Abstract
BackgroundIn South Africa, hormonal contraception is widely used in women over the age of 40 years. One of these methods and the most commonly used is depot-medroxyprogesterone acetate (DMPA) which has been found to have a negative effect on bone mass. Limited information is available on the effect of norethisterone enanthate (NET-EN) on bone mass, and combined oral contraceptives (COCs) have not been found to be associated with loss of bone mass. The aim of this study was to investigate bone mineral density (BMD) in pre and perimenopausal women (40–49 years) in relation to use of DMPA, NET-EN and COCs for at least 12 months preceding recruitment into the study and review associations with body mass index (BMI) and menopausal status.MethodsOne hundred and twenty seven users of DMPA, 102 NET-EN users and 106 COC users were compared to 161 nonuser controls. Menopausal status was assessed, BMI and forearm BMD was measured at the distal radius using dual X-ray absorptiometry. Comparison analysis was conducted at baseline and 2.5 years.ResultsThere was no significant difference in BMD between the four contraceptive user groups (p = 0.26) with and without adjustment for age at baseline or at 2.5 years (p = 0.52). The BMD was found to be significantly associated with BMI (p = < 0.0001) with an increase of one unit of BMI translating to an increase of 0.0044 g/cm2 in radius BMD. Follicle stimulating hormone (FSH) level ≥ 25.8 mIU/mL was associated with a decrease of 0.017 g/cm2 in radius BMD relative to women with FSH < 25.8 mIU/mL. Significant interaction between FSH and BMI in their effect on BMD was observed (p = .006).ConclusionThis study found no evidence that long-term use of DMPA, NET-EN and COCs affects forearm BMD in this population at baseline or after 2.5 years of follow-up. This study also reports the complex relationship and significant interaction between FSH and BMI in their effect on BMD. BMD research in older women needs to ensure that women are assessed for menopausal status and BMI.
Highlights
In South Africa, hormonal contraception is widely used in women over the age of 40 years
The populations investigated in previous studies looking at the effect of depot-medroxyprogesterone acetate (DMPA) and norethisterone enanthate (NET-EN) on bone mineral density (BMD) have included women using the method in their 40s but there is limited information in this age group
In one crosssectional study older DMPA users were disaggregated in the data [11] and no differences were found in BMD in women aged between 40 and 49 and a slightly older group of 50–52 compared to a normal population mean in the lumber spine and femoral neck
Summary
In South Africa, hormonal contraception is widely used in women over the age of 40 years One of these methods and the most commonly used is depot-medroxyprogesterone acetate (DMPA) which has been found to have a negative effect on bone mass. Of the two available hormonal injections, older women (> 40 years) almost exclusively use depot medroxyprogesterone acetate (DMPA) (81%) compared to norethisterone enanthate (NET-EN) (19%) [1]. These highly effective methods of contraception may be the method of choice for many women over 40 who have completed childbearing and are concerned about avoiding pregnancy. A recent Cochrane review concludes that existing information cannot confirm whether steroidal contraceptives influence future fracture risk [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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.
