Abstract
PurposeTo determine the influence of menstrual irregularity, oral contraceptive use and other factors on bone mineral density (BMD) and bone size at different skeletal sites in 135 college-aged fit women.MethodsMenstrual history, oral contraceptive use, exercise history, and nutritional factors including calcium, caffeine, and alcohol intake as well as tobacco use were determined by written survey. Height, weight and fitness levels were measured. Spine and hip BMD were measured by dual x-ray absorptiometry (DXA), calcaneus BMD by peripheral DXA, and tibial bone mineral content (BMC) and size by peripheral Quantitative Computed Tomography (pQCT).ResultsThe mean age was 18.4 ± 0.8 years. Weight and prior exercise were positively related to BMD at most skeletal sites and to tibial bone size. Milk intake was positively related to calcaneal BMD, tibial BMC and cortical thickness. Fracture history was an important predictor of spine, hip and heel BMD. Women who had ≥ 10 menstrual cycles in the year prior to BMD measurement had higher BMD at all sites as well as a greater tibial mineral content and cortical thickness than women who had oligomenorrhea/amenorrhea (≤ 9 cycles in the prior year; all p < 0.05). Oral Contraceptive (OC) users had significantly lower BMD in the spine (p < 0.02) and calcaneus (p = 0.04), smaller tibial periosteal circumference and lower tibial mineral content (p < 0.02) than non-OC users.ConclusionIn a population of fit, college-aged women, OC use and oligomenorrhea were associated with reduced BMD and bone size. Weight, as well as prior exercise and milk intake was positively related to bone density and size at some skeletal sites. Understanding these relationships would help improve skeletal health in young women.
Highlights
Osteoporosis is a major public health concern as highlighted by the recent Surgeon General's report [1]
We found that one of the strongest negative predictors of bone density was oligomenorrhea that occurred in 13% of women or amenorrhea that occurred in 5% of this population
Cortical thickness can be increased by apposition of endocortical bone but in females with oligomenorrhea/ amenorrhea this may be prevented, and may in part explain the significantly larger endosteal circumference we found in women who have abnormal menstrual function
Summary
Osteoporosis is a major public health concern as highlighted by the recent Surgeon General's report [1]. A key osteoporosis prevention strategy is to increase early accrual of bone mineral density (BMD). It is important to understand factors that can be modified to improve the accrual of peak bone mass and increase in bone size in women [6,7,8]. Oral contraceptive (OC) use may have an effect on bone accrual but its exact role is unclear. Several recent studies have shown either no effect or negative effects of oral contraceptives on bone density. Observational studies of OC use on bone mass may be confounded by the underlying reason for use as 4–9% of women use oral contraceptives for reasons other than birth control, including amenorrhea or oligomenorrhea [18]. There are many other factors that may positively influence BMD including high levels of physical activity and adequate calcium intake [6,19,20]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
