VDR and Dysmenorrhea: Two hundred and five (205) adolescents between 12–18 years-old complaining of PD [study group (dysmenorrhea group)] were compared in this prospective study to matched controls (210 adolescents without dysmenorrhea) to detect the relation between serum 25(OH)D and PD, and the odds of PD in Asian adolescents with VDR TaqI polymorphism.