Abstract
Oral contraceptives (OCs) are mostly used by women for a long period in their life during early reproductive years. According to the close relationship between estrogen and bone metabolism, the question of the impact of OCs on bones needs to be addressed. The purpose of this study was to evaluate the changes of bone turnover markers (BTMs) among healthy premenopausal Saudi women using OCs. Seventy-five females (24-40 years) were categorized as OCs users (N=40) for at least one year, and (N=35) non-contraceptive users (NOC), i.e. controls. All Subjects completed a questionnaire on lifestyle characteristics at the Maternity and Children's Hospital in Almasadeya in Jeddah City, which included demographics, age, height, weight, BMI, smoking history, caffeine use, milk consumption, vitamins D intake, supplement use, sun exposure, and exercise. Women with previous fractures, thyroid disease, hypertension and family history of osteoporosis were excluded. Main outcome measures included three markers of bone formation (osteocalcin, bone alkaline phosphatase (Bone ALP) and N-terminal propeptide of type I procollagen (PINP), and two markers of bone resorption that are Carboxy-terminal crosslinked telopeptide of collagen type I and N-terminal crosslinked telopeptide of type I collagen (NTXI). In addition, concentration of bone minerals (Calcium, Phosphorus and Magnesium), hormones and vitamin D3 levels were assessed. The mean serum bone minerals, parathyroid hormone (PTH) and vitamin D3 levels obtained from OCs users were slightly lower than those of the control group. Serum indicators of bone turnover were raised slightly among OCs users compared to the age-mate controls. However, increases in Bone serum ALP and serum CTX observed in OCs users were compared with NOC controls, but the results were still in normal range. It was concluded that BTMs were not significantly influenced by using OCs in premenopausal Saudi women.