Vitamin D and uterine fibroid growth, incidence, and loss: a prospective ultrasound study

Nonlinear correlation between serum vitamin D levels and the incidence of endometrial polyps in infertile women

STUDY QUESTION

Are serum vitamin D levels associated with the incidence of endometrial polyps (EPs) in infertile patients?

SUMMARY ANSWER

Serum 25(OH)D levels were nonlinearly correlated with the incidence of EPs in infertile women.

WHAT IS KNOWN ALREADY

EPs are a common condition that may affect the receptivity of the endometrium in women of reproductive age. Vitamin D regulates cell proliferation and differentiation, apoptosis, angiogenesis, anti-inflammation, and immunomodulation, in addition to its well-known functions in balancing calcium and phosphorus. Previous studies have shown that vitamin D concentrations are associated with reproductive outcomes, and that low vitamin D levels are associated with the incidence of colorectal polyps and nasal polyps. There is little evidence regarding the relationship between EPs and serum vitamin D levels.

STUDY DESIGN, SIZE, DURATION

We conducted a cross-sectional study using data from Guangdong Women and Children Hospital from January 2019 to October 2023, enrolling 3107 patients.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 3107 infertile patients who underwent hysteroscopy were included in this study; 642 patients had endometrial polyps and 2465 had a normal uterine cavity. Hysteroscopy findings included risk of EPs, polyp size, percentage of multiple polyps, and incidence of chronic endometritis (CE). Serum vitamin D were assessed by measuring total 25(OH)D using chemiluminescence. According to international guideline recommendations for vitamin D deficiency, patients were divided into two groups: the <50 nmol/l group and the ≥50 nmol/l group. Univariable and multivariable logistic regression models, stratified analyses, and smooth curve fitting were used to examine the relationship between serum 25(OH)D levels and risk of EPs.

MAIN RESULTS AND THE ROLE OF CHANCE

Of all patients, 23.8% (740/3107) were vitamin D deficient (<50 nmol/l). The incidence of EPs was significantly higher in the 25(OH)D < 50 nmol/l group than in the ≥50 nmol/l group (24.9% vs 19.3%; P = 0.001). However, there were no differences in polyp size, proportion of multiple polyps, and presence of CE between the two groups. After controlling for confounders, 25(OH)D ≥ 50 nmol/l (compared with <50 nmol/l) was negatively associated with risk of EPs (adjusted OR, 0.733; 95% CI, 0.598-0.898). Other variables that had an impact on polyp incidence included BMI, type of infertility, CA125, and CD138-positive plasma cells. In addition, a linear regression model between age and serum 25(OH)D levels showed a positive linear association. Subgroup analyses were performed for different age groups, and the risk of EPs was significantly higher in the 25(OH)D < 50 nmol/l group than in the ≥50 nmol/l group, both in the younger subgroup (23.8% vs 19.1%) and in the older subgroup (28.0% vs 19.9%). The smooth curve fitting model showed a nonlinear correlation between 25(OH)D levels and risk of EPs (nonlinear P-value = 0.020), with an optimal threshold of 51.8 nmol/l for 25(OH)D levels. Moreover, subgroup smooth curve fitting models showed a nonlinear correlation between 25(OH)D levels and polyp risk in patients aged <35 years (nonlinear P-value = 0.010), whereas a linear correlation between 25(OH)D levels and polyp risk was found in patients aged ≥35 years (nonlinear P-value = 0.682).

LIMITATIONS, REASONS FOR CAUTION

Caution should be exercised in interpreting our findings as this is a correlational study and causality cannot be inferred from our results. In addition, because of strict inclusion and exclusion criteria, our results may not be generalizable to unselected populations, including premenopausal women or women of other races.

WIDER IMPLICATIONS OF THE FINDINGS

This study demonstrated for the first time that vitamin D deficiency is an independent risk factor for the incidence of EPs in infertile patients. Identifying modifiable risk factors (e.g. vitamin D deficiency) can help in the development of new strategies for treating polyps or to protect against polyp development. Further clinical intervention trials and laboratory studies are needed to evaluate the effect of vitamin D on the development of EPs and to elucidate the mechanisms.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the National Natural Science Foundation of China (82101718) and Natural Science Foundation of Guangdong Province, China (2022A1515010776). No competing interest was involved in this study.

TRIAL REGISTRATION NUMBER

N/A.

Body Mass Index and Uterine Fibroid Development: A Prospective Study

OBJECTIVE

Fibroids are hormonally dependent uterine tumors. The literature on adiposity and fibroid prevalence is inconsistent. Previous work usually combined all those with a body mass index (BMI) ≥30 kg/m2 into a single category and relied on clinically diagnosed fibroids, which misclassifies the many women with undiagnosed fibroids. We used a prospective cohort design with periodic ultrasound screening to investigate associations between repeated measures of BMI and fibroid incidence and growth assessed at each follow-up ultrasound.

METHODS

The Study of Environment, Lifestyle & Fibroids followed 1693 Black/African American women, ages 23 to 35 years from Detroit, Michigan, with ultrasound every 20 months for 5 years. Measured height and repeated weight measures were used to calculate BMI. Fibroid incidence was modeled using Cox models among those who were fibroid free at the enrollment ultrasound. Fibroid growth was estimated for individual fibroids matched across visits as the difference in log-volume between visits and was modeled using linear mixed models. All models used time-varying BMI and adjusted for time-varying covariates.

RESULTS

Compared with BMI <25 kg/m2, those with BMI 30 to <35 kg/m2 had increased fibroid incidence (adjusted hazard ratio, 1.37; 95% CI, 0.96-1.94), those with BMI ≥40 kg/m2 had reduced incidence (adjusted hazard ratio, 0.61; 95% CI, 0.41-0.90). Fibroid growth had mostly small magnitude associations with BMI.

CONCLUSION

BMI has a nonlinear association with fibroid incidence, which could be driven by effects of BMI on inflammation and reproductive hormones. More detailed measures of visceral and subcutaneous adiposity and their effects on hormones, DNA damage, and cell death are needed.

The Association of Vitamin D with Uterine Fibroids in Premenopausal Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

This study aims to consolidate existing literature regarding the association between vitamin D and uterine fibroid presence and growth.

DATA SOURCES

A comprehensive search across databases including Medline, Embase, CINAHL, Web of Science, ClinicalTrials.gov, and grey literature was conducted from inception to February 2023, using relevant keywords. Authors were contacted for unpublished data.

STUDY SELECTION

From 9931 studies screened based on title and abstract, those evaluating serum vitamin D levels or vitamin D treatment effects, using ultrasonography for diagnosis, and involving at least 25 premenopausal participants were included. Case reports, case series, and reviews were excluded.

DATA EXTRACTION AND SYNTHESIS

Data were extracted using a predefined form. Methodological quality was assessed through the Newcastle-Ottawa Scale and the Risk of Bias-2 tools. Evidence quality was evaluated using Grading of Recommendations Assessment, Development, and Evaluation. Data from 3 randomised controlled trials (n = 328) and 23 observational studies (n = 5650) were meta-analyzed via random-effects modelling. Patients receiving oral vitamin D supplementation had a significantly different change in fibroid size (standardized mean difference -5.7%; CI -10.63 to -0.76, P = 0.02, I2 = 99%), as measured by the percentage change in diameter or volume, compared to controls, over the span of 2-6 months. Those receiving supplementation had vitamin D insufficiency; regimens varied between 50 000 IU weekly for 12 weeks, 50 000 IU weekly for 8 weeks, and 50 000 IU biweekly for 10 weeks. Patients with fibroids exhibited lower serum vitamin D concentrations (mean difference -5.50 ng/mL; CI 6.99 to -4.01, P < 0.001, I2 = 87%) and higher odds of vitamin D deficiency (OR 3.71; CI 1.90-7.24, P < 0.001, I2 = 80%).

CONCLUSION

This review underscores the potential of vitamin D in mitigating fibroid development and growth. While promising, further research is warranted to optimise dosage and treatment duration, potentially offering a non-invasive solution for at-risk patients. Continued exploration of vitamin D's role in fibroid treatment is encouraged.

Associations of per- and polyfluoroalkyl substances with uterine leiomyomata incidence and growth: a prospective ultrasound study

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals used in commercial and consumer products.

OBJECTIVE

We evaluated PFAS exposure in relation to incidence and growth of uterine leiomyomata (UL), hormone-dependent neoplasms that are associated with severe gynecologic morbidity.

METHODS

We studied 1158 participants in the Study of Environment, Lifestyle, and Fibroids, a Detroit-based prospective cohort study of Black females aged 23-35 years at enrollment (2010-2012). At enrollment and four subsequent visits during 10 years of follow-up, participants attended in-person clinic visits, completed questionnaires, provided non-fasting blood samples, and underwent ultrasound for UL detection. We quantified 7 PFAS in baseline plasma samples using mass spectrometry. We used Cox regression and probit Bayesian kernel machine regression to estimate individual and joint effects of PFAS on UL incidence. We fit linear mixed models to estimate effects of individual PFAS on UL growth. We stratified by parity, an important route of PFAS elimination and determinant of UL.

RESULTS

In individual PFAS analyses, we observed inverse associations for perfluorodecanoate (PFDA; ≥0.3 vs. <0.2 ng/ml: hazard ratio [HR] = 0.74; 95% confidence interval [CI]: 0.54-1.00) and perfluoroundecanoate (detected vs. non-detected: HR = 0.78; 95% CI: 0.61-1.01) and a weak positive association for perfluorohexane sulfonate (≥1 vs. <0.6 ng/ml: HR = 1.17; 95% CI: 0.85-1.61), while perfluorooctane sulfonate, perfluorooctanoate, perfluorononanoate (PFNA), and 2-N-methyl-perfluorooctane sulfonamido acetate (MeFOSAA) showed little association with UL incidence. The PFAS mixture was inversely associated with UL incidence, a finding driven by MeFOSAA and PFDA; however, PFNA was positively associated with UL incidence. The inverse association for PFDA and positive association for PFNA were stronger among nulliparous participants. Most PFAS showed slight inverse associations with UL growth.

IMPACT STATEMENT

In this prospective ultrasound study of 1158 Black females aged 23-35 years at enrollment, we conducted a mixtures analysis to account for co-pollutant confounding and interaction. MeFOSAA and PFDA concentrations were inversely associated with UL incidence, while PFNA concentrations were positively associated with UL incidence. Concentrations of most PFAS were associated with decreased UL growth. This study contributes data to the sparse literature on PFAS exposure and UL development.

Association between serum 25-hydroxyvitamin D and antimüllerian hormone levels in a cohort of African-American women

OBJECTIVE

To examine the association between serum 25-hydroxyvitamin D [25(OH)D] levels and ovarian reserve as measured using antimüllerian hormone (AMH) levels.

DESIGN

Cross-sectional study.

SETTING

Detroit, Michigan area.

PATIENTS

Data were obtained from a prospective cohort of self-identified Black or African American women aged 23-35 years at the time of enrollment (N = 1,593), who had no prior diagnosis of polycystic ovary syndrome, were not currently pregnant, and were not missing AMH or 25(OH)D level measures.

INTERVENTION

Serum 25(OH)D.

MAIN OUTCOME MEASURE(S)

The serum AMH level was the main outcome. Linear regression was used to examine the associations between categorical 25(OH)D levels (<12, 12-<20, 20-<30, and ≥30 ng/mL) and continuous natural log-transformed AMH levels. Associations between 25(OH)D and high (upper 10th percentile: >7.8 ng/mL) or low AMH (<0.7 ng/mL) levels were estimated with logistic regression. Models were adjusted for age, age-squared, body mass index (kg/m2), hormonal contraceptive use, smoking, and exercise.

RESULTS

The 25(OH)D levels were low; 70% of participants were below 20 ng/mL. In fully adjusted models, compared with 25(OH)D levels <12 ng/mL, those with 25(OH)D levels of 12-<20, 20-<30, and ≥30 ng/mL had an AMH level that was 7% (95% confidence interval [CI]: -4, 20), 7% {95% CI: -6, 22}, or 11% {95% CI: -7, 34} higher, respectively. Moreover, these groups had lower odds of having low AMH levels (odds ratio [95% CI]: 0.63 {0.40, 0.99}, 0.60 {0.34, 1.07}, and 0.76 {0.35, 1.65}, respectively), and the highest category of 25(OH)D levels had higher odds of having high AMH levels (odds ratio [95% CI]: 1.42 {0.74, 2.72}). Exclusion of participants with either irregular cycles or very high AMH (>25 ng/mL) levels did not alter the associations.

CONCLUSION

Taken together, these results indicate that higher levels of 25(OH)D are associated with slightly higher AMH levels, lower odds of low AMH levels, and higher odds of high AMH levels. This evidence is weak, however, because only a small percentage of participants had high 25(OH)D levels. Future studies should examine populations with a wide distribution of 25(OH)D levels (both high and low), with a clinical trial design, or with longitudinal measures of both 25(OH)D and AMH levels.

The Role of Nutrition in Pathogenesis of Uterine Fibroids

Uterine fibroids are benign tumors that arise from the smooth muscle tissue of the uterus and are the most common tumors in women. Due to their high prevalence, costs for the health care system and the substantial impact on women's quality of life, they are a significant public health concern. Previous literature on the impact of diet on the occurrence, growth and symptoms of fibroids is limited. Recently, many papers have been written on this topic. A scoping review of PubMed and Cochrane databases was performed using the following keywords: uterine fibroids, antioxidants, diet, diet, vegetarian, vegetables, fruits, meat and soy foods, dairy products, tea, vitamin D, vitamin C, ascorbic acid. Preliminary research has shown a beneficial effect of vegetable and fruit consumption on the occurrence of fibroids. A relationship between hypovitaminosis D and an increased risk of fibroids has also been demonstrated. Studies on epigallocatechin gallate showed its apoptosis-promoting and antifibrinolytic effect in fibroid cells. Initial results are promising, but further randomized trials are needed to draw firm conclusions about the effects of diet and nutrients on uterine fibroids.

Evidence-Based Approach for Secondary Prevention of Uterine Fibroids (The ESCAPE Approach)

Uterine fibroids (UFs) are common tumors in women of reproductive age. It is imperative to comprehend UFs' associated risk factors to facilitate early detection and prevention. Simple relying on surgical/pharmacological treatment of advanced disease is not only highly expensive, but it also deprives patients of good quality of life (QOL). Unfortunately, even if the disease is discovered early, no medical intervention is traditionally initiated until the disease burden becomes high, and only then is surgical intervention performed. Furthermore, after myomectomy, the recurrence rate of UFs is extremely high with the need for additional surgeries and other interventions. This confused approach is invasive and extremely costly with an overall negative impact on women's health. Secondary prevention is the management of early disease to slow down its progression or even halt it completely. The current approach of watchful observation for early disease is considered a major missed opportunity in the literature. The aim of this article is to present an approach named the ESCAPE (Evidence-Based Approach for Secondary Prevention) of UF management. It comprises simple, inexpensive, and safe steps that can arrest the development of UFs, promote overall reproductive health, decrease the number of unnecessary surgeries, and save billions of health care systems' dollars worldwide.

Vitamin D and infertility

PURPOSE OF REVIEW

Vitamin D deficiency has been implicated as a contributing factor to a spectrum of reproductive health burden, including difficulty conceiving, pathogenesis of gynaecological disorders such as uterine fibroids and endometriosis, to metabolic and endocrine burden of polycystic ovarian syndrome (PCOS).

RECENT FINDINGS

There have been recent publications showing that in infertile women who are supplemented with vitamin D, there are higher pregnancy rates; there are improved ovarian reserve parameters in women with diminished ovarian reserve; curtailed fibroid growth in those with uterine myomas; lessened dysmenorrhea in endometriosis patients; and improved menstrual regularity, lowered testosterone, AMH and insulin levels in women with PCOS. In infertile men, sperm parameters, especially motility, are positively correlated with vitamin D serum levels.

SUMMARY

Vitamin D status appears to be relevant to reproductive physiology, and to physiological processes underlying common gynaecological disorders as well as for reproductive success.

Presence of Fibroids on Transvaginal Ultrasonography in a Community-Based, Diverse Cohort of 996 Reproductive-Age Female Participants

Importance

Fibroids are benign uterine tumors that can cause significant morbidity. Knowledge on fibroid prevalence, especially in the asymptomatic population and in Asian and Hispanic or Latina individuals, is limited, and a better understanding of affected groups will improve timely diagnosis and motivate appropriate recruitment in clinical trials to reduce health disparities.

Objective

To estimate the prevalence of fibroids in a diverse cohort of female individuals.

Design, Setting, and Participants

This cross-sectional study included female individuals not seeking treatment for fertility or other conditions who were prospectively recruited in an academic medical center in San Francisco, California. Effort was made to recruit an equal proportion of participants from 4 large racial and ethnic groups in the United States (Asian-Chinese, Black or African American, Hispanic or Latina, and White) and across 4 equal age groups between 25 and 45 years. All participants reported regular menses (21-35 days), had not used estrogen- or progestin-containing medications in the 3 months prior to enrollment, and denied history of pelvic surgery. The assessment of ultrasonography results was part of an ongoing longitudinal cohort, with initial recruitment from October 2006 to September 2012. Data analysis was performed in April to September 2022.

Main Outcomes and Measures

Fibroid presence and burden as assessed by transvaginal ultrasonography.

Results

A total of 996 female participants were included in the analysis, including 229 (23.0%) Asian-Chinese, 249 (25.0%) Black or African American, 237 (23.8%) Hispanic or Latina, and 281 (28.2%) White individuals. Mean (SD) age was 34.8 (5.7) years in Asian-Chinese participants, 35.4 (6.1) years in Black or African American participants, 34.8 (5.3) years in Hispanic or Latina participants, and 35.3 (5.0) years in White participants. Fibroids were present in 21.8% (95% CI, 16.7%-27.8%) of Asian-Chinese participants, 35.7% (95% CI, 29.8%-42.0%) of Black or African American participants, 12.7% (95% CI, 8.7%-17.6%) of Hispanic or Latina participants, and 10.7% (95% CI, 7.3%-14.9%) of White participants. Black or African American and Asian-Chinese participants were more likely to have fibroids than White participants (Black or African American: adjusted odds ratio [OR], 4.72 [95% CI, 2.72-8.18]; P < .001; Asian-Chinese: adjusted OR, 3.35 [95% CI, 1.95-5.76]; P < .001). In those with fibroids, the proportion with multiple fibroids were 48.3% in Black or African American participants, 33.3% in White participants, 33.3% in Hispanic or Latina participants, and 26.0% in Asian-Chinese participants (P = .06). The largest mean (SD) fibroid diameter was 3.9 (1.9) cm in Black or African American participants, 3.2 (1.6) cm in Asian-Chinese participants, 3.2 (1.6) cm in White participants, and 3.0 (1.4) cm in Hispanic or Latina participants (P = .03).

Conclusions and Relevance

In this study of female participants in a nonclinical setting, Black or African American and Asian-Chinese participants were disproportionately affected by uterine fibroids. Hispanic or Latina participants had similar fibroid burden to White participants.

Prediction of postoperative reintervention risk for uterine fibroids using clinical-imaging features and T2WI radiomics before high-intensity focused ultrasound ablation

OBJECTIVE

To predict the risk of postoperative reintervention for uterine fibroids using clinical-imaging features and T2WI radiomics before high-intensity focused ultrasound (HIFU) ablation.

METHODS

Among patients with uterine fibroids treated with HIFU from 2019 to 2021, 180 were selected per the inclusion and exclusion criteria (42 reintervention and 138 non-reintervention). All patients were randomly assigned to either the training (n = 125) or validation (n = 55) cohorts. Multivariate analysis was used to determine independent clinical-imaging features of reintervention risk. The Relief and LASSO algorithm were used to select optimal radiomics features. Random forest was used to construct the clinical-imaging model based on independent clinical-imaging features, the radiomics model based on optimal radiomics features, and the combined model incorporating the above features. An independent test cohort of 45 patients with uterine fibroids tested these models. The integrated discrimination index (IDI) was used to compare the discrimination performance of these models.

RESULTS

Age (p < .001), fibroid volume (p = .001) and fibroid enhancement degree (p = .001) were identified as independent clinical-imaging features. The combined model had AUCs of 0.821 (95% CI: 0.712-0.931) and 0.818 (95% CI: 0.694-0.943) in the validation and independent test cohorts, respectively. The predictive performance of the combined model was 27.8% (independent test cohort, p < .001) and 29.5% (independent test cohort, p = .001) better than the clinical-imaging and radiomics models, respectively.

CONCLUSION

The combined model can effectively predict the risk of postoperative reintervention for uterine fibroids before HIFU ablation. It is expected to help clinicians to develop accurate, personalized treatment and management plans. Future studies will need to be prospectively validated.