Forearm bone density in users of Depo-Provera as a contraceptive method

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 status after cessation of use of injectable progestin contraceptives

BACKGROUND

Women using injectable progestin contraceptives (IPCs) have lower bone mineral density than nonusers. We assessed whether bone loss is completely reversible after cessation of IPC use, whether different IPCs have different effects and whether effects vary by age at first use.

STUDY DESIGN

In a cross-sectional study in Cape Town, South Africa, 3487 premenopausal black and mixed race women aged 18-44 years were interviewed for information on contraceptive history and risk factors for decreased bone mineral density, and ultrasound measurements of the left calcaneus were taken. Adjusted means of the ultrasound measures for categories of IPC use were obtained using multivariable linear regression.

RESULTS

Current users of IPCs had the lowest ultrasound measures, while the measures of women who had ceased IPC use at least 2-3 years previously were similar to or greater than those of never users of IPCs. The effects of depot medroxyprogesterone acetate and norethisterone enanthate were similar. The calcaneus measures were unrelated to age at which use began after control for confounding factors.

CONCLUSION

The data suggest that bone loss during IPC use is reversible and that this loss of bone is completely recovered several years after cessation of use.

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.

Bone mineral density in users of two kinds of once-a-month combined injectable contraceptives

OBJECTIVE

The objective of this descriptive study was to compare bone mineral density (BMD) between users of two kinds of once-a-month combined injectable contraceptives (CICs) and control subjects.

SUBJECTS AND METHODS

This cross-sectional descriptive study included 97 women aged between 20 and 45 years using CICs containing either 25 mg of medroxyprogesterone acetate and 5 mg of estradiol cypionate for 12-82 months or 50 mg of norethindrone enanthate and 5 mg of estradiol valerate for 12-60 months, matched by age (+/-1 year) and body mass index (BMI; kg/m(2)) (+/-1) with users of the TCu 380A intrauterine device as control subjects. BMD was evaluated at the midshaft of the ulna and at the distal section of the radius of the nondominant forearm using double X-ray absorptiometry.

RESULTS

There was no difference in BMD between users of either CIC and nonusers at either section of the forearm studied. There was also no difference in BMD between users of the two CICs at either section of the forearm.

CONCLUSIONS

Women aged between 20 and 45 years, currently using one of these two kinds of CICs, presented BMDs similar to those of control subjects paired by age and BMI.

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.

A cross-sectional study of the forearm bone density of long-term users of levonorgestrel-releasing intrauterine system

BACKGROUND

There are concerns about the effect of hormonal contraceptives on bone mineral density (BMD), but there is currently no information available on the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) on BMD. The objective of this study was to compare the BMD of LNG-IUS users with that of controls using the TCu380A intrauterine device (IUD).

MATERIALS AND METHODS

A cross-sectional study paired 53 women, aged 25-51 years, who had been using the LNG-IUS for 7 years, with 53 IUD users, according to age (+/-1 year) and body mass index (BMI; kg/m2) (+/-1). BMD was evaluated at the midshaft of the ulna and the distal radius of the nondominant forearm using double X-ray absorptiometry.

RESULTS

Mean age of women was 34 years. BMI was slightly over 25 in both groups. Estradiol was normal. Mean BMD was 0.469 +/- 0.008 and 0.467 +/- 0.009 and 0.409 +/- 0.009 and 0.411 +/- 0.009 at the midshaft of the ulna and distal radius in LNG-IUS and IUD users, respectively, without significant differences.

CONCLUSIONS

Women aged 25-51 years, using the LNG-IUS for 7 years, had a mean BMD similar to that of the control group of TCu380A IUD users.

A prospective study of the forearm bone density of users of etonorgestrel- and levonorgestrel-releasing contraceptive implants

BACKGROUND

The aim of the study was to compare bone mineral density (BMD) before insertion and at 18 months of use of etonorgestrel- and levonorgestrel-releasing contraceptive implants.

METHODS

One hundred and eleven women, 19-43 years of age, were randomly allocated to two groups: 56 to etonorgestrel and 55 to levonorgestrel. BMD was evaluated at the midshaft of the ulna and at the distal radius of the non-dominant forearm using dual-energy X-ray absorptiometry before insertion and at 18 months of use.

RESULTS

There was no difference in baseline demographic or anthropometric characteristics, or in BMD of users of either model of implant. BMD was significantly lower at 18 months of use at the midshaft of the ulna in both groups of users. However, no difference was found at the distal radius. Multiple linear regression analysis showed that the variables associated with BMD at 18 months of use in both implant groups were baseline BMD, body mass index (BMI) and difference in BMI (0 versus 18 months of use).

CONCLUSIONS

Women of 19-43 years of age using either one of the implants showed lower BMD at 18 months of use at the midshaft of the ulna, however, without a difference at the distal radius.

Bone mineral density in women aged 40–49 years using depot-medroxyprogesterone acetate, norethisterone enanthate or combined oral contraceptives for contraception

Most studies show that depot-medroxyprogesterone acetate (DMPA) has a negative effect on bone mass. There are conflicting reports with respect to recovery of bone mass with long-term use of DMPA. No 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 older women (40-49 years) in relation to use of DMPA, NET-EN and COCs for at least 12 months preceding recruitment into the study. One-hundred twenty-seven users of DMPA, 102 NET-EN users and 106 COC users were compared to 161 nonuser controls. Bone mineral density was measured at the distal radius and midshaft of the ulna using dual X-ray absorptiometry. There was no significant difference in BMD between the four contraceptive user groups (p=.26) with and without adjustment for age. Although a small decrease in BMD was noted in the age range of 40-49 years, this was not statistically significant (p=.7). The BMD was found to be significantly associated with body mass index (BMI) (p<or=.0001) at both measurement sites, 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 >or=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). This study found no evidence that long-term use of DMPA, NET-EN and COCs affects BMD in this population.

The association between depot medroxyprogesterone acetate contraception and bone mineral density in adolescent women

Although adolescent women are actively acquiring bone, there has been little study of the possible effects of depot medroxyprogesterone acetate (DMPA) injectable contraception use on bone density in adolescents. We conducted a cross-sectional evaluation of the association between DMPA use and bone mineral density in adolescent women, ages 14-18 years. Of 174 study participants, 81 were DMPA users (range, 1-13 injections, median = 3) and 93 were not. Mean bone density at all anatomic sites (hip, spine and whole body) was lower for DMPA users than nonusers, but differences were not statistically significant (e.g., hip, 0.940 vs. 0.970 g/cm2, p = 0.10; spine, 0.970 vs. 0.992 g/cm2, p = 0.19). Duration of DMPA use showed a trend toward lower spine bone density (p-value for trend = 0.06). This study did not find a strong association between DMPA use and bone density. Further prospective evaluation of bone density changes with DMPA use and after DMPA discontinuation are needed in this age group.

Bone mineral density in adolescent females using depot medroxyprogesterone acetate

STUDY OBJECTIVE

To examine bone mineral density (BMD) on a semi-annual basis among control subjects and adolescent females receiving depot medroxyprogesterone acetate (DMPA) injection or oral contraceptives.

DESIGN

Non-randomized prospective study.

SETTING

Teenage pregnancy prevention intervention clinic.

PARTICIPANTS

Adolescent females who were new users of DMPA injection (N=58, age 12-21) or the oral contraceptive pill (N=71, age 11-19) and normal menstruating girls (N=19, age 15-18).

INTERVENTIONS

Baseline and 6-monthly measures of lumbar vertebral BMD using dual-energy X-ray absorptiometry over a 2-year period.

MAIN OUTCOME MEASURES

comparison of percent change on BMD over time between DMPA users, pill users, and normal menstruating girls.

RESULTS

There was no difference on group characteristics at baseline except for the ethnicity between the controls and the DMPA group. There was a statistically significant decrease in BMD between DMPA users and controls at 6 months (-3.02% change, P=0.014) 12 months (-3.38% change, P=0.001) 18 months (-4.81% change, P<0.001) and 24 months (-6.81% change, P=0.010). There was no statistical difference between pill users and controls.

CONCLUSION

There is a relationship between DMPA use and a decrease in BMD compared to normal menstruating controls that seems to persist up to 24 months.

Adolescent endometriosis

Endometriosis is a cause of chronic, pelvic pain in adolescents. Lack of response to NSAIDS and OCPs should prompt further investigation and subsequent treatment. The goal of therapy is to minimize pelvic pain and dysmenorrhea primarily through long-term, medical therapy. Surgical intervention is principally indicated to establish a diagnosis. The poor response to surgical therapy negates the need for repetitive or radical surgery. Much patience and care should be directed toward these patients to provide them with an understanding of their disease and to help enhance the quality of their life.

Controversies in adolescent hormonal contraception

Unintended pregnancy and abortion rates among US adolescents remain high although hormonal contraception is safe and effective in this population. Controversies affecting the provision of hormonal contraception for adolescents include the side effects of oral contraceptives, the possibility that progestin-only injectables lead to decreased bone health, and debate as to whether emergency contraception should be available to teens without a prescription. Each of these issues is addressed with a review of relevant literature.

A 2-year prospective study on the effects of depot medroxyprogesterone acetate on bone mass-response to estrogen and calcium therapy in individual users

The primary aim of this prospective 2-year follow-up study was to investigate the effect of depot medroxyprogesterone acetate (DMPA) on the maintenance of bone mass in women aged 30-45 years. The effects of estrogen or calcium substitution during the second year of follow-up was investigated in seven DMPA users with a high annual bone loss during the first year. The bone mass of 35 users of DMPA and 10 women without hormonal contraception was investigated using peripheral quantitative computed tomography. The baseline cortical and trabecular bone mass (TBM) and the annual change was not different in DMPA users and controls. Over 24 months we measured an increase in TBM of 0.6% and a decrease in cortical bone mass of 0.1% in exposed women. Some but not all of the DMPA users with a bone loss during the first year could be successfully treated with estradiol or calcium. In conclusion, we did not observe an accelerated bone loss in DMPA users aged 30-45 years.

Pharmacotherapeutics for osteoporosis prevention and treatment

Osteoporosis is a silent disease that affects 10 million Americans; 80% of those affected are women. Although the disease is more common in postmenopausal Caucasian women, all ages and races are at risk. Osteoporosis can be a debilitating disease that can cause pain, fractures, depression, and social withdrawal. Signs of osteoporosis include kyphosis, loss of height, and protrusion of the abdomen. Because symptoms generally do not occur until after the disease has progressed, clinicians should include osteoporosis screening and preventative education as part of the regular gynecologic care. Diagnosis is typically made by a dual energy x-ray absorptiometry (DEXA) scan. Treatment consists of dietary and lifestyle changes, along with pharmacologic intervention. Although hormone therapy has been shown to be effective in preventing osteoporosis, the risks of long-term treatment with HRT are discussed. The following effective treatment options for women who have been diagnosed with the disease are discussed: bisphosphonates, calcitonin, and selective estrogen receptor modulators (SERMs). Because midwives regularly care for women of all ages, they are ideal candidates to provide women with preventative education, screening, counseling, and treatment.

Injectable hormone contraception and bone density: results from a prospective study

BACKGROUND

Depot medroxyprogesterone acetate (DMPA) injectable contraception may decrease bone density and increase the risk for osteoporosis in later life. Prospective data are scarce, especially of the effects of DMPA discontinuation on bone.

METHODS

Between 1994 and 1999, we conducted a population-based prospective cohort study among women enrollees of a Washington State health maintenance organization. We enrolled 457 nonpregnant women, ages 18-39 years (183 DMPA users and 274 non-users). Bone density was measured by dual-energy x-ray absorptiometry every 6 months for 3 years.

RESULTS

Bone density decreased notably among DMPA-exposed women at the spine (adjusted mean bone density was -0.0053 gm/cm for DMPA users compared with +0.0023 gm/cm for non-users for each 6-month interval) and total hip (-0.0060 compared with -0.0002 gm/cm ). This represents an annualized mean rate of change at the spine of -0.87% compared with +0.40% and, at the hip, -1.12% compared with -0.05%. Discontinuers of this method (N = 110) showed sizable increases in bone density over comparison women (for each 6-month interval, adjusted mean spine bone density was +0.0067 gm/cm compared with +0.0023 gm/cm, respectively; adjusted mean hip bone density was +0.0035 compared with -0.0002 gm/cm ). Estimated annualized mean rates of change were +1.41% compared with +0.40% [corrected] at the spine and +1.03% [corrected] compared with -0.05% at the hip. After 30 months, mean bone density for discontinuers was similar to that of non-users.

CONCLUSIONS

In this study, DMPA use was strongly associated with bone density loss. Substantial postdiscontinuation recovery of bone provides evidence that the effects may be largely reversible.

Overview of the relationship between use of progestogen-only contraceptives and bone mineral density

OBJECTIVES

To summarise the available epidemiological evidence regarding the relationship between the use of progestogen-only contraceptives and bone mineral density.

DESIGN AND METHODS

Overview of the published epidemiological literature.

RESULTS

Overall, 17 studies of the use of progestogen-only contraceptives and bone mineral density were identified, involving 1529 women exposed to progestogen-only contraceptives and 2086 controls. Sixty-eight percent of the data relate to the effects of use of depot medroxyprogesterone acetate. Average bone mineral density was reduced in current users of depot medroxyprogesterone acetate compared with non-users, although density in users was within one standard deviation of the mean in non-users. There was significant heterogeneity between the results of different studies (P < 0.0001). The reduction in bone mineral density appeared to be greater at the lumbar spine, femoral neck and ultradistal forearm than at the midshaft of the ulna. Studies involving women with a longer average duration of use of depot medroxyprogesterone acetate displayed greater reductions in bone mineral density compared with studies of women with shorter durations of use. Based on limited data, no difference in bone mineral density was observed between former and never users of depot medroxyprogesterone acetate. Results regarding the effect of levonorgestrel implants were conflicting. Studies of progestogen-only oral contraceptives and the progesterone vaginal ring were small and restricted to lactating women.

CONCLUSIONS

Women currently using depot medroxyprogesterone acetate have a lower average bone mineral density than non-users. The magnitude of this effect is uncertain but appears to be greater with longer durations of use.

Forearm bone density in long-term users of oral combined contraceptives and depot medroxyprogesterone acetate

OBJECTIVE

To compare the bone mineral density of users of combined oral contraceptives (OC) or depot medroxyprogesterone acetate (depot-MPA) with women who have never used a hormonal contraceptive method.

DESIGN

Cross-sectional study.

SETTING

Academic tertiary-care hospital.

PATIENT(S)

A total of 189 women, aged 30 to 34 years old, were allocated to three groups: 63 who had used OC for at least 2 years; 63 who had used depot-MPA for at least 2 years; and 63 control women who had never used hormonal contraceptives.

INTERVENTION(S)

Each woman's bone mineral density (BMD) was evaluated at the distal and ultradistal section of the radius of the nondominant forearm by the use of single x-ray absorptiometry.

MAIN OUTCOME MEASURE(S)

We obtained BMD measurements for each participant.

RESULT(S)

Independent of the period of use and the section of the forearm studied, we found no difference in BMD for OC or depot-MPA users when compared to women who had never used hormonal contraceptive methods. In addition, BMD was similar between OC users and depot-MPA users. The multiple linear regression analysis showed that the variables associated with BMD were weight, number of pregnancies, and the woman's occupation.

CONCLUSION(S)

Women aged 30 to 34 years who have used OC or depot-MPA have similar BMD as control women. These findings suggest that the use of OC or depot-MPA does not affect the BMD of women in this age group.

Magnitude and variability of sequential estradiol and progesterone concentrations in women using depot medroxyprogesterone acetate for contraception

OBJECTIVE

To describe the magnitude and variability of sequential serum estradiol and progesterone concentrations throughout one depot medroxyprogesterone (DMPA) injection interval.

DESIGN

Prospective study.

SETTING

Family planning and women's health clinics.

PATIENT(S)

Thirty-one women, ages 19 to 46, using DMPA for contraception.

INTERVENTION(S)

Serum for estrogen and progesterone was collected weekly throughout one DMPA injection interval.

MAIN OUTCOME MEASURE(S)

Serum estradiol and progesterone concentrations; estradiol patterns produced from data plotted across the entire DMPA injection interval.

RESULT(S)

The average daily estradiol concentrations ranged from 7.9 to 69.1 pg/mL, with a mean of 18.9 +/- 12.9 and a median of 15.4 pg/mL. Average daily progesterone concentrations ranged from 0.14 to 1.1 ng/mL, with a mean of 0.40 +/- 0.19 ng/mL and a median of 0.36 ng/mL. Two general patterns of estradiol concentrations were identified. One pattern, observed in approximately one third of the participants, reflected estradiol concentrations that were extremely low (mean, 12.7 +/- 3.6 pg/mL; median, 13.4 pg/mL) and consistently flat across the DMPA injection interval. The second pattern, seen in the remaining participants, reflected estradiol concentrations that were higher (mean, 22.2 +/- 14.9 pg/mL; median, 17.3 pg/mL) and quite variable.

CONCLUSION(S)

This study demonstrated that estradiol concentrations were lower than the 40 to 50 pg/mL reported in most studies and, for the majority of women, varied substantially across the DMPA injection interval.

Medical and surgical therapies for pain associated with endometriosis

Endometriosis is a common condition for which a number of treatments have been proposed. Medical treatments are based on the hormonal responsiveness of endometriosis implants. These therapies include progestins (with or without estrogens), androgens, and gonadotropin-releasing hormone (GnRH) analogs. Surgical treatments may include hysterectomy with oophorectomy or organ-sparing surgery involving ablation or resection of visible lesions of endometriosis and restoration of pelvic anatomy. There are no studies that directly compare the effectiveness or adverse effects of medical therapy and surgical therapy. Studies on medical therapy compare different treatments with placebo or with other active treatments. Hormone-based therapies for endometriosis show 80%-100% effectiveness in relief of pelvic pain over a 6-month course of therapy. Serious adverse outcomes after medical therapy are unusual. Studies on surgical therapy are largely anecdotal, with noncomparative reports on a variety of surgical methods. A few comparative surgical studies have been reported. Because of the noncomparative nature of many of the surgical studies, the use of combinations of surgical procedures and techniques in the reported studies, and the reporting of results from surgeons with an unusually high level of technical skill, the gynecological practitioner has little basis in the literature for assessing the optimum surgical approach. Surgical complications are believed to be underreported and may be related to how aggressive a surgical procedure is undertaken.

Injectable contraception. New and existing options

DMPA and MPA/E2C contraception offer women safe, effective, convenient, and reversible birth control choices. The use of DMPA, a 3-month injectable, is characteristically associated with amenorrhea. Lactating women and women in whom contraceptive doses of estrogen are contraindicated can use this progestin-only birth control method. Return of fertility can be delayed in women discontinuing DMPA to become pregnant. In some cases, the use of DMPA also confers important noncontraceptive and therapeutic benefits. A monthly estrogen/progestin injectable contraceptive, MPA/E2C should appeal to women who are concerned about daily pill taking, who prefer regular cycles to amenorrhea, and who find monthly injections acceptable and accessible. As is true for oral contraceptives, MPA/E2C represents an appropriate choice for women who prefer a rapidly reversible contraceptive. Currently, the proposed contraindications for MPA/E2C parallel those for combined oral contraceptives. As MPA/E2C contraception becomes available for American women, clinicians will learn how to best include this new method among the array of contraceptive choices. By individualizing contraceptive selection, counseling, and management approaches based on the relevant behavioral and medical considerations reviewed herein, clinicians can maximize their patients' success with injectable contraceptives. The more innovative that clinicians, family planning agencies, and insurers are in facilitating access to care (including reinjections), the more women will be able to avail themselves of safe, effective, and reversible methods of contraception. In addition to the physician's office or health clinic, other sites at which women might receive contraceptive injections include employee health clinics, college health clinics, or perhaps the pharmacy where the prescription is filled. Self-administration may become an appropriate option for some users of injectable contraception.

Further evaluation on long-term depot-medroxyprogesterone acetate use and bone mineral density: a longitudinal cohort study

Cross-sectional studies on the effects of depot-medroxyprogesterone acetate (DMPA) on bone mineral density (BMD) have been controversial. The present longitudinal cohort study on 59 Chinese women over a period of 3 years has shown that their annual rate of bone loss at 3 sites (0.44% in lumbar spine, 0.40% in neck of femur, 1.05% in Ward's triangle) was substantially less than the projected values (1.1% in lumbar spine, 2.3% in neck of femur, 3.5% in Ward's triangle) in a cross-sectional study that had demonstrated a significant reduction in BMD in DMPA users than the non-user population. The trochanter BMD measurement did not show the projected annual bone loss of 2.4%. The rate of bone loss is probably non-linear, with a rapid loss in the first 5 years and a leveling off afterwards. The duration of DMPA use was not significantly correlated with the rate of bone loss. Multiple linear regression analysis demonstrated that age and body mass index were significant variables in modeling the rate of bone loss in the lumbar spine and neck of femur, but not in the trochanter and Ward's triangle areas. The Z scores also suggested a retardation in bone loss with time and potentially due to the effect of progesterone in decreasing bone turnover that is similar to the situation in postmenopausal women. The present data provide another aspect of reassurance to the long-term use of DMPA.

A prospective study on the effects of depot medroxyprogesterone acetate on trabecular and cortical bone after attainment of peak bone mass

OBJECTIVE

To study the annual change of bone mass in women aged 30-45 years being treated with depot medroxyprogesterone acetate (DMPA) in order to evaluate whether the bone mass depends on the duration of DMPA use or the oestradiol level.

DESIGN

Prospective longitudinal study over an interval of 12 months.

SETTING

A family planning centre of a university hospital.

PATIENTS

Thirty-six current users of DMPA.

INTERVENTIONS

Injection of 150 mg DMPA every 12 weeks.

MEASUREMENTS

Bone mass was measured at the distal radius by peripheral quantitative computed tomography (reproducibility 0.3%).

RESULTS

Mean annual changes (SD) in trabecular and cortical bone mass were 0.06 (1.6%) [P = 0.8] and -0.26% (0.6) [P < 0.04]. The decrease in cortical bone mass was not significant because the changes were within the precision error of the method used for the measurements. Duration of DMPA use and oestradiol levels were not associated to the bone parameters.

CONCLUSION

We did not find a negative impact of DMPA on the bone mass of premenopausal women aged 30-45 years.