Oral contraceptive use by teenage women does not affect peak bone mass: a longitudinal study

Hormonal Contraception and Bone Metabolism: Emerging Evidence from a Systematic Review and Meta-Analysis of Studies on Post-Pubertal and Reproductive-Age Women

BACKGROUND/OBJECTIVES

This study aims to assess the effects of combined hormonal contraceptives (CHCs) on bone metabolism markers. It primarily measures osteocalcin and additionally examines other bone health markers, seeking to determine their responses to estrogen-progestogen treatments.

METHODS

This study involved a comprehensive evaluation of the pertinent literature and a meta-analysis explicitly conducted on data describing women of reproductive age. The analysis encompassed accessible papers ranging to December 2024 (i.e., those listed in PubMed/Medline, Embase, Scopus, the Cochrane Database, International Clinical Trials Registry, and ClinicalTrials.gov). We examined published randomized controlled trials (RCTs) and prospective studies. The quality of the studies was assessed using the Cochrane tool for RCTs and the Newcastle-Ottawa Scale for prospective studies. The selected indicators for primary and secondary outcomes were ascertained by standardized mean change (SMC), displaying the difference between conditions before and after treatment. Trends were evaluated using meta-regressions.

RESULTS

Ultimately, 34 articles out of 1924 identified items met the inclusion criteria, covering 33 unique studies. In EE/E4 combinations, osteocalcin dropped significantly (SMC -0.54 (CI.95 -0.64/-0.43) and -0.43 (CI.95 -0.76/-0.10)). Similar effects were observed for other bone-formation and reabsorption markers, with less significant reductions observed in E2-containing CHC (e.g., alkaline phosphatase (bone) EE combinations, SMC -0.39 (CI.95 -0.67/-0.11); P1NP E2 combination, 0.12 (CI.95 -0.10/0.33); and EE combinations, -0.55 (CI.95 -0.83/-0.26)). The reduction patterns also exhibited differences according to the women's age (e.g., osteocalcin in EE combinations ≤21, SMC -0.63 (CI.95 -0.77/-0.49) and >21, SMC -0.42 (CI.95 -0.61/-0.24); alkaline phosphatase (bone) EE combinations ≤21, SMC -0.55 (CI.95 -0.86/-0.24) and >21, SMC -0.06 (CI.95 -0.47/0.35)). This analysis found that CHC maintains or reduces bone turnover in childbearing women, with effects varying by age and hormone combination. Moreover, bone-formation and reabsorption markers correlated positively to pro-androgenic progestins (p < 0.05). Thus, estrogen-progestogen combinations reduce bone turnover less when weak estrogens and a pro-androgenic or neutral progestin are present.

CONCLUSIONS

This study found that CHCs reduce bone turnover, with natural estrogens and androgenic progestins appearing to be more beneficial than EE and anti-androgenic types. These findings would potentially influence decisions relevant to CHC prescriptions during a woman's reproductive phases, emphasizing the need for additional research to tailor CHC usage to bone health.

Bone impact after two years of low-dose oral contraceptive use during adolescence

OBJECTIVE

Data regarding the use and effect of hormonal contraceptives on bone mass acquisition during adolescence are contradictory. The present study was designed to evaluate bone metabolism in two groups of healthy adolescents using combined oral contraceptives (COC).

METHODS

A total of 168 adolescents were recruited from 2014 to 2020 in a non-randomized clinical trial and divided into three groups. The COC1 group used 20 μg Ethinylestradiol (EE)/150 μg Desogestrel and the COC2 group used 30 μg EE/3 mg Drospirenone over a period of two years. These groups were compared to a control group of adolescent non-COC users. The adolescents were submitted to bone densitometry by dual-energy X-ray absorptiometry and measurement of bone biomarkers, bone alkaline phosphatase (BAP), and osteocalcin (OC) at baseline and 24 months after inclusion in the study. The three groups studied were compared at the different time points by ANOVA, followed by Bonferroni's multiple comparison test.

RESULTS

Incorporation of bone mass was greater in non-users at all sites analyzed (4.85 g in lumbar Bone mineral content (BMC)) when compared to adolescents of the COC1 and COC2 groups, with a respective increase of 2.15 g and loss of 0.43g in lumbar BMC (P = 0.001). When comparing subtotal BMC, the control increased 100.83 g, COC 1 increased 21.46 g, and COC 2 presented a reduction of 1.47 g (P = 0.005). The values of bone markers after 24 months are similar for BAP, being 30.51 U/L (± 11.6) for the control group, 34.95 U/L (± 10.8) for COC1, and 30.29 U/L for COC 2 (± 11.5) (P = 0.377). However, when we analyzed OC, we observed for control, COC 1, and COC 2 groups, respectively, 13.59 ng/mL (± 7.3), 6.44 ng/mL (± 4.6), and 9.48 ng/mL (± 5.9), with P = 0.003. Despite loss to follow-up occurring in the three groups, there were no significant differences between the variables in adolescents at baseline who remained in the study during the 24-month follow-up and those who were excluded or lost to follow-up.

CONCLUSION

Bone mass acquisition was compromised in healthy adolescents using combined hormonal contraceptives when compared to controls. This negative impact seems to be more pronounced in the group that used contraceptives containing 30 μg EE.

CLINICAL TRIAL REGISTRATION

http://www.ensaiosclinicos.gov.br, RBR-5h9b3c. "Low-dose combined oral contraceptive use is associated with lower bone mass in adolescents".

The Impact of Progesterone and Estrogen on the Tooth Mobility

Background and Objectives: Progesterone and estrogen modify the bone metabolism directly related to the periodontium, this study aimed at answering the question whether fluctuations in the levels of these hormones or the use of their synthetic equivalents in modern contraceptives have a significant impact on the natural tooth mobility (TM) in its alveolus. Materials and Methods: Sixty healthy women who had never been pregnant and when interviewed reported either (1) having regular menstruations every 28-30 days or (2) taking oral two-phase two-ingredient hormonal contraceptives formed, respectively, groups M and S in the study. TM evaluated as the Periotest value (PTV) was checked in the menstruation, ovulation, and luteal phases of the menstrual cycle (group M) and on the days corresponding to the moment of the menstrual cycle in group S. Results: Although the PTV-s were within the limits of norm, the canines and the molars were always more stable than the other teeth. In group M, the TM was statistically comparable (p > 0.05) in the menstrual and ovulation phases, thus significantly increased (p < 0.001) in the luteal phase. The TM remained constant (p = 0.758) in all studies in group S. The results demonstrated that the canines and the molars in the luteal phase were significantly more mobile in group M than in group S (p < 0.001), although increased mobility of the teeth in group M affected the canines and the first molars to a significantly lesser degree than the other teeth. Conclusions: However, since women between 20 and 30 years old constitute the majority of ortho-dontic patients, possible determination of the optimum moment of force application in relation to the sex hormones cycle, namely, to its luteal phase, is clinically very promising.

Bone health and hormonal contraception

INTRODUCTION

Short-term and long-term steroid contraceptive systems are widely employed in adolescents and premenopausal women; they could induce variation in bone metabolism, but whether these changes increase the overall fracture risk is not yet clear.

EVIDENCE ACQUISITION

A systematic search of scientific publications about "hormonal contraceptives" and "bone metabolism" in reproductive age women was conducted.

EVIDENCE SYNTHESIS

In adolescent girl, combined oral contraceptives could have a deleterious effect on bone health when their onset is within three years after menarche and when they contain ethinyl estradiol at the dose of 20 mcg. In perimenopausal women, steroid contraceptives seem not influence bone health nor increase osteoporotic fractures risk in menopause. The oral progestogens intake is not related to negative effects on skeletal health. Depot medroxyprogesterone acetate (DMPA) induce a prolonged hypoestrogenism with secondary detrimental effect on healthy bone; the higher bone loss was observed at the DMPA dose of 150 mg intramuscular such as after long-term DMPA-users. Progestin-based implants and intrauterine devices have not negative effect on bone health.

CONCLUSIONS

Since sex-steroid drugs induce variations in hormonal circulating concentrations, they may negatively affect bone metabolism. Contraceptive choice should be tailored evaluating any possible effect on bone health. Clinicians should always perform a precontraceptive counselling to identify any coexisting condition that may affect bone health. Further randomized studies are needed to confirm these results.

Effect of Extended 30 μg Ethinyl Estradiol with Continuous Low-Dose Ethinyl Estradiol and Cyclic 20 μg Ethinyl Estradiol Oral Contraception on Adolescent Bone Density: A Randomized Trial

STUDY OBJECTIVE

To compare changes in lumbar spine bone mineral density after 12 months of a 91-day extended regimen or 28-day combined oral contraceptive with those in a healthy reference group not using hormonal contraceptives.

DESIGN

Phase 2, multicenter, open-label, randomized, controlled study.

SETTING

Forty-five academic centers, clinical research centers, and community practices in the United States.

PARTICIPANTS

Eight hundred twenty-nine postmenarcheal adolescent girls aged 12-18 years.

INTERVENTIONS

Adolescents were randomly assigned to 91-day levonorgestrel (LNG)/ethinyl estradiol (EE) extended regimen (84 days of LNG 150 μg/EE 30 μg with 7 days of EE 10 μg [LNG/EE extended regimen]) or 28 days of LNG/EE (21 days of LNG 100 μg/EE 20 μg with 7 days of placebo [LNG/EE 21/7]) for 12 months. A reference group not seeking hormonal contraception was also evaluated.

MAIN OUTCOME MEASURES

The primary end point was mean percent change in lumbar spine bone mineral density measured using dual-energy x-ray absorptiometry.

RESULTS

Of 1361 adolescents randomized/enrolled, 829 were included in the primary analysis. Mean changes in lumbar spine bone mineral density were +2.26% with LNG/EE extended regimen, +1.45% with LNG/EE 21/7, and +2.50% in the reference group. Noninferiority of the LNG/EE extended regimen compared with the reference group was shown. A statistically significant treatment difference was found between LNG/EE 21/7 and the reference group (1.05%; 95% confidence interval, 0.61%-1.49%) but not between LNG/EE extended regimen and the reference group (0.23%; 95% confidence interval, -0.20% to 0.67%). No new safety signals were noted.

CONCLUSION

Compared with the reference group, bone accrual was statistically significantly lower among LNG/EE 21/7 users but not among LNG/EE 30-μg extended regimen users. Additional research is needed to clarify the clinical relevance of these findings.

Review: Contraception in adolescents with systemic lupus erythematosus

In the management of adolescents with systemic lupus erythematosus (SLE), sexual activity and prevention of unwanted pregnancies are important topics. Many contraceptive methods are available nowadays. Oral contraceptives (OCs) are the preferred choice among adolescents in general. However, the use of these medications in adolescents with SLE raises serious concerns, particularly the risk of thrombotic events from estrogen exposure and the impact of these medications on lupus activity. In this article, different contraceptive methods available are reviewed and their application in adolescents with SLE is discussed. In conclusion, OCs are the methods of choice in adolescents with stable disease and no antiphospholipid antibodies (aPL) detected. In patients with aPL, fewer options are available, and the selection of the preferred form of contraception should be made on an individual basis. Lupus (2007) 16, 600—605.

The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations

Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge. The best evidence (grade A) is available for positive effects of calcium intake and physical activity, especially during the late childhood and peripubertal years-a critical period for bone accretion. Good evidence is also available for a role of vitamin D and dairy consumption and a detriment of DMPA injections. However, more rigorous trial data on many other lifestyle choices are needed and this need is outlined in our research agenda. Implementation strategies for lifestyle modifications to promote development of peak bone mass and strength within one's genetic potential require a multisectored (i.e., family, schools, healthcare systems) approach.

The associations of exposure to combined hormonal contraceptive use on bone mineral content and areal bone mineral density accrual from adolescence to young adulthood: A longitudinal study

Background

The association of long term combined hormone based contraceptives (CHC) use on bone mineral content (BMC) and areal bone mineral density (aBMD) development remains controversial, as it appears that the relationship may be age-dependent. The purpose of this study was to investigate the long-term associations of CHC exposure on the accrual of bone parameters from adolescence into young-adulthood.

Methods

110 women (67 exposed to CHC) were drawn from the Pediatric Bone Mineral Accrual Study (PBMAS). Serial measures of total body (TB), lumbar spine (LS) and femoral neck (FN) BMC and aBMD were assessed by DXA (a total of 950 scans) and aligned by biological age (BA, years from peak height velocity [PHV]). Multilevel random effects models were constructed to assess the time dependent associations between annual CHC exposure and the development of bone parameters.

Results

After BA, height, lean tissue mass, fat mass, calcium and vitamin D intake, and physical activity were controlled, it was observed that those individuals exposed to CHC 6-years post PHV developed significantly less (−0.00986 ± 0.00422 g/cm²) TB aBMD than their non CHC exposed peers. Additionally, there were significant BA by CHC exposure interactions, where CHC exposure 6-years or more post PHV resulted in developing less TB BMC (−4.94 ± 2.41 g), LS BMC (−0.29 ± 0.11 g) and LS aBMD (−0.00307 ± 0.00109 g/cm²). One year after the attainment of PHV, CHC users were predicted to have 1.2% more TB BMC, 3.8% more LS BMC and 1.7% more LS aBMD than non-users. At 9-years post PHV the predicted differences showed that CHC users had 0.9% less TB BMC and 2.7% less LS BMC and 1.6% less LS BMD than those not exposed to CHC.

Conclusions

CHC may not hinder the development of BMC or aBMD during adolescence; however, exposure 6-years or more after PHV may be detrimental.

•

The effects of combined hormone contraceptive (CHC) exposure on bone mass were assessed.

•

CHC exposure resulted in developing significantly less (− 9.86 ± 4.22 g/cm²) TB aBMD.

•

CHC exposure 6-years after PHV resulted in significantly less BMC and aBMD.

•

CHC may not hinder adolescent bone development, but may be detrimental after growth.

Combined oral contraceptives' influence on weight, body composition, height, and bone mineral density in girls younger than 18 years: a systematic review

OBJECTIVE

Combined oral contraceptives (COCs) are increasingly used by adolescents. The aim of this review is to investigate the evidence regarding COCs' influence on weight, height and bone mineral density (BMD) in girls younger than 18 years.

METHOD

Systematic literature search using PubMed/Medline and Scopus (January 1990-February 2012) on COCs for girls under 18 years of age and the possible influence on body parameters. MeSH terms: Oral contraception; Adolescent; Weight; Body composition; Height; Bone mineral density.

RESULTS

There is no evidence that COCs induce weight gain in girls younger than 18 years. Obese girls are not at higher risk of gaining weight. COCs do not cause changes in body fat and lean mass beyond the changes caused by natural development. Moreover, growth and stature are unaffected. Few studies indicate that COCs have a negative impact on BMD, but the evidence is presently too limited for definite conclusions.

CONCLUSION

Studies in young users are few. Presently, there are no indications of a negative impact of COCs on weight, body composition or height. Lesser increases in BMD cannot be excluded. As the demand for COCs is increasing among the youngest girls, there is a need for prospective studies addressing this issue.

Low-dose estrogen combined oral contraceptives may negatively influence physiological bone mineral density acquisition during adolescence

BACKGROUND

The aim was to evaluate changes of bone mineral density (BMD) and markers of bone turnover in healthy adolescents, and in adolescent users of combined oral contraceptives (COCs) with different ethinylestradiol (EE) contents.

METHODS

In this prospective crossover study, 56 healthy females (15-19.5 years) with desire to use hormonal contraception were randomized to COC with either 30 or 15 μg of EE in crossover design of 9-month intervention each in reverse order. Nonusers of the same age (n=28) served as controls. BMD at lumbar spine (LS), total femur, femoral neck, distal radius, and total body, and serum markers (N-propeptide of type I procollagen, and type I collagen C-telopeptide) were measured at baseline and after 9 and 18 months.

RESULTS

In COC nonusers, BMD significantly increased at LS and radius, while markers decreased. In COC users, BMD did not increase, with the exception of LS BMD in the 30 μg COC group (P<0.05). In the crossover design, a difference between the low- and very low-dose COC users was found in LS BMD changes (P<0.05), where increase in BMD was more impaired in the 15 μg COC users. The skeletal effects of COC remained significant after adjustments for age and smoking status. Markers declined faster in COC users during the first period, while they remained stable or even increased during the second 9 months.

CONCLUSION

Physiological acquisition of LS BMD during adolescent age may be prevented by use of COC, especially those containing very low dose of EE.

The effect of hormonal oral contraception on acquisition of peak bone mineral density of adolescents and young women

Maximizing bone mass in youth is touted as the best strategy to offset the natural losses of aging and the menopausal transition. Not achieving maximum peak bone mineral density (BMD) is an independent risk factor for osteoporosis and thus a public health concern. Adolescence is a critical time of bone mineralization mediated by endogenous estradiol. Research has shown that the highest velocity of bone mass accrual occurs 1 year before menarche and after the first 3 years. Low-peak attainment of BMD in young women is associated with contributing factors such as diets low in calcium, eating disorders, lack of exercise, smoking, and low estrogen states. Oral contraceptives (OCs) suppress endogenous estradiol production by suppressing the hypothalamic-pituitary-ovarian axis. Thus, OCs, by replacing endogenous estradiol with ethinyl estradiol (EE), establish and maintain new hormone levels. The early initiation and the use of very low dose of EE raises the possibility that bone mass accrual at a critical time of bone mineralization in young women or adolescents may be jeopardized. This review examines the studies of BMD in adolescents and young women that use combination hormonal contraception. Some studies had inherent limitations, such as small trial, poor control of confounders, failure to exclude women with prior use of hormonal contraceptives, or prior pregnancy from control groups. The vast majority of reviewed studies showed OCs containing 20 to 30 µg of EE interfere with acquisition of peak BMD. Limited numbers of studies examine the effects of OCs containing 35 µg on adolescents and young adults. Additionally, studies are needed evaluating the progestin component of OCs as their differing androgenic properties may affect bone mineralization as well.

Novel actions of progesterone: what we know today and what will be the scenario in the future?

Objectives

This article is aimed to review the novel actions of progesterone, which otherwise is considered as a female reproductive hormone. The article focuses on its important physiological actions in males too and gives an overview of its novel perspectives in disorders of central and peripheral nervous system.

Key findings

Progesterone may have a potential benefit in treatment of traumatic brain injury, various neurological disorders and male related diseases like benign prostatic hypertrophy (BPH), prostate cancer and osteoporosis. Norethisterone (NETA), a progesterone derivative, decreases bone mineral loss in male castrated mice suggesting its role in osteoporosis. In the future, progesterone may find use as a male contraceptive too, but still needs confirmatory trials for safety, tolerability and acceptability. Megestrol acetate, a progesterone derivative is preferred in prostatic cancer. Further, it may find utility in nicotine addiction, traumatic brain injury (recently entered Phase III trial) and Alzheimer's disease, diabetic neuropathy and crush injuries. Studies also suggest role of progesterone in stroke, for which further clinical trials are needed. The non genomic actions of progesterone may be in part responsible for these novel actions.

Summary

Although progesterone has shown promising role in various non-hormonal benefits, further clinical studies are needed to prove its usefulness in conditions like stroke, traumatic brain injury, neuropathy and crush injury. In male related illnesses like BPH and prostatic Ca, it may prove a boon in near future. New era of hormonal male contraception may be initiated by use of progesterone along with testosterone.

Oral contraceptive use and bone mass in women aged 26-36 years

INTRODUCTION

The association between hormonal contraceptive use and bone mineral density remains controversial.

HYPOTHESIS

Hormonal contraceptive use is positively associated with bone mass in young premenopausal women.

METHODS

Cross-sectional analysis of data collected from women aged 26-36 years (n = 687) in the Childhood Determinants of Adult Health study-a longitudinal study investigating childhood determinants of cardiovascular disease, diabetes, and other chronic diseases in adulthood. Participants were not currently pregnant or breast-feeding. Contraceptive use was obtained by self-administered questionnaire. Women were categorized as combined oral contraceptive users (n = 219), progestogen-only contraceptive users (n = 43), and non-users of hormonal contraceptives (n = 425). Bone mass was measured by quantitative ultrasound.

RESULTS

Compared with women who were not using any hormonal contraceptives, women using combined oral contraceptives had significantly higher values of broadband ultrasound attenuation (BUA), speed of sound, and quantitative ultrasound index. These associations remained after adjustment for confounders. Progestogen-only contraceptive users had higher BUA than non-users, but the differences were not statistically significant in this small group.

CONCLUSION

Combined oral contraceptive use was associated with higher bone mass measured by quantitative ultrasound in this population-based sample of premenopausal women aged 26-36 while progestogen-only contraceptives appeared to have no deleterious effect on bone mass.

Effects of lifestyle and diet on bone health in young adult Chinese women living in Hong Kong and Beijing

BACKGROUND

Dietary and lifestyle variations may be too small to detect possible associations with bone mineral density (BMD) within a community. Pooled data from communities with different diets and lifestyle but of the same ethnicity may help explore these associations.

OBJECTIVE

To examine the effects of dietary and lifestyle factors on BMD in young Chinese women.

METHODS

Baseline data were analyzed from 441 women aged 20 to 35 years in Hong Kong and Beijing who were participating in a longitudinal study evaluating the effect of milk supplementation on bone health. Data on demographic characteristics, lifestyle, use of oral contraceptives, diet, physical activity, and BMD of total hip, femoral neck, and total spine measured by dual-energy x-ray absorptiometry were pooled for analysis.

RESULTS

Hong Kong subjects had significantly lower BMD and higher body-size-adjusted dietary intakes of protein, fat, fiber, vitamins, potassium, sodium, and selenium than Beijing subjects. Multivariate regression of pooled data showed that body mass index was the most important determinant of BMD at all sites. Age was negatively associated and use of oral contraceptives was positively associated with femoral neck BMD. Carbohydrate intake was positively associated with total hip BMD. Fiber intake was negatively associated with BMD at total hip and total spine. Increased vitamin E intake was associated with greater total spine BMD. None of the nutrients were associated with BMD at the femoral neck.

CONCLUSIONS

Diet, lifestyle, and BMD differed greatly between young women from Hong Kong and Beijing. Body mass index was the most important determinant of BMD in young Chinese women, whereas age, use of oral contraceptives, and diet had less pronounced effects.

Oral contraceptive use and bone density in adolescent and young adult women

BACKGROUND

Most of the millions of oral contraceptive (OC) users are under 30 years of age and in the critical period for bone mass accrual.

STUDY DESIGN

This cross-sectional study of 606 women aged 14-30 years examined both OC duration and estrogen dose and their association with bone mineral density (BMD) at the hip, spine, and whole body (dual-energy X-ray absorptiometry).

RESULTS

Of 389 OC users and 217 nonusers enrolled, 50% were adolescents (14-18 years). Of OC users, 38% used "low-dose" OCs [<30 mcg ethinyl estradiol (EE)]. In adolescents, mean BMD differed by neither OC duration nor EE dose. However, 19- to 30-year-old women's mean BMD was lower with longer OC use for spine and whole body (p=.004 and p=.02, respectively) and lowest for >12 months of low-dose OCs for the hip, spine and whole body (p=.02, .003 and .002, respectively).

CONCLUSIONS

Prolonged use of today's OCs, particularly <30 mcg EE, may adversely impact young adult women's bone density while using these agents.

Fracture risk in very young women using combined oral contraceptives

BACKGROUND

Little is known on fracture risk in young women using oral contraceptives.

STUDY DESIGN

Case-control study (64,548 cases, 193,641 controls).

RESULTS

Overall, no major association with risk of fracture was present. Only in a few age groups a limited increase (OR 1.1-1.5) was seen in those using low average doses (less than one tablet per day - i.e., intermittent use). Neither 20 nor >or=30 mcg per day of ethinylestradiol was associated with risk of fractures, while changing from 20 to >or=30 mcg per day or vice versa was associated with a limited increase in fracture risk (OR 1.1-1.4) in some age groups.

CONCLUSIONS

In general, use of oral contraceptives in young women did not seem to be associated with an increased risk of fractures. The isolated increase seen in some strata with low average doses may be linked to factors associated with discontinuation of oral contraceptives rather than pharmacological effects.

Multigenerational exposure to ethinyl estradiol affects bone geometry, but not bone mineral density in rats

Estrogenic compounds are known to prevent bone loss in ovariectomized adult rats; however, their effects on bone in developing and reproductively-intact rats are less well-understood. In a large multigenerational experiment 0, 2, 10, or 50 ppb ethinyl estradiol (EE) in the diet was fed to intact male and female rats from conception until either weaning, postnatal day 140, or continuously for 2 years. Vertebrae (lumbar and caudal) and femurs were collected from subsets of these animals at necropsy at 48 days, 70 days, 140 days, or 2 years of age and subjected to dual-energy X-ray absorptiometry (DXA) scanning to measure bone mineral density (BMD), bone mineral content (BMC), and bone area. In addition, the length, cross-sectional area, marrow area, and cortical bone area of the femurs were measured directly in all animals at PND 140 and 2 years. Continuous dietary intake of 50 ppb EE decreased body weight by 8-27%. BMD adjusted for body weight was not affected by EE, with the exception of an increase in the caudal vertebrae in males treated with 50 ppb EE. In female rats, continuous treatment with 50 ppb EE decreased length and cross-sectional area of the femur. The length of the femur was decreased in the first two generations following institution of a phytoestrogen-free diet at the initiation of the study in all animals, including controls, but returned to the original length by the third or fourth generation. The cross-sectional area of the femur also varied by generation. In conclusion, a high dose of EE throughout the lifespan resulted in decreased bone size in females, which could reduce the force required to break the bone. Furthermore, dietary changes may have epigenetic effects which persist for multiple generations.

Estrogen-progestin contraceptive use during adolescence prevents bone mass acquisition: a 4-year follow-up study

BACKGROUND

Estrogen-progestin contraception may affect estrogen production and alter the development of peak bone mass.

STUDY DESIGN

A 4-year follow-up with 122 adolescent women aged 12-19 years. The data were divided into three groups based on estrogen-progestin contraceptive (EPC) use: (i) nonusers (n=52), (ii) 1-2 years of use (n=24) and (iii) use for more than 2 years (n=46). The estrogen dose of the preparations was < or =35 mcg. Height, weight, and the amount of exercise (ratio of work metabolic rate, h/week) as well as bone mineral content (BMC) of lumbar spine and femoral neck were measured repeatedly.

RESULTS

There was a significant trend showing less of an increase in the mean adjusted BMC of lumbar spine in the group of adolescent women who had used EPC for more than 2 years compared with the two other groups. In the mean adjusted BMC of the femoral neck, there was a significant trend of a smaller increase in EPC users for more than 2 years compared with 1-2 years of use.

CONCLUSIONS

Long-term EPC with low-dose estrogen preparations seems to suppress normal bone mineral accrual in adolescent women.

A qualitative analysis of accounts of hormonal contraceptive use: experiences and beliefs of British adolescents

OBJECTIVES

Britain has high rates of unintended adolescent pregnancy compared to other European countries. Relatively little is known about the beliefs, attitudes and experiences of using hormonal contraceptive methods amongst middle-class adolescents, and mention of their views in the literature will add to the knowledge in this area. The current qualitative study addresses these issues to some extent.

METHODS

Middle-class 16-18-year-old men and women were interviewed about their understanding and use of hormonal contraceptives. The interviews were transcribed verbatim and transcripts subjected to an adaptation of interpretative phenomenological analysis (IPA).

RESULTS

Six emergent themes represent important aspects of these adolescents' experiences: negative experiences, experiences unrelated to pregnancy prevention, mistrust of the pill, risk reduction, issues of communication and trust, and perceptions of pill promotion by adults.

CONCLUSIONS

The findings illustrate the complexities inherent in contraceptive health care in relation to hormonal methods and highlight not only potential targets for enhancing effective use, but the importance of the way such information is disseminated.

La contraception des adolescentes en France en 2007

The two main objectives of adolescence contraception are the eviction of involuntary pregnancies and the prevention of sexually transmitted infections. In France, in spite of our rich contraceptive arsenal and a widely spread information, the rate of voluntary termination of pregnancy keeps growing among the teenagers population--and this, probably because the gap between theoretical effectiveness and practice of contraception is particularly wide among the young people. Every contraceptive means can be used by teenagers; the best option being, it seems, the "double DUTCH", which consists of concomitant use of condoms and hormonal contraception. Most often, the consultation for contraception is the first gynaecological consultation. That is the reason why it is usually stressful for teenagers who dread undergoing a gynaecological examination. If this examination is not necessary for most of young patients, it is essential to create a trustful relationship and to make explicit the several contraceptive methods. During this consultation it is interesting to look for common teenage troubles like addiction to smoking and eating disorders. For any prescription of hormonal contraception, it is important to explain the benefits and the possible side effects, to stress the observance and to tell the teenager about the recommendations in case of forgetting. Concerning condom - the only efficient way of preventing sexually transmitted infections--, it is useful to talk about it in concrete and straightforward terms, to show its handling and to inform about risks of tearing. With this state of mind, an emergency contraception can be prescribed straightaway in order to make its use easier. Also, without any moralizing speech, the need for maturity must be emphasized as well as taking care of one's body with the aim of avoiding a premature pregnancy or any sexually transmitted infection. This consultation must be coupled with a close follow-up, availability and mutual confidence which are the main elements vouching for a good observance and consequently an efficient contraception.

The influence of lifestyle, menstrual function and oral contraceptive use on bone mass and size in female military cadets

Purpose

To 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.

Methods

Menstrual 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).

Results

The 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.

Conclusion

In 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.

Hormonal contraception in adolescents: special considerations

With the rates of unintended pregnancies in teenagers remaining high, it is crucial to present adolescents with all of the contraceptive options available to them. While barrier methods, for example, male condoms, are easily accessible and do not have adverse effects, their use must be consistent and correct with each act of intercourse. Hormonal contraception affords much better efficacy in preventing pregnancy when used with full compliance. Oral contraceptives are a popular method of contraception among adolescents and offer many non-contraceptive benefits along with the prevention of pregnancy. They have very few significant adverse effects, which are outweighed by the significant morbidity associated with teenage pregnancies, and can be used by most adolescent females. However, their minor bothersome effects do contribute to the high discontinuation rates seen. In addition, many girls find it difficult to remember to take a pill every day, leading to higher failure rates in teenagers than in adult women. The advent of long-acting, progestogen (progestin)-only methods, such as injectables and implantables, has been generally accepted by adolescents and these methods have proven to be more efficacious by avoiding the need for daily compliance. However, progestogen-only methods cause irregular bleeding and amenorrhea, which is not acceptable to many teenagers. In addition, the most widely used implant was taken off the market a few years ago and newer forms are not yet widely accessible. Other novel methods are currently available, including the transdermal patch and the vaginal ring. Both are combinations of estrogen and progestogen and have similar efficacy and adverse effect profiles to oral contraceptives. Their use may be associated with greater compliance by adolescents because they also do not require adherence to a daily regimen. However, there may be some drawbacks with these newer methods, for example, visibility of the patch and difficulty with insertion of the vaginal ring. When regular contraceptive modalities fail, emergency contraception is available. Choices include combination oral contraceptives, progestogen-only pills, mifepristone, or placement of a copper-releasing intrauterine device. These methods can be very useful for preventing pregnancy in adolescents as long as adolescents are aware of their existence and have easy access to them.

Determinants of skeletal loss and recovery in anorexia nervosa

CONTEXT

Anorexia nervosa (AN) is complicated by severe bone loss. The effects of persistent undernutrition and consequent neuroendocrine dysfunction on bone mass and the factors influencing skeletal recovery have not been well characterized.

OBJECTIVE

The objective of the study was to determine the rate of bone loss at the spine and hip in women with AN and whether resumption of menstrual function and/or improvement in weight are determinants of skeletal recovery in AN.

DESIGN

The study had a longitudinal design.

SETTING

The study was conducted at a clinical research center.

STUDY PARTICIPANTS

Participants included 75 ambulatory women with AN.

MAIN OUTCOME MEASURES

Bone mineral density (BMD) and body composition were measured with dual x-ray absorptiometry.

RESULTS

In women not receiving oral contraceptives, those who did not improve weight or resume menses had a mean annual rate of decline of 2.6% at the spine and 2.4% at the hip. Those who resumed menses and improved weight had a mean annual increase of 3.1% at the posteroanterior spine and 1.8% at the hip. Women who recovered menses demonstrated a mean increase of posteroanterior spine but not hip BMD, independent of weight gain. Women who improved weight, regardless of whether they recovered menstrual function, demonstrated a mean increase of hip, but not spine, BMD. Increase in fat-free mass was a more significant determinant of increased BMD than weight or fat mass gain. In women receiving oral contraceptives, there was no increase in BMD at any site despite a mean 11.7% weight increase.

CONCLUSIONS

These data suggest that rapid bone loss, at an average annual rate of about 2.5%, occurs in young women with active AN. Resumption of menstrual function is important for spine BMD recovery, whereas weight gain is critical for hip BMD recovery. We did not observe an increase in BMD with weight gain in women receiving oral contraceptives. Therefore, improvements in reproduction function and weight, with increases in lean body mass a critical component, are both necessary for skeletal recovery in women with AN.

Combined hormonal contraception and bone health: a systematic review

This systematic review examined whether women who use combined hormonal contraception experience changes in risk of fracture or bone mineral density (BMD) that differ from nonusers. We identified 86 articles from PubMed and EMBASE (published 1966 to August 2005) that reported on fracture or BMD outcomes by use of combined hormonal contraceptives. The evidence relating to combined oral contraceptives (COCs) and fracture is inconclusive, as results from the available studies conflict. Studies of adolescent and young adult women generally found lower BMD among COC users than nonusers. Evidence for premenopausal adult women suggested no differences in BMD between COC users and nonusers. COC use in perimenopausal and postmenopausal women preserved bone mass, while nonusers lost BMD, but BMD among former COC users in this age group was the same as for never-users. Evidence for other combined hormonal methods was very limited, with one study indicating no effect of combined hormonal injectable use among premenopausal women on BMD and one study suggesting lower BMD among premenopausal users of the NuvaRing than in nonusers.

Effect of oral contraceptives and hormone replacement therapy on bone mineral density in premenopausal and perimenopausal women: a systematic review

Seventy five articles on the effect of oral contraceptives and other hormone replacement on bone density in premenopausal and perimenopausal women were reviewed. The evidence was appraised using the Oxford Centre for Evidence-Based Medicine levels of evidence. There is good evidence for a positive effect of oral contraceptives on bone density in perimenopausal women, and fair evidence for a positive effect in "hypothalamic" oligo/amenorrhoeic premenopausal women. There is limited evidence for a positive effect in healthy and anorexic premenopausal women. In hypothalamic oligo/amenorrhoeic women, baseline bone density has been shown to be significantly lower than that in healthy controls, therefore the decision to treat is clinically more important. The ideal formulation(s) and duration of treatment remain to be determined by further longitudinal and prospective randomised controlled trials in larger subject populations.

Prior oral contraception and postmenopausal fracture: a Women's Health Initiative observational cohort study

OBJECTIVE

To test for the possible association of past oral contraceptive (OC) use and incident fracture after menopause.

DESIGN

A prospective cohort of 93,725 postmenopausal women.

SETTING

Forty Women's Health Initiative (WHI) clinical centers across the United States.

PATIENT(S)

Ethnically diverse 93,725 volunteer postmenopausal women, 50 to 79 years old.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The main outcome was self-reported incident first fracture assessed prospectively by annual questionnaire.

RESULT(S)

The adjusted relative hazard (HR) for fracture among past OC users was 1.07 (95% CI, 1.01-1.15). Among women without any postmenopausal hormone treatment, past OC use for < or =5 years led to an HR of 1.15 (95% CI, 1.04-1.27) and for past OC use >5 years led to an HR of 1.09 (95% CI, 0.97-1.23) compared with never users.

CONCLUSION(S)

This study does not support the idea that past OC use protects against later fracture.

Oral contraceptive use in young women is associated with lower bone mineral density than that of controls

Osteoporosis is a skeletal disease affecting 44 million Americans. A primary strategy to prevent osteoporosis is to develop a high peak bone mass in youth. Oral contraceptives (OCs) alter hormones in women and could affect bone mass development. Fifty percent of American women between the ages of 20 and 24 years use OCs. However, the interaction between OCs and skeletal mineralization is poorly understood. Our aim was to compare bone mass [bone mineral density (BMD)] of young women who had a history of OC use, with regularly menstruating controls. We recruited 98 women who were 18 to 25 years of age and had a history of OC use (n=44, 3.4+/-1.9 years of OC use) and controls (n=58). BMD at the hip, whole-body, and spine [anterior-posterior (AP) and lateral grams per square centimeter] was measured by dual-energy X-ray absorptiometry (DXA). Physical activity [in metabolic equivalents (METs)] was measured via questionnaire, and grip strength was evaluated with an isometric dynamometer. Groups were similar in body mass index (BMI), fat mass, grip strength, calcium intake and physical activity, but OC users were slightly older than controls (21.3+/-1.9 years vs 20.3+/-1.6 years, P<0.05). In analysis of covariance, controlled for age and BMI, controls had significantly greater BMD than OC users at the AP and lateral spine, femoral neck, greater trochanter, total hip, and whole body (P<0.05). We conclude that, in this cross-sectional analysis, oral contraceptive use by young women may compromise bone health during a time when mineral is still accruing.

[Adolescent contraception. Current trends]

Despite easy availability of contraception, Germany is confronted with the problem of increasing rates of pregnancies and abortions in minors. Prescription of contraceptives that do not rely on compliance and are acceptable to adolescents is required in addition to improved counseling. For that purpose, adherence to the guidelines for the use of contraceptives in minors written by the consortium for legislation in medicine (AG Medizinrecht) is essential. Oral contraceptives are the most commonly prescribed form of birth control, advantages include reversibility as well as a good tolerance and safety profile. New developments are low-dose compounds, novel progestins, prevention of ovulation by pure gestagen pills and the long-term use of low-dose monophasic micro pills. Long-term contraceptives like subdermally implantable depot compounds or hormone-releasing pessaries in utero have been used on a regular basis and seem a convenient alternative for birth control for longer periods, also in adolescents. The easy-to-use intravaginal ring and the birth control patch have expanded the spectrum of hormone-releasing contraceptive systems. Studies show improved compliance and a possible reduction of unintentional pregnancies due to application errors. Amelioration of the range of highly effective birth control products different modes of application will hopefully lead to drop in the rate of unplanned pregnancies, especially in adolescents.

Effect of oral contraceptive treatment on bone mass acquisition in skeletally immature young female rats

The objective of the present study was to investigate the effect of oral contraceptive (OC) treatment on bone mass accrual in skeletally immature young female rats. Animals in the baseline group were killed at the beginning of the experiment and were subjected to bone density assessment by peripheral quantitative computerized tomography (pQCT). The control group was fed a base diet free of phytoestrogens, while animals in the contraceptive group received the same base diet mixed with 2.67 microg desogestrel/100 g body weight and 0.0533 microg ethinyl estradiol/100 g body weight. The duration of the treatment period was 16 weeks. Densitometric measurements by dual energy x-ray absorptiometry and serum bone markers assessment were carried out at baseline, at 8 weeks and at 16 weeks, while pQCT densitometry took place after sacrifice. All bone mineral density and bone mineral content indices measured by dual energy x-ray absorptiometry increased significantly throughout the study period in both the OC and control group. Concerning pQCT measurements, animals in both the OC and the control group had significantly higher cortical density compared with baseline (midtibia: p=.0003 and .0003, respectively). Total area and periosteal circumference were significantly higher in OC group, both in proximal (p=.003 and .003, respectively) and midtibia (p=.048 and .042, respectively) compared with baseline. Osteoprotegerin serum levels increased in both groups, and at the end of the experiment, circulating osteoprotegerin was significantly higher in the OC group compared with controls (p=.032). At the end of the experiment, carboxyl-terminal telopeptides of collagen type I levels were significantly lower in the OC-treated animals compared with controls (p=.046). Our results suggest that OC administration to skeletally immature female rats allows normal bone accrual and may even improve bone geometry. This effect may be mediated through enhanced inhibition of bone resorption.

Depot medroxyprogesterone acetate, oral contraceptives and bone mineral density in a cohort of adolescent girls

PURPOSE

To conduct a longitudinal comparison of bone mineral density (BMD) in 370 adolescent girls, aged 12-18, who self-selected depot medroxyprogesterone acetate (DMPA) or an oral contraceptive (OC) containing 20 microg ethinyl estradiol/100 microg levonorgestrel with that in girls who received no hormonal treatment (control group).

METHODS

Lumbar spine and femoral neck BMD measurements were obtained by dual energy x-ray absorptiometry at baseline and 12 months. Data were analyzed with repeated measures analysis of covariance methods.

RESULTS

Over 12 months, lumbar spine BMD decreased in the DMPA group (n = 29), with a mean percent change of -1.4% (95% confidence interval [CI] -2.73, -0.10), and increased by a mean of 3.8% (95% CI 3.11, 4.57) in the control group [n = 107 (p < .001)]. The increase in mean percent change in lumbar spine BMD in the OC group (n = 79), 2.3% (95% CI 1.49, 3.18), was significantly smaller than in the control group (p = .03). Over 12 months, the mean percent change in femoral neck BMD was -2.2% (95% CI -3.95, -0.39) in the DMPA group, but increased 2.3% (95% CI 1.29, 3.27) in the control group (p < .001). The increase in mean percent change at the femoral neck in the OC group, 0.3% (95% CI -0.87, 1.41), was significantly lower than in the control group (p = .03).

CONCLUSIONS

Our study contributes to an increasing body of knowledge indicating a negative impact of DMPA on bone health in young women. Additional findings suggest a potential adverse effect of an OC containing 20 microg ethinyl estradiol/100 microg levonorgestrel on bone health in adolescents.

Lifestyle influences on 9-year changes in BMD in young women

The effects of dietary calcium intake and physical activity on longitudinal changes in BMD over a mean of 9.4 years were examined in 62 healthy young women. Proximal femur BMD declined, lumbar spine BMD increased, and physical activity was associated with BMD change at intertrochanter and total hip sites.

INTRODUCTION

Maximizing premenopausal BMD is an important strategy for the prevention of osteoporosis and resultant fractures later in life.

MATERIALS AND METHODS

Young women who previously participated in a placebo-controlled 2-year calcium intervention study at a mean age of 18.5 +/- 0.3 years were remeasured at 27.8 +/- 1.0 years of age. DXA (Hologic QDR 1000W) was used to measure changes in BMD, and lifestyle factors were ascertained by questionnaire.

RESULTS AND CONCLUSIONS

Early decline in BMD at the neck of femur (-3.3%/decade) and the converse gain in BMD at the lumbar spine (+4.3%/decade) and intertrochanter (+1.9%/decade) suggest site-specific changes in BMD in young premenopausal women. No effect of previous calcium supplementation was seen on current BMD or changes in BMD (p > 0.10). Lifestyle predictors of change in BMD were determined using hierarchical regression analysis after forced correction for the covariates baseline BMD and previous calcium supplementation. Physical activity was positively associated with change in BMD at total hip and intertrochanter sites (beta-coefficients, beta = 0.26 and 0.26 respectively; p < 0.05). Calcium intake was negatively associated with change in BMD at the lumbar spine (beta = -0.27, p < 0.05). Parity was negatively associated with change in BMD at all sites (beta = -0.40 to -0.26, p < 0.05). These data show that BMD is already declining at the proximal femur in these healthy young women. Physical activity assists in maintenance of BMD at some sites and thus may contribute to lifelong fracture prevention. There was no positive association between calcium intake and change in BMD.

Effects of hormonal contraception on bone mineral density after 24 months of use

OBJECTIVE

To measure the effect of 24 months of depot medroxyprogesterone acetate use on bone mineral density compared with oral contraception (pills) and nonhormonal contraception.

METHODS

Women aged 18-33 years self-selected oral contraception, depot medroxyprogesterone acetate, or nonhormonal contraception (controls). Those selecting pills were randomized to formulations containing either 35 microg ethinyl estradiol and norethindrone or 30 microg ethinyl estradiol and desogestrel. Controls were frequency matched on age and race/ethnicity to hormonal contraception users. Dual-energy X-ray absorptiometry of the lumbar spine (L1-L4) was performed at baseline, 12 months, and 24 months. Percent change in bone mineral density was analyzed by using analysis of covariance, adjusting for age, race/ethnicity, weight-bearing exercise, calcium intake, smoking status, and body mass index.

RESULTS

Of the 191 women making up the final sample, 86 used pills, 47 used depot medroxyprogesterone acetate, and 58 used nonhormonal contraception. Women using depot medroxyprogesterone acetate for 24 months experienced, on average, a 5.7% loss in bone mineral density, with a 3.2% loss occurring between months 12 and 24. On average, users of desogestrel pills experienced a 2.6% loss in bone mineral density after 24 months. Bonferroni-adjusted pairwise comparisons demonstrated that bone mineral density changes from baseline to 24 months among depot medroxyprogesterone acetate users differed significantly from changes experienced by either of the pill groups or the control group. Changes in bone mineral density among users of either pill did not significantly differ from each other or from controls.

CONCLUSION

Loss of bone mineral density associated with depot medroxyprogesterone acetate use appears to be linear during the first 2 years of use. Shifts in bone mineral density among pill users were not significant when compared with controls.

Lifestyle factors and the development of bone mass and bone strength in young women

OBJECTIVE

To evaluate the contributions of adolescent calcium intake, oral contraceptive use, and exercise on bone mass and bone strength.Study design Eighty white women participated in 10 years of the Penn State Young Women's Health Study, a longitudinal study of community participants. We measured bone mineral mass (g), density (BMD, g/cm(2)), and body composition from dual energy x-ray absorptiometry and estimated proximal femur section modulus (bone bending strength). Calcium intake was determined from 45 days of prospective food records at regular intervals between the ages of 12 and 22 years. Exercise history and oral contraceptive use were assessed by questionnaire.

RESULTS

Daily calcium intakes between the ages of 12 and 22 years ranged from 500 to 1900 mg/d and were not significantly associated with bone gain or bone strength. Oral contraceptive use during adolescence was not correlated with bone or body composition measurements. Femoral neck BMD did not change from 17 to 22 years of age, but section modulus increased 3% (P <.05). Only exercise during adolescence was significantly associated with increased BMD and bone bending strength.

CONCLUSIONS

Adolescent lifestyle patterns can influence young adult bone strength. Our data suggest that exercise is the predominant lifestyle determinant of bone strength for this cohort.

A 3-year double-blind, randomized, controlled study on the influence of two oral contraceptives containing either 20 microg or 30 microg ethinylestradiol in combination with levonorgestrel on bone mineral density

In this first prospective, double-blind, randomized, parallel-group study we evaluated the influence of two combined oral contraceptives on bone mineral density (BMD) and metabolic bone parameters. One dose-reduced preparation contained 20 microg ethinylestradiol (EE) in combination with 100 microg levonorgestrel (LNG) (20/100) was compared with the reference preparation which contained 30 microg EE in combination with 150 microg LNG (30/150). Data from 48 volunteers aged 20-35 years were obtained over an observation period of 36 treatment cycles. The direction of the change (increase or decrease) in all investigated bone-related variables was similar in both treatment groups. As compared to baseline, bone mineral density decreased by 0.4% in the 20/100 group and by 0.8% in the 30/150 group after 36 treatment cycles. These changes were not significantly different between the two treatment groups (p = 0.902). For bone-specific alkaline phosphatase, we measured a mean increase of 55.4% (20/100 group) and of 113.2% (30/150 group) after 36 treatment cycles. The two treatments did not differ statistically significantly (p = 0.522). With respect to cross-linked N-telopeptides (NTx), we detected a decrease of the mean NTx urine concentrations of 21.1% (20/100) and of 13.4% (30/150). These changes also did not significantly differ between the two treatments (p = 0.613). Both study treatments were safe and well-tolerated by all volunteers participating in the study. In conclusion, BMD did not change during the 3-year observation period. Thus, both trial preparations containing either 20 or 30 microg EE in combination with LNG were capable of maintaining BMD in young fertile women. There is no reason to assume that the EE dose reduction had any negative impact on BMD. Because there were no differences in BMD between the treatment groups, it can be assumed that even lower dosages than 20 microg EE might be sufficient for bone protection. Biochemical markers provided evidence for a reduced bone resorption.

Bone mineral density in adolescent and young adult women on injectable or oral contraception

PURPOSE OF REVIEW

This report critically reviews recent original research articles that pertain to bone mineral density in young adult women utilizing injectable depot medroxyprogesterone acetate or oral contraceptives.

RECENT FINDINGS

Some evidence indicates that depot medroxyprogesterone acetate and ultra-low dose oral contraceptives (containing 20 microg ethinyl estradiol) may interfere with the large increases normally observed in adolescence; however, the same degree of bone loss (or lack of bone gain) associated with these drugs is not so impressive in young adult women who would typically be experiencing small changes in bone mass. Data obtained from young adult women show that low dose (30-40 microg ethinyl estradiol) oral contraceptives seem to be more protective of bone than ultra-low dose oral contraceptives. The few extant data suggest that there may be substantial increases in bone mass after discontinuation of depot medroxyprogesterone acetate; no information is available regarding the response of bone after discontinuation of oral contraceptives. As the clinical risk for fracture is usually several decades later, several exogenous factors such as diet and exercise may exert overriding influences on later bone health. Moreover, without contraception, the clinical outcome may be unwanted pregnancy and its potential impact on bone health.

SUMMARY

Recent findings suggest that depot medroxyprogesterone acetate and ultra-low dose oral contraceptives may interfere with achieving optimal peak bone mass in very young women; however, there may be substantial recovery after cessation of these methods and overriding long-term influences on bone health imposed by a myriad of lifestyle factors.

Longitudinal changes in bone density in relation to oral contraceptive use

The primary aim of this 36-month prospective cohort study was to evaluate the association between use of oral contraceptives (OCs) and bone mineral density in reproductive-age women. The 36-month bone density (g/cm2) at the spine, hip and whole body and percent change from baseline (measured at 6-month intervals) were evaluated among 245 women 18-39 years of age; 89 were using OCs (median duration: 3.7 years at study entry) and 156 were not using any hormonal contraception. Before and after adjustment for covariates (baseline bone density, age, race, ever pregnant, exercise, body mass and calcium intake), women using OCs did not differ significantly from comparison women in percent change in bone density over 36 months or in absolute bone density at 36 months. All p-values for between-group differences were >0.55. In conclusion, within the limitations of this study, OCs did not appear to impact bone density over time in this cohort of reproductive-age women.

Osteoporosis: prevention and treatment in anorexia nervosa

One of the most serious and potentially permanently disabling medical complications of anorexia nervosa is osteoporosis, which greatly increases the long-term risk of bone fractures. The decreased bone density in patients with anorexia nervosa (AN) is due to the many effects on bone metabolism of amenorrhea, reduced levels of insulin growth factor-1 (IGF-1), high cortisol levels and weight loss. Although estrogen replacement therapy is clearly efficacious in preventing postmenopausal osteoporosis, its efficacy in AN is uncertain. Clinicians caring for patients with AN need to be aware of this because, despite such therapy, there may be an inexorable decline in bone mineral density in what is a relatively young group of patients. AN frequently has its onset during adolescence, when peak bone mass is normally reached, and an anorectic episode in youth may permanently impair skeletal integrity and lead to debilitating fractures and pain. It is important to recognise this formidable risk, counsel AN patients about the longterm and possibly permanent sequelae of low body weight, use densitometry to screen for bone loss and treat it accordingly. The most effective treatment is still early weight restoration and the resumption of menses.

Four-year gain in bone mineral in girls with and without past forearm fractures: a DXA study. Dual energy X-ray absorptiometry

We have previously shown that girls with a recent distal forearm fracture have weaker skeletons than girls who have never fractured. This could be a transient or persistent phenomenon. The present study was undertaken to determine whether the bone mineral content (BMC) of girls with previous distal forearm fractures remains lower 4 years postfracture or if catch-up gain has occurred. We report baseline and follow-up dual energy X-ray absorptiometry (DXA) results for 163 girls: 81 girls from the original control group who remained free of fracture (group 1) and 82 girls from the original group with distal forearm fractures (group 2). In data adjusted for bone area, height, weight, and pubertal status, group 2 girls had 3.5-8.5% less BMC at the total body, lumbar spine, ultradistal radius, and hip trochanter than group 1 at baseline, and 2.4-5.7% less BMC at these sites at follow-up. Even girls from group 2 who did not experience another fracture after baseline (n = 58) did not display greater BMC at follow-up compared with baseline values at any site, indicating that the decreased BMC at the time of fracture had persisted. In group 2, the relative gain in BMC after adjusting for the initial BMC and current bone area, height, weight, and pubertal stage was less than or similar to, but not greater than that of group 1 (ratio [95% CI]: total body, 0.985 [0.972-0.998]; lumbar spine, 0.961 [0.935-0.987]; ultradistal radius, 0.968 [0.939-0.998]; hip trochanter, 0.955 [0.923-0.988]; femoral neck, 0.981 [0.956-1.007]; and 33% radius 0.999 [0.977-1.021]). These findings indicate that girls with distal forearm fractures do not improve their gain of BMC. We conclude that girls who have sustained a distal forearm fracture maintain their lower BMC at most sites for at least 4 years.