Low Serum Level of Vitamin D is Associated with Uterine Leiomyoma in the Chinese Population

Background: The goal of this work was to compare the serum vitamin D level in women with uterine leiomyoma to that of controls, and to examine its association with the etiopathogenesis of this disease. Methods: This case-control study included 110 premenopausal women referred to a university hospital from January 2020 to December 2020. The study group consisted of 55 cases who underwent surgery for uterine fibroids, while the control group was comprised of 55 subjects without uterine fibroids. The number and volume of existing fibroids in each subject was assessed by transvaginal ultrasonography. Serum vitamin D status was determined by radioimmunoassay for 25-hydroxyvitamin D. Results: Average serum 25-hydroxyvitamin D levels in patients with uterine fibroids (20.52 ± 6.17 ng/mL) were significantly lower than in controls (24.18 ± 6.88 ng/mL; p = 0.004). Deficiency in 25-hydroxyvitamin D (i.e.,