Bone mineral density in adolescent and young Thai girls receiving oral contraceptives compared with depot medroxyprogesterone acetate: a cross-sectional study in young Thai women

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.

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.

Relationship between weight and bone mineral density in adolescents on hormonal contraception

STUDY OBJECTIVE

Since bone loss has been observed among adolescents on depot medroxyprogesterone acetate (DMPA), a clinical population that commonly experiences weight gain, we were interested in examining the direct relationship between body weight and bone mineral density (BMD) in adolescents on DMPA as compared to those on oral contraceptive pills (OC) or on no hormonal contraception (control).

DESIGN

Prospective, Longitudinal study.

SETTING

Four urban adolescent health clinics in a large metropolitan area.

PARTICIPANTS

Postmenarcheal girls, age 12-18 years, selecting DMPA, OC or no hormonal contraception.

INTERVENTIONS

At baseline, 6, 12, 18, and 24 months, all study participants underwent measurement of weight and BMD of the hip and spine.

MAIN OUTCOME MEASURES

The correlation between weight and BMD, and the correlation between change in weight and change in BMD were assessed at each time point.

RESULTS

Body weight was significantly (P < 0.05) positively correlated with femoral neck BMD and spine BMD at each time point regardless of contraceptive method. Change in body weight at 12 and 24 months was highly correlated with change in femoral neck BMD (P < 0.0001) for all treatment groups. No statistically significant correlation between change in weight and change in spine BMD was seen in the DMPA, OC, or control subjects at 12 or 24 months.

CONCLUSION

Weight gain on DMPA may mitigate loss of BMD among adolescent users.

Bone mineral density in a cohort of adolescents during use of norethisterone enanthate, depot-medroxyprogesterone acetate or combined oral contraceptives and after discontinuation of norethisterone enanthate

BACKGROUND

Depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN) and combined oral contraceptives (COCs) have been shown to have a negative effect on bone mineral density (BMD) in adolescents. The aim of this study was to investigate BMD in 15- to 19-year-old new users of DMPA, NET-EN and COCs.

STUDY DESIGN

This 5-year longitudinal study followed up new users of DMPA (n=115), NET-EN (n=115) and COCs (n=116) and 144 nonuser controls. BMD was measured at the distal radius using dual-energy X-ray absorptiometry.

RESULTS

BMD increased in all groups (annual percent increase: nonusers, 1.49%; DMPA, 1.39%; NET-EN, 1.03%; COCs, 0.84%) during follow-up (p<.001). There was evidence for lower BMD increases per annum in NET-EN (p=.050) and COC (p=.010) users compared to nonusers but no difference between DMPA and nonusers (p=.76). In 14 NET-EN discontinuers, an overall reduction of 0.61% per year BMD was followed upon cessation by an increase of 0.69% per year (p=.066).

CONCLUSION

This study suggests that BMD increases in adolescents may be less in NET-EN and COC users; however, recovery of BMD in NET-EN users was found in the small sample of adolescents followed post-discontinuation.

Bone density recovery after depot medroxyprogesterone acetate injectable contraception use

BACKGROUND

While depot medroxyprogesterone acetate (DMPA) is a highly effective contraceptive used by millions of women, its use is associated with bone mineral density (BMD) loss, raising concerns about long-term risk of osteoporosis and/or fractures.

STUDY DESIGN

We conducted a systematic review of studies published in PubMed from 1996 to 2006, evaluating changes in BMD after discontinuation of DMPA. Ten primary clinical or observational studies were identified addressing this issue.

RESULTS

BMD consistently returned toward or to baseline values following DMPA discontinuation in women of all ages. This recovery in BMD was seen as early as 24 weeks after stopping therapy and persisted for as long as women were followed up; BMD in past DMPA users was similar to that in nonusers.

CONCLUSIONS

Bone loss occurring with DMPA use is reversible and is not likely to be an important risk factor for low bone density and fractures in older women, although data on fracture risk in DMPA users are lacking.

Bone mineral density in adolescents using norethisterone enanthate, depot-medroxyprogesterone acetate or combined oral contraceptives for contraception

PURPOSE

Most studies have shown a negative effect of depot-medroxyprogesterone acetate (DMPA) on the bone mineral density (BMD) of adolescents. There is no information available on the effect of norethisterone enanthate (NET-EN) on BMD in adolescents and the effect of combined oral contraceptives (COCs) on adolescent BMD is inconclusive. The aim of this longitudinal study was to investigate BMD in adolescent (aged 15-19 years) new users of hormonal contraception (DMPA, NET-EN and COCs).

METHOD

New users of DMPA (n=115), NET-EN (n=115), COCs (n=116) and 144 nonuser controls were recruited. BMD was measured at the distal radius and midshaft of the ulna using dual X-ray absorptiometry.

RESULTS

In total, 275 women were included in this interim analysis and total follow-up time was 553 person-years. There was no significant difference in radius BMD between users of different contraceptive methods at baseline (p=.40). Overall, an increase in radius BMD of 0.00522 per person-year was observed. This result was similar when adjusting for BMI in the random effects regression model (p=.88). The regression model showed that BMI was significantly associated with radius BMD, with each unit increase in BMI corresponding to an increase of 0.0029 g/cm2 in BMD (95% CI 0.0023 to 0.0036, p<.001). Interaction between contraceptive method and follow-up time adjusted for BMI was not significant (p=.07). The increase in BMD for NET-EN users of 0.0013 g/cm2 per person-year (95% CI -0.0017 to 0.0043) was significantly lower than that of nonusers (p=.017). For DMPA and COC users, the increase in BMD was not significantly different compared to the nonusers. This study suggests that NET-EN users had lower increase in BMD over time compared to the other user groups.

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.

Effects of the long-term use of depot medroxyprogesterone acetate as hormonal contraceptive on bone mineral density and biochemical markers of bone remodeling

PURPOSE AND METHOD

Our objective is to evaluate the effects of the long-term use of depot medroxyprogesterone acetate (DMPA) as a method of contraception on bone mineral density (BMD) and bone remodeling. Forty women (21-44 years old) who used DMPA for contraception for <1, 1-2 and >5 years, in addition to 20 age-matched healthy women (nonusers), participated in this study. Lumbar spine BMD (LS-BMD) was measured by dual-energy X-ray absorptionmetry. Serum osteocalcin (OC), a bone formation marker, was measured by enzyme amplification sorbent immunoassay. Urinary deoxypyridinoline (DPD), a bone resorption marker, was determined by enzyme immunoassay.

RESULTS

Serum OC and urinary DPD levels in women who used DMPA for <1, 1-2 and >5 years were significantly increased compared to the corresponding levels in nonusers. The increase of both biomarkers was more pronounced with longer duration of use. LS-BMD was significantly decreased in women on long-term DMPA use compared to LS-BMD in nonusers. The mean percentage decrease of LS-BMD in women who used DMPA for 1-2 and >5 years was 9% and 11.8%, respectively. LS-BMD was negatively correlated with serum OC and urinary DPD in women who used DMPA. On the other hand, LS-BMD and bone turnover were not significantly different between women who used DMPA for <1 year and nonusers.

CONCLUSION

Long-term use of DMPA (>2 years) had a significant adverse effect on BMD and induced increased bone turnover, as evidenced by a significant increase in biochemical indices of bone formation and resorption. The measurement of LS-BMD and of biomarkers of bone turnover may be recommended in women aged above 40 years and who used DMPA for a long duration (2-5 years).

Progestogen-only contraception and bone mineral density: a systematic review

Questions have been raised about the effects of progestogen-only contraceptive use on bone health, particularly among young women who have not yet reached peak bone mass and perimenopausal women who may be starting to lose bone mass. We conducted a systematic review that evaluated the association between progestogen-only contraceptive use and fracture risk or bone mineral density (BMD). We identified 39 articles from MEDLINE and EMBASE, published through July 2005. One study reported that depot medroxyprogesterone acetate (DMPA) users were more likely to experience stress fractures than nonusers; this association was not statistically significant after controlling for baseline bone density. In cross-sectional studies, the mean BMD in DMPA users was usually below that of nonusers, but within 1 SD. In longitudinal studies, BMD generally decreased more over time among DMPA users than among nonusers, but women gained BMD upon discontinuation of DMPA. Limited evidence suggested that use of progestogen-only contraceptives other than DMPA did not affect BMD.

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 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.

Overview on the effects of progestins on bone

In view of the fact that fractures are the clinically relevant events, risk factors for fractures are discussed first. Bone mineral density (BMD) appears to be a much less important risk factor for the most severe hip fractures than the risk of falling. No results of experimental studies on hormones and fractures at advanced age are available. An overview of the effects of progestins on bone is given. Effects of progestins on bone have been studied by in vitro experiments using cell lines and by more relevant clinical observations. Prospective studies have been conducted following the use of progestins contained in oral contraceptives, alone or in combination with oestrogens; long-term contraception by injection of depot preparations; so-called "add-back" hormonal therapy attempting to reverse the adverse effects of gonadotropin releasing hormone agonists on bone and after different regimens of hormone replacement therapy (HRT) in postmenopausal women. From the data there are no indications that the various progestins, used in clinical practice, have either a bone-protective or an oestrogen antagonistic activity. Progestins do not add or subtract much of the protective action of oestrogens on the bones.

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.

Depot-medroxyprogesterone acetate injection (Depo-Provera): a highly effective contraceptive option with proven long-term safety

Depot-medroxyprogesterone acetate (Depo-Provera(R)) is a highly effective, nondaily hormonal contraceptive option that has been available in the United States for a decade, and worldwide for 40 years. Benefits and risks of hormonal therapy are often under scrutiny; however, long-term clinical experience has established the safety of this long-acting contraceptive. This article reviews the contraceptive efficacy, potential noncontraceptive health benefits and long-term safety of with regard to risk of cardiovascular events, breast and gynecologic malignancy and osteopenia. Comparisons with other hormonal contraceptives are made as clinically appropriate. Common patient management issues, including effects on menstrual cycle, body weight and mood, are also addressed. Finally, this review provides recommendations for appropriate patient selection.