, 2025 Read the published version in BMC Ophthalmology → Version 1 posted 10 You are reading this latest preprint version Abstract Purpose Oral contraceptive pills (OCP) contain hormones that may affect various physiological parameters, including intraocular pressure (IOP). The primary goal of this study was to examine the relationship between OCP use and IOP in women in southwestern Iran. Additionally, we sought to explore associations between IOP, body mass index (BMI), hypertension, and cigarette smoking within this population. Methods This population-based cross-sectional study was conducted as part of the baseline of the Adult and Eye Hoveyzeh cohort study in women aged 35–50 in southwest Iran between 2016 and 2021. Information on socioeconomic factors, demographic characteristics, comorbidities, and family history of glaucoma was collected. Analysis of Covariance was used to compare means between groups while controlling for the effects of covariates. Results Of the 746 participants, 656 (87.9%) were oral contraceptive pill users. An independent t -test found no significant difference in IOP between OCP users ( M = 12.45, SD = 2.13) and non-users ( M = 12.38, SD = 2.11), t (723) = 0.289, p = .773. Additionally, no significant correlation was found between the duration of OCP use and IOP ( r = -0.04, p = .348). An ANCOVA adjusting for age, hypertension, family history of glaucoma, and BMI confirmed that OCP use had no significant effect on IOP ( F (1, 721) = 0.060, p = .806, partial η² < 0.001). These findings suggest that OCP use does not influence IOP. Conclusion This study found no significant association between OCP and IOP, but highlights the importance of healthcare providers and patients being aware of potential glaucoma risks and monitoring any changes in IOP. Oral Contraceptive Pills Intraocular Pressure Adult Iran Figures Figure 1 Figure 2 Introduction Oral contraceptive pills (OCPs) are a form of hormonal contraception designed to prevent pregnancy ( 1 ) and have been widely used since their introduction in the 1960s ( 2 ). They are available in two main types: Combined Oral Contraceptives (COCs) and Progestogen-Only Pills (POPs) ( 3 ). OCPs offer numerous benefits beyond pregnancy prevention. They help regulate menstrual cycles, reduce menstrual cramps and heavy bleeding, and can improve conditions like acne and hirsutism, particularly in women with polycystic ovary syndrome (PCOS). Long-term use of OCPs significantly reduces the risk of ovarian and endometrial cancers, and may also lower the risk of pelvic inflammatory disease (PID) and ectopic pregnancies ( 4 ). Additionally, they can alleviate symptoms of endometriosis and premenstrual syndrome (PMS) ( 5 ). OCPs are convenient to use, do not interfere with sexual activity, and allow for quick return of fertility when discontinued. Overall, they provide a range of health benefits that can improve the quality of life for many women. Oral contraceptives can cause a range of side effects, from mild to serious. Common side effects include spotting or breakthrough bleeding, nausea, headaches, breast tenderness, mood changes, weight fluctuations, bloating, fatigue, and dizziness. Some users may experience acne, which can either improve or worsen. More serious risks involve increased chances of blood clots, stroke, and heart attack, particularly with certain types of pills ( 6 ). There is also a slight increase in high blood pressure and some cancers, such as breast and cervical cancer, though they reduce the risk of ovarian and endometrial cancer ( 7 ). Intraocular pressure (IOP) refers to the fluid pressure inside the eye, specifically within the aqueous humor, which is the clear liquid between the cornea and the lens. This pressure is crucial for maintaining the eye's shape and function ( 8 ). IOP is regulated by the balance between the production and drainage of aqueous humor through the trabecular meshwork and uveoscleral outflow ( 9 ). Normal IOP ranges from 10 to 21 millimeters of mercury (mmHg), with an average of about 15.5 mmHg ( 10 ). Elevated IOP, known as ocular hypertension, can lead to conditions like glaucoma if not treated, potentially causing optic nerve damage and vision loss ( 11 ). The eyes have receptors for sex hormones found in various parts of the eye, such as the glands and conjunctiva. These receptors respond to androgens, estrogens, and progestins and can be affected by hormonal contraceptives ( 12 ). OCPs have been associated with changes in IOP. Studies indicate that OCPs can increase IOP, even with short-term use, which may pose a risk for conditions like glaucoma, a leading cause of blindness ( 13 , 14 ). The exact mechanism behind this increase is not fully understood, but it is thought to relate to hormonal changes caused by OCPs ( 15 ). Long-term use, particularly for three years or more, has been linked to a higher risk of developing glaucoma ( 16 ). However, estrogen is generally known to decrease IOP, suggesting that the progestin component in OCPs might be responsible for the observed effects ( 17 ). These controversies prompted this study aimed at investigating the effect of oral contraceptive pills on intraocular pressure in women of childbearing age. Methodology Study Design and Participants This cross-sectional, population-based study involved women aged 35–70 who participated in the Hoveyzeh Cohort Study (HCS), a subset of the Prospective Epidemiological Research Studies in Iran [PERSIAN] ( 18 , 19 ). The HCS, conducted in southwest Iran, initially enrolled 10,009 adults from May 2016. For this analysis, from the 5,983 women aged 35–70 years in HCS, we applied exclusion criteria including menopause status, use of hormonal contraceptives other than for this study, smoking, alcohol consumption, history of cardiovascular disease, diabetes, renal failure, and age ≥ 50 years, resulting in a final sample of 2,272 women. Data collection protocols, including questionnaires and biological sampling, were meticulously implemented following rigorous Quality Assurance (QA) and Quality Control (QC) procedures at multiple levels, ensuring data integrity throughout all study phases that were previously published ( 18 , 19 ). Oral contraceptive pills The use of OCP includes cyclophosphamide, LD, HD, medroxyprogesterone acetate, etc. ( 20 ). Eye examination procedures Participants were enrolled in the study between 7:30 a.m. and 9:00 a.m. Each participant first completed a structured optometry questionnaire capturing demographic data and relevant medical history, including age, history of diabetes, prior eye surgeries, and family history of glaucoma. Following this, a comprehensive eye examination was performed. Intraocular pressure The eyes were examined for corneal opacities and eyelid lesions such as ptosis, entropion, ectropion, using a slit lamp. A local anesthetic drop was instilled into the inferior conjunctival sac, followed by staining of the cornea with a dry fluorescein strip. IOP was then measured using a Goldmann tonometer, and the results were reported in millimeters of mercury (mmHg). The right eye was evaluated first, and if the estimated IOP was greater than 20 mmHg, the measurement was repeated ( 19 ). IOP refers to the fluid pressure inside the eye, primarily maintained by the balance between the production and drainage of aqueous humor, a watery fluid found in the front part of the eye. It plays a crucial role in maintaining the shape of the eye and ensuring proper visual function( 21 ). Definition of covariates Body mass index (BMI) was calculated as weight (kg) divided by squared height (m2) (< 18.5 = Underweight, 18.5–24.9 = Normal, 25.0- 29.9 = Overweight, and ≥ 30 = Obese). We used the International Physical Activity Questionnaire (IPAQ) to assess the physical activity levels among the participants based on the Metabolic Equivalent of task (MET). A daily physical activity questionnaire was used to measure METs of activity for all participants over a 24-hour day, and quartiles were calculated for all participants ( 22 ). Each participant’s MET score was classified into four quartiles (Q1 to Q4) based on the quartile classification. We also considered education levels (Illiterate, Primary school, Secondary school, High school Diploma, and University), residence type (Urban and Rural), and age groups (35–39, 40–44, and 45–49). Additionally, we recorded the place of residence as urban or rural (and defined a smoker as an individual who has consumed at least 100 cigarettes throughout their lifetime (Yes, No). Furthermore, the wealth index utilized in this study serves as a household's assets. This index is calculated by considering various factors, such as the ownership of assets like televisions, bicycles, cars, and computers, among others. The calculated wealth scores were then transformed into five quintiles, ranging from the poorest to the richest categories. Family history of glaucoma (Yes, No), hypertension (yes/no), blood pressure > 140/90, the use of blood pressure-lowering medications, or self-reported diagnosis of hypertension. Statistical analysis The mean and standard deviation (SD) were used to describe continuous variables, while the number and percent were used for categorical variables. The relationship between categorical variables was assessed using the chi-square test. The normality hypothesis for continuous variables was tested using the Kolmogorov-Smirnov test. The independent t-test was used to compare continuous variables between the two groups. Analysis of covariance (ANCOVA) was utilized to correct for comparisons between groups by statistically controlling for covariates. The analyses were conducted using Stata version 14. The significance level for all statistical tests was set at less than 0.05. Results A total of 746 individuals were evaluated in this analysis. The mean age of the participants was 41.73 ± 3.98. Of the participants, 656 (87.9%) were oral contraceptive pill users and 90 (12.1%) were non-users of OCPs. The mean duration of oral contraceptive pill use was 78.82 ± 62.50 years. Findings showed a significant use of OCP among women aged 35–44 years (83.5%) and 45–50 years (100%). The usage of OCP was higher among less educated women, particularly significant at the primary school level (85.0%, p = 0.001). There was no significant relationship between wealth index and OCP usage (p = 0.429), indicating similar usage rates across different economic categories. Additionally, there was no significant difference in OCP usage between smokers and non-smokers (p = 0.385), or based on urban (88.5%) vs. rural (86.7%) residence (p = 0.480). There was a significant correlation between OCP use and physical activity, particularly in Q3 (91.1%, p = 0.011), suggesting that more physically active women were more likely to use OCPs. However, there was no significant relationship between BMI categories and OCP usage (p = 0.118), although underweight women had high usage rates. Women with hypertension had a significant association with OCP use (p = 0.03); with higher usage rates (94.0%) (Table 1 ). Table 1 Demographic, and comorbidity characteristics of the participants Variable Oral contraceptive pill user p-value Yes n(%) No n(%) Age category 35–44 years 454 (83.5) 90 (16.5) < 0.001 45–50 years 202 (100) 0 (0.0) Education levels Illiteracy 434 (91.2) 42(8.8) Primary school 136(85.0) 24(15.0) 0.001 Secondary school 34(77.3) 10(22.7) High school and Diploma 31(86.1) 5(13.9) University 21(70.0) 9(30.0) Wealth score Poorest 109(83.8) 21(16.2) Poor 145(90.6) 15(9.4) 0.429 Moderate 128(88.5) 20(13.5) Rich 129(88.4) 17(11.6) Richest 145(89.5) 17(10.5) Smoking Non-smoker 643(87.7) 90 (12.3) Smoker 13(100.0) 0(0.0) 0.385 Residence Type Urban 440(88.5) 57(11.5) 0.480 Rural 216(86.7) 33(13.3) Physical activity (MET) Q1 54(84.4) 10(15.6) Q2 171(82.2) 37(17.8) Q3 257(91.1) 25(8.9) 0.011 Q4 174(90.6) 18(9.4) Body mass index Underweight 8(100.0) 0(0.0) Normal 104(83.9) 20(16.1) 0.118 Overweight 231(86.2) 37(13.8) Obese 313(90.5) 33(9.5) Hypertension No 547(86.8) 83(13.2) 0.03 Yes 109(94.0) 7(6.0) An independent samples t-test was conducted to compare IOP between users and non-users of oral contraceptive pills. The results revealed that users of oral contraceptive pills (M = 12.45, SD = 2.13) did not have significantly higher IOP than non-users (M = 12.38, SD = 2.11), t (723) = 0.289, p = 0.773. (Fig. 2 ) In the correlation analysis, it was found that there was no statistically significant relationship between the duration of contraceptive pill use and the mean intraocular pressure (n = 725, r = -0.04, p = 0.348). ANCOVA was used to assess the impact of oral contraceptive use on intraocular pressure, while adjusting for covariates such as age, hypertension, family history of glaucoma, and BMI. The low F-value of 0.060 indicates a minimal effect of OCP use on IOP. Additionally, the P-value of 0.806 shows that this effect is not statistically significant (typically, p < 0.05 is considered significant). The partial Eta-squared value of < 0.001 indicates that when controlling for covariates, the effect size of OCP use on IOP is negligible (Table 2 ). Table 2 ANCOVA results for the effect of oral contraceptive pill use on the intraocular pressure after control covariates Variable Mean(SE) F (1,719) P-value Partial eta-squared Use contraceptive 0.060 0.806 < 0.001 No 12.469(0.230) Yes 12.433 (0.084) * Adjusted for age, hypertension, family history of Glaucoma, and body mass index Discussion The study aimed to explore the link between oral contraceptive use and intraocular pressure in women from southwestern Iran. It involved 746 participants, with 87.9% using oral contraceptives. The highest usage was among women aged 35–50 and less educated individuals. No significant differences were found in usage based on wealth, smoking status, or residence. The study found a not statistically significant effect of contraceptive use on intraocular pressure. Hormone therapy is extensively utilized for numerous reasons, including birth control ( 23 , 24 ). Our findings indicated that the average intraocular pressure was elevated among users of contraceptive methods, which may have clinical significance. However, these findings did not reach statistical significance. Our results do not align with some previous studies indicating that the use of hormonal contraceptives is linked to elevated IOP. For example, some studies have indicated that long-term use of OCPs (three years or more) is linked to elevated IOP and a higher risk of developing glaucoma, including primary open-angle glaucoma (POAG) ( 15 – 17 ). Additionally, a cohort study within the Nurses' Health Study ( 25 ) revealed that a five-year duration of oral contraceptive use was associated with a 25% increased risk of POAG. However, the results of other studies, such as one that ( 26 ) showed a decrease in IOP with oral contraceptive use, align with our findings. The study`s findings may be justified by several points, including controversies with our study. One explanation is differences in demographic characteristics, particularly age. The participants in our study were relatively young, with an average age of about 41 years. Previous research has indicated that there is no significant change in IOP among younger women who use OCP, but there is a significant increase in older women ( 27 ). The second explanation is supported by the fact that postmenopausal women, who experience a decrease in circulating estrogen levels, have a higher incidence of glaucoma and an increase in IOP compared to premenopausal women of the same age ( 28 ). However, menopausal women were excluded from our study. The third explanation is based on a study comparing contraceptive methods, which found that women using oral contraceptives (including progestin-only formulations), had a mean IOP of 15.2 mmHg, significantly higher than those using injectable contraceptives or implants. Although the study did not specifically isolate progestin-only pills, it suggests a trend towards elevated IOP in oral contraceptive users ( 29 ). Estrogen, a component of COCs, typically reduces IOP by protecting retinal ganglion cells and improving outflow, but its combination with progestin in COCs may have paradoxical effects over time ( 17 , 30 ). Conclusion Although our study did not find a statistically significant association between mean intraocular pressure and oral contraceptive use, the exact relationship between these hormones and the risk of glaucoma needs further investigation. Physicians prescribing OCPs and patients taking them should be informed about the potential risk of glaucoma. Any slight change in IOP should be reported to help determine if there is a connection between OCP use and the risk of glaucoma. Finally, it is recommended that a future study be conducted to compare the impact of various contraceptive methods on women's eye health. Declarations Ethics statement The ethics committee approved the study protocol of Ahvaz Jundishapur University of Medical Sciences (IR.AJUMS.REC.1403.304). This study was conducted based on the Helsinki Declaration and its later amendments. On the registration day, informed written consent was obtained from the study participants. Data availability Data will be available on request from the corresponding author. Author contributions AK, RK contributed to the design and preparation of the manuscript and its interpretation. ZR was involved in the data collection, performed the statistical analysis, and was a major contributor to the writing of the manuscript. FM and EZY interpreted the research data. .A.M, and M.A.K: Collected data and wrote the paper. All authors read and approved the final manuscript. Funding This research was funded by the Vice-Chancellor for Research at Ahvaz Jundishapur University of Medical Sciences, grant number HCS-0306. As our funding body played no role in the study design and data gathering, analysis, and interpretation of data and the writing of the manuscript. Acknowledgments We would like to thank the participants and staff of the Hoveyzeh Cohort Study Center who assisted us in conducting this study. Conflict of interest The authors declare no competing interests. References Cameron NA, Blyler CA, Bello NA. Oral contraceptive pills and hypertension: a review of current evidence and recommendations. Hypertension. 2023;80(5):924-35. Gandhi AB, Supe PA. Evolution of Oral Contraceptive Pills. The Journal of Obstetrics and Gynecology of India. 2024;74(2):109-12. Römer T, Bitzer J, Egarter C, Hadji P, Kiechle M, Kramer H, et al. Oral progestins in hormonal contraception: importance and future perspectives of a new progestin only-pill containing 4 mg drospirenone. Geburtshilfe und Frauenheilkunde. 2021;81(09):1021-30. Samanta M, Maiti M. Effects of oral contraceptive pill on female health. 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Cite Share Download PDF Status: Published Journal Publication published 06 Oct, 2025 Read the published version in BMC Ophthalmology → Version 1 posted Editorial decision: Revision requested 26 Jun, 2025 Reviews received at journal 20 Jun, 2025 Reviews received at journal 17 Jun, 2025 Reviewers agreed at journal 16 Jun, 2025 Reviewers agreed at journal 15 Jun, 2025 Reviewers invited by journal 01 Jun, 2025 Editor assigned by journal 01 Jun, 2025 Editor invited by journal 28 May, 2025 Submission checks completed at journal 28 May, 2025 First submitted to journal 28 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6674113","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":465075321,"identity":"c9e9bf7a-edbe-4568-9035-a38e87de75dc","order_by":0,"name":"Rozhin 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15:38:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6674113/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6674113/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12886-025-04413-0","type":"published","date":"2025-10-06T15:57:37+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":83905477,"identity":"f994b856-377b-47ee-ad37-05bfc9109836","added_by":"auto","created_at":"2025-06-04 10:14:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":36505,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the participants in this study\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6674113/v1/e219fd17284fde0f65cbf2e4.png"},{"id":83905478,"identity":"9f749886-fc3e-4582-af76-7f6a6594163b","added_by":"auto","created_at":"2025-06-04 10:14:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":28376,"visible":true,"origin":"","legend":"\u003cp\u003eThe comparison of mean (SD) of intraocular pressure in the participants by oral contraceptive pills\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6674113/v1/db7d129be54f80566aad3153.png"},{"id":93419817,"identity":"3c2fbf53-5fe2-4a64-8f04-613d83d3672a","added_by":"auto","created_at":"2025-10-13 16:08:00","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":716408,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6674113/v1/cc40564c-db07-4d1d-82fb-f03915d89b51.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Oral Contraceptive Use and Intraocular Pressure: Findings from a Population-Based Cross-Sectional Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eOral contraceptive pills (OCPs) are a form of hormonal contraception designed to prevent pregnancy (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) and have been widely used since their introduction in the 1960s (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). They are available in two main types: Combined Oral Contraceptives (COCs) and Progestogen-Only Pills (POPs) (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). OCPs offer numerous benefits beyond pregnancy prevention. They help regulate menstrual cycles, reduce menstrual cramps and heavy bleeding, and can improve conditions like acne and hirsutism, particularly in women with polycystic ovary syndrome (PCOS). Long-term use of OCPs significantly reduces the risk of ovarian and endometrial cancers, and may also lower the risk of pelvic inflammatory disease (PID) and ectopic pregnancies (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Additionally, they can alleviate symptoms of endometriosis and premenstrual syndrome (PMS) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). OCPs are convenient to use, do not interfere with sexual activity, and allow for quick return of fertility when discontinued. Overall, they provide a range of health benefits that can improve the quality of life for many women. Oral contraceptives can cause a range of side effects, from mild to serious. Common side effects include spotting or breakthrough bleeding, nausea, headaches, breast tenderness, mood changes, weight fluctuations, bloating, fatigue, and dizziness. Some users may experience acne, which can either improve or worsen. More serious risks involve increased chances of blood clots, stroke, and heart attack, particularly with certain types of pills (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). There is also a slight increase in high blood pressure and some cancers, such as breast and cervical cancer, though they reduce the risk of ovarian and endometrial cancer (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIntraocular pressure (IOP) refers to the fluid pressure inside the eye, specifically within the aqueous humor, which is the clear liquid between the cornea and the lens. This pressure is crucial for maintaining the eye's shape and function (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). IOP is regulated by the balance between the production and drainage of aqueous humor through the trabecular meshwork and uveoscleral outflow (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Normal IOP ranges from 10 to 21 millimeters of mercury (mmHg), with an average of about 15.5 mmHg (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Elevated IOP, known as ocular hypertension, can lead to conditions like glaucoma if not treated, potentially causing optic nerve damage and vision loss (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe eyes have receptors for sex hormones found in various parts of the eye, such as the glands and conjunctiva. These receptors respond to androgens, estrogens, and progestins and can be affected by hormonal contraceptives (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). OCPs have been associated with changes in IOP. Studies indicate that OCPs can increase IOP, even with short-term use, which may pose a risk for conditions like glaucoma, a leading cause of blindness (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). The exact mechanism behind this increase is not fully understood, but it is thought to relate to hormonal changes caused by OCPs (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Long-term use, particularly for three years or more, has been linked to a higher risk of developing glaucoma (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). However, estrogen is generally known to decrease IOP, suggesting that the progestin component in OCPs might be responsible for the observed effects (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). These controversies prompted this study aimed at investigating the effect of oral contraceptive pills on intraocular pressure in women of childbearing age.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003eStudy Design and Participants\u003c/p\u003e \u003cp\u003eThis cross-sectional, population-based study involved women aged 35\u0026ndash;70 who participated in the Hoveyzeh Cohort Study (HCS), a subset of the Prospective Epidemiological Research Studies in Iran [PERSIAN] (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e). The HCS, conducted in southwest Iran, initially enrolled 10,009 adults from May 2016. For this analysis, from the 5,983 women aged 35\u0026ndash;70 years in HCS, we applied exclusion criteria including menopause status, use of hormonal contraceptives other than for this study, smoking, alcohol consumption, history of cardiovascular disease, diabetes, renal failure, and age\u0026thinsp;\u0026ge;\u0026thinsp;50 years, resulting in a final sample of 2,272 women. Data collection protocols, including questionnaires and biological sampling, were meticulously implemented following rigorous Quality Assurance (QA) and Quality Control (QC) procedures at multiple levels, ensuring data integrity throughout all study phases that were previously published (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eOral contraceptive pills\u003c/h2\u003e \u003cp\u003eThe use of OCP includes cyclophosphamide, LD, HD, medroxyprogesterone acetate, etc. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eEye examination procedures\u003c/h3\u003e\n\u003cp\u003eParticipants were enrolled in the study between 7:30 a.m. and 9:00 a.m. Each participant first completed a structured optometry questionnaire capturing demographic data and relevant medical history, including age, history of diabetes, prior eye surgeries, and family history of glaucoma. Following this, a comprehensive eye examination was performed.\u003c/p\u003e\n\u003ch3\u003eIntraocular pressure\u003c/h3\u003e\n\u003cp\u003eThe eyes were examined for corneal opacities and eyelid lesions such as ptosis, entropion, ectropion, using a slit lamp. A local anesthetic drop was instilled into the inferior conjunctival sac, followed by staining of the cornea with a dry fluorescein strip. IOP was then measured using a Goldmann tonometer, and the results were reported in millimeters of mercury (mmHg). The right eye was evaluated first, and if the estimated IOP was greater than 20 mmHg, the measurement was repeated (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e). IOP refers to the fluid pressure inside the eye, primarily maintained by the balance between the production and drainage of aqueous humor, a watery fluid found in the front part of the eye. It plays a crucial role in maintaining the shape of the eye and ensuring proper visual function(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003eDefinition of covariates\u003c/h3\u003e\n\u003cp\u003eBody mass index (BMI) was calculated as weight (kg) divided by squared height (m2) (\u0026lt;\u0026thinsp;18.5\u0026thinsp;=\u0026thinsp;Underweight, 18.5\u0026ndash;24.9\u0026thinsp;=\u0026thinsp;Normal, 25.0- 29.9\u0026thinsp;=\u0026thinsp;Overweight, and \u0026ge;\u0026thinsp;30\u0026thinsp;=\u0026thinsp;Obese). We used the International Physical Activity Questionnaire (IPAQ) to assess the physical activity levels among the participants based on the Metabolic Equivalent of task (MET). A daily physical activity questionnaire was used to measure METs of activity for all participants over a 24-hour day, and quartiles were calculated for all participants (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). Each participant\u0026rsquo;s MET score was classified into four quartiles (Q1 to Q4) based on the quartile classification. We also considered education levels (Illiterate, Primary school, Secondary school, High school Diploma, and University), residence type (Urban and Rural), and age groups (35\u0026ndash;39, 40\u0026ndash;44, and 45\u0026ndash;49). Additionally, we recorded the place of residence as urban or rural (and defined a smoker as an individual who has consumed at least 100 cigarettes throughout their lifetime (Yes, No). Furthermore, the wealth index utilized in this study serves as a household's assets. This index is calculated by considering various factors, such as the ownership of assets like televisions, bicycles, cars, and computers, among others. The calculated wealth scores were then transformed into five quintiles, ranging from the poorest to the richest categories. Family history of glaucoma (Yes, No), hypertension (yes/no), blood pressure\u0026thinsp;\u0026gt;\u0026thinsp;140/90, the use of blood pressure-lowering medications, or self-reported diagnosis of hypertension.\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThe mean and standard deviation (SD) were used to describe continuous variables, while the number and percent were used for categorical variables. The relationship between categorical variables was assessed using the chi-square test. The normality hypothesis for continuous variables was tested using the Kolmogorov-Smirnov test. The independent t-test was used to compare continuous variables between the two groups. Analysis of covariance (ANCOVA) was utilized to correct for comparisons between groups by statistically controlling for covariates. The analyses were conducted using Stata version 14. The significance level for all statistical tests was set at less than 0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 746 individuals were evaluated in this analysis. The mean age of the participants was 41.73\u0026thinsp;\u0026plusmn;\u0026thinsp;3.98. Of the participants, 656 (87.9%) were oral contraceptive pill users and 90 (12.1%) were non-users of OCPs. The mean duration of oral contraceptive pill use was 78.82\u0026thinsp;\u0026plusmn;\u0026thinsp;62.50 years.\u003c/p\u003e \u003cp\u003eFindings showed a significant use of OCP among women aged 35\u0026ndash;44 years (83.5%) and 45\u0026ndash;50 years (100%). The usage of OCP was higher among less educated women, particularly significant at the primary school level (85.0%, p\u0026thinsp;=\u0026thinsp;0.001). There was no significant relationship between wealth index and OCP usage (p\u0026thinsp;=\u0026thinsp;0.429), indicating similar usage rates across different economic categories. Additionally, there was no significant difference in OCP usage between smokers and non-smokers (p\u0026thinsp;=\u0026thinsp;0.385), or based on urban (88.5%) vs. rural (86.7%) residence (p\u0026thinsp;=\u0026thinsp;0.480). There was a significant correlation between OCP use and physical activity, particularly in Q3 (91.1%, p\u0026thinsp;=\u0026thinsp;0.011), suggesting that more physically active women were more likely to use OCPs. However, there was no significant relationship between BMI categories and OCP usage (p\u0026thinsp;=\u0026thinsp;0.118), although underweight women had high usage rates. Women with hypertension had a significant association with OCP use (p\u0026thinsp;=\u0026thinsp;0.03); with higher usage rates (94.0%) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic, and comorbidity characteristics of the participants\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOral contraceptive pill user\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003cp\u003e\u003cb\u003en(%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003cp\u003e\u003cb\u003en(%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge category\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e35\u0026ndash;44 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e454 (83.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90 (16.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e45\u0026ndash;50 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e202 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eEducation levels\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIlliteracy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e434 (91.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42(8.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary school\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e136(85.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24(15.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSecondary school\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34(77.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(22.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHigh school and Diploma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31(86.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5(13.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUniversity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(70.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9(30.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eWealth score\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePoorest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e109(83.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21(16.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePoor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e145(90.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15(9.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.429\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModerate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e128(88.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(13.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRich\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e129(88.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17(11.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRichest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e145(89.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17(10.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSmoking\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNon-smoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e643(87.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90 (12.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13(100.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.385\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eResidence Type\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrban\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e440(88.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57(11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.480\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRural\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e216(86.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33(13.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePhysical activity (MET)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQ1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54(84.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(15.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQ2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e171(82.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37(17.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQ3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e257(91.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25(8.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.011\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQ4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e174(90.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18(9.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBody mass index\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUnderweight\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8(100.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e104(83.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(16.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.118\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOverweight\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e231(86.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37(13.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObese\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e313(90.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33(9.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHypertension\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e547(86.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e83(13.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e109(94.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7(6.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAn independent samples t-test was conducted to compare IOP between users and non-users of oral contraceptive pills. The results revealed that users of oral contraceptive pills (M\u0026thinsp;=\u0026thinsp;12.45, SD\u0026thinsp;=\u0026thinsp;2.13) did not have significantly higher IOP than non-users (M\u0026thinsp;=\u0026thinsp;12.38, SD\u0026thinsp;=\u0026thinsp;2.11), t (723)\u0026thinsp;=\u0026thinsp;0.289, p\u0026thinsp;=\u0026thinsp;0.773. (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the correlation analysis, it was found that there was no statistically significant relationship between the duration of contraceptive pill use and the mean intraocular pressure (n\u0026thinsp;=\u0026thinsp;725, r = -0.04, p\u0026thinsp;=\u0026thinsp;0.348).\u003c/p\u003e \u003cp\u003eANCOVA was used to assess the impact of oral contraceptive use on intraocular pressure, while adjusting for covariates such as age, hypertension, family history of glaucoma, and BMI. The low F-value of 0.060 indicates a minimal effect of OCP use on IOP. Additionally, the P-value of 0.806 shows that this effect is not statistically significant (typically, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 is considered significant). The partial Eta-squared value of \u0026lt;\u0026thinsp;0.001 indicates that when controlling for covariates, the effect size of OCP use on IOP is negligible (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eANCOVA results for the effect of oral contraceptive pill use on the intraocular pressure after control covariates\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean(SE)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF (1,719)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePartial eta-squared\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eUse contraceptive\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.060\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.806\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e12.469(0.230)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e12.433 (0.084)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003cb\u003e*\u003c/b\u003eAdjusted for age, hypertension, family history of Glaucoma, and body mass index\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe study aimed to explore the link between oral contraceptive use and intraocular pressure in women from southwestern Iran. It involved 746 participants, with 87.9% using oral contraceptives. The highest usage was among women aged 35\u0026ndash;50 and less educated individuals. No significant differences were found in usage based on wealth, smoking status, or residence. The study found a not statistically significant effect of contraceptive use on intraocular pressure.\u003c/p\u003e \u003cp\u003eHormone therapy is extensively utilized for numerous reasons, including birth control (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). Our findings indicated that the average intraocular pressure was elevated among users of contraceptive methods, which may have clinical significance. However, these findings did not reach statistical significance. Our results do not align with some previous studies indicating that the use of hormonal contraceptives is linked to elevated IOP. For example, some studies have indicated that long-term use of OCPs (three years or more) is linked to elevated IOP and a higher risk of developing glaucoma, including primary open-angle glaucoma (POAG) (\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). Additionally, a cohort study within the Nurses' Health Study (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e) revealed that a five-year duration of oral contraceptive use was associated with a 25% increased risk of POAG. However, the results of other studies, such as one that (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e) showed a decrease in IOP with oral contraceptive use, align with our findings.\u003c/p\u003e \u003cp\u003eThe study`s findings may be justified by several points, including controversies with our study. One explanation is differences in demographic characteristics, particularly age. The participants in our study were relatively young, with an average age of about 41 years. Previous research has indicated that there is no significant change in IOP among younger women who use OCP, but there is a significant increase in older women (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe second explanation is supported by the fact that postmenopausal women, who experience a decrease in circulating estrogen levels, have a higher incidence of glaucoma and an increase in IOP compared to premenopausal women of the same age (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e). However, menopausal women were excluded from our study.\u003c/p\u003e \u003cp\u003eThe third explanation is based on a study comparing contraceptive methods, which found that women using oral contraceptives (including progestin-only formulations), had a mean IOP of 15.2 mmHg, significantly higher than those using injectable contraceptives or implants. Although the study did not specifically isolate progestin-only pills, it suggests a trend towards elevated IOP in oral contraceptive users (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e). Estrogen, a component of COCs, typically reduces IOP by protecting retinal ganglion cells and improving outflow, but its combination with progestin in COCs may have paradoxical effects over time (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eAlthough our study did not find a statistically significant association between mean intraocular pressure and oral contraceptive use, the exact relationship between these hormones and the risk of glaucoma needs further investigation. Physicians prescribing OCPs and patients taking them should be informed about the potential risk of glaucoma. Any slight change in IOP should be reported to help determine if there is a connection between OCP use and the risk of glaucoma. Finally,\u0026nbsp;it is recommended that a future study be conducted to compare the\u0026nbsp;impact of various contraceptive methods on women's eye health.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe ethics committee approved the study protocol of Ahvaz Jundishapur University of Medical Sciences (IR.AJUMS.REC.1403.304). This study was conducted based on the Helsinki Declaration and its later amendments. On the registration day, informed written consent was obtained from the study participants.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData will be available on request from the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAK, RK contributed to the design and preparation of the manuscript and its interpretation. ZR was involved in the data collection, performed the statistical analysis, and\u0026nbsp;was a major contributor to the writing of the manuscript. FM and EZY interpreted the research data. .A.M, and M.A.K: Collected data and wrote the paper. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was funded by the Vice-Chancellor for Research at Ahvaz Jundishapur University of Medical Sciences, grant number\u0026nbsp;HCS-0306. As our funding body\u0026nbsp;played no role in the study design and data gathering, analysis, and interpretation of data and the writing of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to thank the participants and staff of the Hoveyzeh Cohort Study Center who assisted us in conducting this study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCameron NA, Blyler CA, Bello NA. Oral contraceptive pills and hypertension: a review of current evidence and recommendations. Hypertension. 2023;80(5):924-35.\u003c/li\u003e\n\u003cli\u003eGandhi AB, Supe PA. Evolution of Oral Contraceptive Pills. The Journal of Obstetrics and Gynecology of India. 2024;74(2):109-12.\u003c/li\u003e\n\u003cli\u003eR\u0026ouml;mer T, Bitzer J, Egarter C, Hadji P, Kiechle M, Kramer H, et al. Oral progestins in hormonal contraception: importance and future perspectives of a new progestin only-pill containing 4 mg drospirenone. Geburtshilfe und Frauenheilkunde. 2021;81(09):1021-30.\u003c/li\u003e\n\u003cli\u003eSamanta M, Maiti M. Effects of oral contraceptive pill on female health. Int J Exp Res Rev. 2022;28:15-24.\u003c/li\u003e\n\u003cli\u003eMontero-Vilchez T, Valenzuela-Amigo A, Cuenca-Barrales C, Arias-Santiago S, Leyva-Garc\u0026iacute;a A, Molina-Leyva A. The role of oral contraceptive pills in hidradenitis suppurativa: a cohort study. Life. 2021;11(7):697.\u003c/li\u003e\n\u003cli\u003eJain A, Dwyer SC, Mozumdar A, Tobey E. Not all women who experience side effects discontinue their contraceptive method: insights from a longitudinal study in India. Studies in Family Planning. 2021;52(2):165-78.\u003c/li\u003e\n\u003cli\u003eJahanfar S, Mortazavi J, Lapidow A, Cu C, Al Abosy J, Morris K, et al. Assessing the impact of contraceptive use on reproductive cancer risk among women of reproductive age\u0026mdash;a systematic review. Frontiers in Global Women\u0026apos;s Health. 2024;5:1487820.\u003c/li\u003e\n\u003cli\u003eMachiele R, Motlagh M, Zeppieri M, Patel BC. Intraocular pressure. StatPearls [Internet]: StatPearls Publishing; 2024.\u003c/li\u003e\n\u003cli\u003eFreddo TF, Civan M, Gong H. Aqueous humor and the dynamics of its flow: mechanisms and routes of aqueous humor drainage. Albert and Jakobiec\u0026apos;s Principles and Practice of Ophthalmology: Springer; 2022. p. 1989-2033.\u003c/li\u003e\n\u003cli\u003eEl Habbak AH, Elsayed M, Wafa NM. The Relation between Smoking and Intraocular Pressure. Benha Journal of Applied Sciences. 2024;9(7):91-5.\u003c/li\u003e\n\u003cli\u003eSharif NA. Therapeutic drugs and devices for tackling ocular hypertension and glaucoma, and need for neuroprotection and cytoprotective therapies. Frontiers in pharmacology. 2021;12:729249.\u003c/li\u003e\n\u003cli\u003eMaurya RP, Gupta A, Verma S, Singh V, Singh A, Singh V, et al. Sex hormones and dry eye disease: Current update. IP Int J Ocul Oncol Oculoplasty. 2021;7(2):139-50.\u003c/li\u003e\n\u003cli\u003eAfzal S, Affi A, Siddique M, Rashid F, Aslam M, Jabbar M. Impact of Oral Contraceptive Pills on Intraocular Pressure and Central Corneal Thickness in Young Women. Pakistan Journal of Medical \u0026amp; Health Sciences. 2022;16(08):267-.\u003c/li\u003e\n\u003cli\u003eMalik TG, Alam HNEAR. Effect of short-term use of oral contraceptive pills on intraocular pressure. Pakistan Journal of Ophthalmology. 2019;35(3).\u003c/li\u003e\n\u003cli\u003eKamil Z, Qurban Q, Mahmood K. Effect of Oral Contraceptive Pills on Tear Film Status and Intraocular Pressure. Pakistan Journal of Ophthalmology. 2021;37(2).\u003c/li\u003e\n\u003cli\u003eWang YE, Kakigi C, Barbosa D, Porco T, Chen R, Wang S, et al. Oral contraceptive use and prevalence of self-reported glaucoma or ocular hypertension in the United States. Ophthalmology. 2016;123(4):729-36.\u003c/li\u003e\n\u003cli\u003eBhanwra S, Ahluwalia K. The association of oral contraceptive pills with increase in intraocular pressure: Time for pharmacovigilance to step in. Journal of Pharmacology and Pharmacotherapeutics. 2015;6(1):51-2.\u003c/li\u003e\n\u003cli\u003eCheraghian B, Hashemi SJ, Hosseini SA, Poustchi H, Rahimi Z, Sarvandian S, et al. Cohort profile: The Hoveyzeh Cohort Study (HCS): A prospective population-based study on non-communicable diseases in an Arab community of Southwest Iran. Medical journal of the Islamic Republic of Iran. 2020;34:141.\u003c/li\u003e\n\u003cli\u003eAlipour F, Hashemi H, Lashay A, Jafari F, Motamed-Gorji N, Behrouz MJ, et al. PERSIAN Eye Cohort Study (PECS): Design, methodology. Archives of Iranian Medicine. 2023;26(8):459.\u003c/li\u003e\n\u003cli\u003eHashemi SJ, Khezri R, Saki N, Nasehi N, Hosseini SA, Harizi M, et al. Association between oral contraceptives with lipid profile: results from Hoveyzeh cohort study (HCS). BMC Women\u0026apos;s Health. 2023;23(1):552.\u003c/li\u003e\n\u003cli\u003eMachiele R, Motlagh M, Zeppieri M, Patel BC. Intraocular Pressure. StatPearls. Treasure Island (FL) ineligible companies. Disclosure: Mahsaw Motlagh declares no relevant financial relationships with ineligible companies. Disclosure: Marco Zeppieri declares no relevant financial relationships with ineligible companies. Disclosure: Bhupendra Patel declares no relevant financial relationships with ineligible companies.: StatPearls Publishing Copyright \u0026copy; 2025, StatPearls Publishing LLC.; 2025.\u003c/li\u003e\n\u003cli\u003eRoberts-Lewis SF, White CM, Ashworth M, Rose MR. The validity of the International Physical Activity Questionnaire (IPAQ) for adults with progressive muscle diseases. Disability and rehabilitation. 2022;44(23):7312-20.\u003c/li\u003e\n\u003cli\u003eDe Leo V, Musacchio MC, Cappelli V, Piomboni P, Morgante G. Hormonal contraceptives: pharmacology tailored to women\u0026apos;s health. Human reproduction update. 2016;22(5):634-46.\u003c/li\u003e\n\u003cli\u003eDaniels K. Current Contraceptive Status Among Women Aged 15-44;: United States, 2011-2013: US Department of Health and Human Services, Centers for Disease Control and \u0026hellip;; 2014.\u003c/li\u003e\n\u003cli\u003eMadjedi KM, Stuart KV, Chua SY, Foster PJ, Strouthidis NG, Luben RN, et al. The association of female reproductive factors with glaucoma and related traits: a systematic review. Ophthalmology Glaucoma. 2022;5(6):628-47.\u003c/li\u003e\n\u003cli\u003eFortepiani L, Foutch BK, Wilson MR. The effects of sex, oral contraception, and menstrual cycle phase on intraocular pressure, central corneal thickness, and foveal thickness: a descriptive analysis. Vision. 2021;5(4):48.\u003c/li\u003e\n\u003cli\u003eUwagboe PN, Uwagboe CU, Mba CR. Effects of injectable contraceptives on intraocular pressure among women of child bearing age. International Journal of Reproduction, Contraception, Obstetrics and Gynecology. 2021;10(2):444-7.\u003c/li\u003e\n\u003cli\u003ePai SR, Shenoy JP, Kole SB. Postmenopausal intraocular pressure changes in South Indian females. Journal of clinical and diagnostic research: JCDR. 2013;7(7):1322.\u003c/li\u003e\n\u003cli\u003eMahlab Ijaz EL, Rai Muhammad Azam, Bisma Shaheen, Smer Yasmeen, Ayesha Arshad, Asif Saeed, \u0026amp; Shafia Arshad. ASSOCIATION OF CATARACT, CORNEAL THICKNESS AND INTRAOCULAR PRESSURE WITH DIFFERENT CONTRACEPTIVE METHODS IN FEMALES. Journal of Population Therapeutics and Clinical Pharmacology. 2023;30(18):2585-96.\u003c/li\u003e\n\u003cli\u003eMoschos MM, Nitoda E. The impact of combined oral contraceptives on ocular tissues: a review of ocular effects. International journal of ophthalmology. 2017;10(10):1604-10.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Oral Contraceptive Pills, Intraocular Pressure, Adult, Iran","lastPublishedDoi":"10.21203/rs.3.rs-6674113/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6674113/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eOral contraceptive pills (OCP) contain hormones that may affect various physiological parameters, including intraocular pressure (IOP). The primary goal of this study was to examine the relationship between OCP use and IOP in women in southwestern Iran. Additionally, we sought to explore associations between IOP, body mass index (BMI), hypertension, and cigarette smoking within this population.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eThis population-based cross-sectional study was conducted as part of the baseline of the Adult and Eye Hoveyzeh cohort study in women aged 35\u0026ndash;50 in southwest Iran between 2016 and 2021. Information on socioeconomic factors, demographic characteristics, comorbidities, and family history of glaucoma was collected. Analysis of Covariance was used to compare means between groups while controlling for the effects of covariates.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eOf the 746 participants, 656 (87.9%) were oral contraceptive pill users. An independent \u003cem\u003et\u003c/em\u003e-test found no significant difference in IOP between OCP users (\u003cem\u003eM\u003c/em\u003e\u0026thinsp;=\u0026thinsp;12.45, \u003cem\u003eSD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.13) and non-users (\u003cem\u003eM\u003c/em\u003e\u0026thinsp;=\u0026thinsp;12.38, \u003cem\u003eSD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.11), \u003cem\u003et\u003c/em\u003e (723)\u0026thinsp;=\u0026thinsp;0.289, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.773. Additionally, no significant correlation was found between the duration of OCP use and IOP (\u003cem\u003er\u003c/em\u003e = -0.04, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.348). An ANCOVA adjusting for age, hypertension, family history of glaucoma, and BMI confirmed that OCP use had no significant effect on IOP (\u003cem\u003eF\u003c/em\u003e (1, 721)\u0026thinsp;=\u0026thinsp;0.060, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.806, partial η\u0026sup2; \u0026lt; 0.001). These findings suggest that OCP use does not influence IOP.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis study found no significant association between OCP and IOP, but highlights the importance of healthcare providers and patients being aware of potential glaucoma risks and monitoring any changes in IOP.\u003c/p\u003e","manuscriptTitle":"Oral Contraceptive Use and Intraocular Pressure: Findings from a Population-Based Cross-Sectional Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-04 10:14:28","doi":"10.21203/rs.3.rs-6674113/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-06-26T12:18:34+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-20T20:58:28+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-17T09:19:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"32283210770261420537027794078524947599","date":"2025-06-16T04:55:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"279839054642873310571582607004793349900","date":"2025-06-15T19:54:46+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-01T21:19:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-01T20:59:37+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-05-28T08:42:24+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-28T06:46:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Ophthalmology","date":"2025-05-28T06:45:19+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"32e49e6b-4210-426b-bb56-0b6ddb9179cb","owner":[],"postedDate":"June 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-10-13T16:03:44+00:00","versionOfRecord":{"articleIdentity":"rs-6674113","link":"https://doi.org/10.1186/s12886-025-04413-0","journal":{"identity":"bmc-ophthalmology","isVorOnly":false,"title":"BMC Ophthalmology"},"publishedOn":"2025-10-06 15:57:37","publishedOnDateReadable":"October 6th, 2025"},"versionCreatedAt":"2025-06-04 10:14:28","video":"","vorDoi":"10.1186/s12886-025-04413-0","vorDoiUrl":"https://doi.org/10.1186/s12886-025-04413-0","workflowStages":[]},"version":"v1","identity":"rs-6674113","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6674113","identity":"rs-6674113","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}