The Association between Vitamin D Level and Uterine Fibroid in Premenopausal Women in a Tertiary Care Centre: A Hospital-Based Analytical Case-Control Study

Abstract

Background: Uterine fibroids are the most common benign smooth muscle tumors of the uterus and constitute a major cause of gynecological morbidity among women of reproductive age. Although their exact pathogenesis remains incompletely understood, increasing evidence suggests that vitamin D deficiency may contribute to fibroid development through its effects on cellular proliferation, apoptosis, extracellular matrix remodeling, and angiogenesis. Since vitamin D deficiency is highly prevalent among Indian women, understanding its relationship with uterine fibroids may provide opportunities for preventive and therapeutic interventions.
Objective: To evaluate the association between serum vitamin D levels and uterine fibroids among premenopausal women attending a tertiary care hospital and to assess the relationship between vitamin D status and fibroid characteristics.
Materials and Methods: A hospital-based analytical case-control study was conducted in the Department of Obstetrics and Gynaecology, MDM Hospital, Dr.Sampurnanand Medical College, Jodhpur, Rajasthan, over a period of six months. Fifty premenopausal women were enrolled, comprising 25 ultrasound-confirmed uterine fibroid cases and 25 age-matched controls without fibroids. Demographic, clinical, menstrual, and obstetric characteristics were recorded using a structured proforma. Serum 25-hydroxyvitamin D concentration was estimated by standard laboratory methods and categorized as deficient (<20 ng/mL), insufficient (20–29 ng/mL), and sufficient (≥30 ng/mL). Fibroid characteristics including type, number, and volume were assessed by ultrasonography. Statistical analysis was performed using SPSS software. Categorical variables were analyzed using the Chi-square test, while continuous variables were compared using the independent t-test. A p-value <0.05 was considered statistically significant.
Results: The mean age of cases and controls was 38.36 ± 3.67 years and 37.92 ± 4.79 years, respectively (p=0.452). Mean serum vitamin D levels were significantly lower among women with uterine fibroids than controls (12.43 ± 4.20 vs. 17.19 ± 5.65 ng/mL, p=0.001). Vitamin D deficiency was significantly more common in cases than controls (32.0% vs. 4.0%; p=0.028). Mean haemoglobin levels were also significantly lower among cases (10.08 ± 1.46 g/dL) than controls (11.18 ± 1.93 g/dL; p=0.029). Intramural fibroids constituted the commonest subtype (68%), while single fibroids were observed in 64% of cases. Significant associations were identified between vitamin D status and fibroid type (p=0.013) as well as fibroid number (p=0.031). However, no statistically significant association was observed between vitamin D status and fibroid volume (p=0.499).
Conclusion: Premenopausal women with uterine fibroids demonstrated significantly lower serum vitamin D levels than women without fibroids. Vitamin D deficiency was associated with the presence of uterine fibroids and showed significant relationships with fibroid type and multiplicity. These findings suggest that vitamin D deficiency may represent an important modifiable risk factor in uterine fibroid pathogenesis. Larger prospective multicentric studies are warranted to establish causality and evaluate the potential role of vitamin D supplementation in the prevention and management of uterine fibroids.