Serum alkaline phosphatase and bone mineral density: to assess bone loss in oral contraceptive pill user

An analytic cross-sectional retrospective study was done in the Department of Pharmacology BSMMU. In collaboration with the Department of Obstetric and Gynecology and Department of Biochemistry of BSSMU, Dhaka to define any relation between the oral combined pill (OCP), bone mineral density (BMD) and serum alkaline phosphatase in pre and post menopausal women. A total of 100 closely matched healthy women were selected non-randomly. The age range was 35-55 years. Among them 50 were controls or nonuser and 50 were case or users of OCP. They were further subdivided into pre and postmenopausal groups. Bone density of the 100 women was measured in distal radius and ulna by single photon Absorptiometry Bone Densitometer DTX-100. Serum alkaline phosphatase was measured by reaction principle spectrophotometer UV 1201 Shimadzu by optimized standard method. It was found in this study that OCP users both pre and post menopausal women had lower level of mean alkaline phosphatase and higher mean BMD compared to non-users who had higher level of mean alkaline phosphatase and lower mean BMD. These data indicates that OCP non-users had elevated bone turn over, which appears to adversely influence BMD and fracture risk. It can be concluded that the most important non-contraceptive benefit of OCP may be positive effects on bone mass and combined biochemical and BMD screening may provide better prediction of future fracture risk than BMD alone.