Short-term variations in bone remodeling markers of an oral contraception formulation containing 3 mg of drospirenone plus 30 μg of ethinyl estradiol: Observational study in young postadolescent women

U.S. Medical Eligibility Criteria for Contraceptive Use, 2024

The 2024 U.S. Medical Eligibility Criteria for Contraceptive Use (U.S. MEC) comprises recommendations for the use of specific contraceptive methods by persons who have certain characteristics or medical conditions. These recommendations for health care providers were updated by CDC after review of the scientific evidence and a meeting with national experts in Atlanta, Georgia, during January 25-27, 2023. The information in this report replaces the 2016 U.S. MEC (CDC. U.S. Medical Eligibility Criteria for Contraceptive Use, 2016. MMWR 2016:65[No. RR-3]:1-103). Notable updates include 1) the addition of recommendations for persons with chronic kidney disease; 2) revisions to the recommendations for persons with certain characteristics or medical conditions (i.e., breastfeeding, postpartum, postabortion, obesity, surgery, deep venous thrombosis or pulmonary embolism with or without anticoagulant therapy, thrombophilia, superficial venous thrombosis, valvular heart disease, peripartum cardiomyopathy, systemic lupus erythematosus, high risk for HIV infection, cirrhosis, liver tumor, sickle cell disease, solid organ transplantation, and drug interactions with antiretrovirals used for prevention or treatment of HIV infection); and 3) inclusion of new contraceptive methods, including new doses or formulations of combined oral contraceptives, contraceptive patches, vaginal rings, progestin-only pills, levonorgestrel intrauterine devices, and vaginal pH modulator. The recommendations in this report are intended to serve as a source of evidence-based clinical practice guidance for health care providers. The goals of these recommendations are to remove unnecessary medical barriers to accessing and using contraception and to support the provision of person-centered contraceptive counseling and services in a noncoercive manner. Health care providers should always consider the individual clinical circumstances of each person seeking contraceptive services. This report is not intended to be a substitute for professional medical advice for individual patients; when needed, patients should seek advice from their health care providers about contraceptive use.

Bone Turnover Markers: Basic Biology to Clinical Applications

Bone turnover markers (BTMs) are used widely, in both research and clinical practice. In the last 20 years, much experience has been gained in measurement and interpretation of these markers, which include commonly used bone formation markers bone alkaline phosphatase, osteocalcin, and procollagen I N-propeptide; and commonly used resorption markers serum C-telopeptides of type I collagen, urinary N-telopeptides of type I collagen and tartrate resistant acid phosphatase type 5b. BTMs are usually measured by enzyme-linked immunosorbent assay or automated immunoassay. Sources contributing to BTM variability include uncontrollable components (e.g., age, gender, ethnicity) and controllable components, particularly relating to collection conditions (e.g., fasting/feeding state, and timing relative to circadian rhythms, menstrual cycling, and exercise). Pregnancy, season, drugs, and recent fracture(s) can also affect BTMs. BTMs correlate with other methods of assessing bone turnover, such as bone biopsies and radiotracer kinetics; and can usefully contribute to diagnosis and management of several diseases such as osteoporosis, osteomalacia, Paget's disease, fibrous dysplasia, hypophosphatasia, primary hyperparathyroidism, and chronic kidney disease-mineral bone disorder.

Bone metabolic marker concentrations across the menstrual cycle and phases of combined oral contraceptive use

There is a need to further understand the impact of the menstrual cycle and phase of combined oral contraceptive (COC) use on the pre-analytical variability of markers of bone metabolism in order to improve standardisation procedures for clinical practice and research. The aim of this study was to assess bone metabolism marker concentrations across the menstrual cycle and phases of COC use. Carboxy-terminal cross-linking telopeptide of type I collagen (β-CTX), procollagen type 1 N propeptide (P1NP) and Bone alkaline phosphatase (Bone ALP) concentrations were assessed in eumenorrheic women (n = 14) during the early follicular, ovulatory and mid-luteal phases of the menstrual cycle and in COC (Microgynon®) (n = 14) users on day 2-3 of pill consumption (PC1), day 15-16 pill consumption (PC2) and day 3-4 of the pill free interval (PFI). β-CTX was significantly (-16%) lower at PC2 compared to PC1 (P = 0.015) in COC users and was not affected by menstrual cycle phase (P > 0.05). P1NP and Bone ALP were not significantly different across either menstrual cycle phase or phase of COC use (all P > 0.05). There was no difference in pooled bone marker concentrations between eumenorrheic women and COC users (P > 0.05). In contrast to some previous studies, this study showed that bone marker concentrations do not significantly fluctuate across the menstrual cycle. Furthermore, bone resorption markers are significantly affected by phase of COC use, although bone formation markers do not significantly vary by COC phase. Therefore, the phase of COC use should be considered in clinical practice and research when assessing markers of bone metabolism as this can impact circulating concentrations of bone metabolic markers yet is not currently considered in existing guidelines for best practice.

One-year adolescent bone mineral density and bone formation marker changes through the use or lack of use of combined hormonal contraceptives

OBJECTIVE

The objective of this study was to evaluate the effects of two low-dose combined oral contraceptives on bone metabolism in adolescents for one year.

METHODS

This was a quasi-experimental study. The adolescents were divided into three groups: oral contraceptives 1 (n=42) (20μg EE/150μg desogestrel), oral contraceptives 2 (n=66) (30μg EE/3mg drospirenone), and a control group (n=70). Adolescents underwent anthropometric assessment and densitometry (dual-energy X-ray). Bone age and bone formation markers (osteocalcin and bone alkaline phosphatase) were evaluated. The oral contraceptives users were evaluated again after 12 months. Linear regression analysis was used to indirectly study the effect of each additional year of chronological age on anthropometric and densitometric variables as well as on bone markers in the control group.

RESULTS

At study entry, no significant differences were observed between the oral contraceptives 1, oral contraceptives 2, and controls in the analyzed variables. Linear regression analysis showed an increase in bone mineral density and bone mineral content for each additional year. There was a significant reduction in bone alkaline phosphatase levels; no significant difference was observed for osteocalcin in control individuals. Comparison of dual-energy X-ray variables at baseline and after one year showed no significant differences in the oral contraceptives 1 or oral contraceptives 2 groups. A significant reduction in bone alkaline phosphatase and osteocalcin levels was observed in both the oral contraceptives 1 and oral contraceptives 2 groups.

CONCLUSION

Adolescent women gain peak bone mass during this phase of life. Two low-dose combined oral hormonal contraceptives were associated with lower bone gain and lower bone formation markers than in untreated controls.

Emotional Memory in Oral Contraceptive Users: Negative Stimuli Are More Forgettable

Recent research suggests oral contraceptive use is associated with altered memory for emotional story information, blunted stress hormone responses to emotional stimuli, and altered structure or function of the amygdala and hippocampus. This study examined the extent to which oral contraceptives influence relative recall of (a) the spatial location of emotional versus neutral stimuli and (b) positive versus negative emotional stimuli. Participants (58 oral contraceptive users, 40 nonusers, and 37 men) completed an Emotional Spatial Memory test and were evaluated on short-term recall and long-term (one week) recall. There was no evidence for group differences in recall of the locations of emotional versus neutral stimuli. However, oral contraceptive users remembered relatively more positive than negative items compared with nonusers and men on the spatial memory test. This effect was driven by oral contraceptive users recalling fewer negative items than free cyclers. The results indicate that hormonal contraceptives may decrease immediate recall of negative emotional stimuli.

Consensus Statement on the Use of Oral Contraceptive Pills in Polycystic Ovarian Syndrome Women in India

OBJECTIVE

To provide consensus recommendations for health-care providers on the use of oral contraceptive pills (OCPs) in polycystic ovarian syndrome (PCOS) women in India.

PARTICIPANTS

Extensive deliberations, discussions, and brainstorming were done with different fraternities (specialists) being involved. These included endocrinologists, gynecologists, reproductive endocrinologists, dermatologists, public health experts, researchers, and a project manager with a team to develop the guideline.

EVIDENCE

Published literature was retrieved through searches of Medline and The Cochrane Database from January 2003 to December 2017 using appropriate-controlled vocabulary (e.g., oral contraceptive pills, polycystic ovarian syndrome, long term outcomes, infertility). Clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies' publications and data were also reviewed to suggest the recommendations.

PROCESS

The working group for guideline committee included members from the PCOS Society (India), Indian Society for Assisted Reproduction, The Mumbai Obstetric and Gynecological Society, The Endocrine Society of India, Indian Association of Dermatologists, Venereologists and Leprologists, Cosmetic Dermatology Society (India), Academicians from Medical Colleges, National Institute for Research in Reproductive Health, and a Research Associate. The core team included five reproductive endocrinologists, five gynecologists, five dermatologists, three endocrinologists, two public health experts and one research associate.

CONCLUSIONS

This consensus statement provides the guidance/recommendations for Indian practitioners regarding the use of OCP in women with PCOS. PCOS is one of the common endocrinopathies encountered in gynecological/endocrine practice. The spectrum of this disorder may range from prepubertal girls with premature pubarche, young girls with hirsutism, acne and anovulatory cycles, married women with infertility, and elderly women. Although obesity is a common feature for most PCOS patients, 'lean PCOS' also exists. For several years, OCPs have played an important role in the symptom management of PCOS women. This is due to the fact that OCPs decrease the luteinizing hormone, reduce androgen production, and increase sex hormone-binding globulin, which binds androgens. Several new formulations of OCPs have been developed to decrease the side effects. This includes use of less androgenic progestins and lower doses of ethinyl estradiol. These consensus recommendations help the health provider to choose the right type of OCPs, which will alleviate the symptoms with least side effects. It also gives insight into the indications, contraindications, and concerns regarding its short, intermediate and long-term use.

A summary of the influence of exogenous estrogen administration across the lifespan on the GH/IGF-1 axis and implications for bone health

Bone growth, development, and remodeling are modulated by numerous circulating hormones. Throughout the lifespan, the extent to which each of the hormones impacts bone differs. Understanding the independent and combined impact of these hormones on controlling bone remodeling allows for the development of more informed decision making regarding pharmacology, specifically the use of hormonal medication, at all ages. Endocrine control of bone health in women is largely dictated by the growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis and the hypothalamic-pituitary-ovarian (HPO) axis. Growth hormone, secreted from the pituitary gland, stimulates cells in almost every tissue to secrete IGF-1, although the majority of circulating IGF-1 is produced hepatically. Indeed, systemic IGF-1 concentrations have been found to be correlated with bone mineral density (BMD) in both pre- and post-menopausal women and is often used as a marker of bone formation. Sex steroids produced by the ovaries, namely estradiol, mediate bone resorption through binding to estrogen receptors on osteoclasts and osteoblasts. Specifically, by increasing osteoclast apoptosis and decreasing osteoblast apoptosis, adequate estrogen levels prevent excessive bone resorption, which helps to explain the rapid decline in bone mass that occurs with the menopausal decrease in estrogen production. Though there are documented correlations between endogenous estrogen concentrations and GH/IGF-1 dynamics, this relationship changes across the lifespan as sex-steroid dynamics fluctuate and, possibly, as tissue responsiveness to GH stimulation decreases. Aside from the known role of endogenous sex steroids on bone health, the impact of exogenous estrogen administration is of interest, as exogenous formulations further modulate GH and IGF-1 production. However, the effect and extent of GH and IGF-1 modulation seems to be largely dependent on age at administration and route of administration. Specifically, premenopausal women using combined oral contraceptive therapy (COC), post-menopausal women taking oral hormone therapy (HT), and both pre- and post-menopausal women using a transdermal form of estrogen therapy (COC or HT) demonstrate disparate GH/IGF-1 responses to exogenous estrogen. This review serves to summarize what is currently known regarding the influence of exogenous estrogen administration across the lifespan on the GH/IGF-1 axis and implications for bone health.

Unique effects on hepatic function, lipid metabolism, bone and growth endocrine parameters of estetrol in combined oral contraceptives

OBJECTIVES

Estetrol (E4) is a natural estrogen produced by the human fetal liver. In combination with drospirenone (DRSP) or levonorgestrel (LNG), E4 blocks ovulation and has less effect on haemostatic biomarkers in comparison with ethinylestradiol (EE) combined with DRSP. This study evaluates the impact of several doses of E4/DRSP and E4/LNG on safety parameters such as liver function, lipid metabolism, bone markers and growth endocrine parameters.

METHODS

This was a dose-finding, single-centre, controlled study performed in healthy women aged 18 to 35 years with a documented pretreatment ovulatory cycle. Participants received 5 mg or 10 mg E4/3 mg DRSP; 5 mg, 10 mg or 20 mg E4/150 μg LNG; or 20 μg EE/3 mg DRSP as a comparator for three consecutive cycles in a 24/4-day regimen. Changes from baseline to end of treatment in liver parameters, lipid metabolism, bone markers and growth endocrinology were evaluated.

RESULTS

A total of 109 women were included in the study. Carrier proteins were minimally affected in the E4/DRSP and E4/LNG groups, in comparison with the EE/DRSP group, where a significant increase in sex hormone-binding globulin was observed. Similarly, minor effects on lipoproteins were observed in the E4 groups, and the effects on triglycerides elicited by the E4 groups were significantly lower than those in the EE/DRSP group. No imbalances in bone markers were observed in any groups. No alterations in insulin-like growth factor were observed in the E4 groups.

CONCLUSIONS

E4-containing combinations have a limited effect on liver function, lipid metabolism, and bone and growth endocrine parameters.

Steroidal contraceptives: effect on bone fractures in women

BACKGROUND

Steroidal contraceptive use has been associated with changes in bone mineral density in women. Whether such changes increase the risk of fractures later in life is not clear. Osteoporosis is a major public health concern. Age-related decline in bone mass increases the risk of fracture, especially of the spine, hip, and wrist. Concern about bone health influences the recommendation and use of these effective contraceptives globally.

OBJECTIVES

To evaluate the effect of using hormonal contraceptives before menopause on the risk of fracture in women

SEARCH STRATEGY

We searched for studies of fracture or bone health and hormonal contraceptives in MEDLINE, POPLINE, CENTRAL, EMBASE, and LILACS, as well as ClinicalTrials.gov and ICTRP. We wrote to investigators to find additional trials.

SELECTION CRITERIA

Randomized controlled trials (RCTs) were considered if they examined fractures, bone mineral density (BMD), or bone turnover in women with hormonal contraceptive use prior to menopause. Interventions could include comparing a hormonal contraceptive with a placebo or another hormonal contraceptive or could compare providing a supplement versus a placebo.

DATA COLLECTION AND ANALYSIS

We assessed all titles and abstracts identified through the literature searches. Mean differences were computed using the inverse variance approach. For dichotomous outcomes, the Mantel-Haenszel odds ratio (OR) was calculated. Both included the 95% confidence interval (CI) and used a fixed-effect model. Due to different interventions, no trials could be combined for meta-analysis.

MAIN RESULTS

Of the 16 RCTs we found, 2 used a placebo and 1 used a non-hormonal method as the comparison, while 13 compared two hormonal contraceptives. No trial had fracture as an outcome. Most measured BMD and several assessed bone turnover. Depot medroxyprogesterone acetate (DMPA) was associated with decreased bone mineral density. The placebo-controlled trials showed BMD increases for DMPA plus estrogen supplement and decreases for DMPA plus placebo. Combination contraceptives did not appear to negatively affect bone health, but none were placebo-controlled. For implants, the single-rod etonogestrel group showed a greater BMD decrease versus the two-rod levonorgestrel group. However, results were not consistent across all implant comparisons.

AUTHORS' CONCLUSIONS

Whether steroidal contraceptives influence fracture risk cannot be determined from existing information. Many trials had small numbers of participants and some had large losses to follow up. Health care providers and women should consider the costs and benefits of these effective contraceptives. For example, injectable contraceptives and implants provide effective, long-term birth control yet do not involve a daily regimen. Progestin-only contraceptives are considered appropriate for women who should avoid estrogen due to medical conditions.

Update on hormonal contraception and bone density

Combination hormonal contraception and progestin-only contraception (including depot medroxyprogesterone acetate [DMPA]) are effective and convenient forms of reversible contraception that millions of women use worldwide. In recent years, observations of reduced bone mineral density in current users of these methods have led to concerns that this hormone-induced bone loss might translate into long-term increased fracture risk. Special focus has been placed on adolescent users who have not yet attained their peak bone mass as well as perimenopausal users. In 2004, the FDA added a black box warning to DMPA package labeling warning of the risk of significant bone loss and cautioning against long-term use (> 2 years). This article reviews evidence on the use of hormonal contraception and its effect on bone density in adolescent, premenopausal, and perimenopausal populations. Recommendations from reproductive healthcare organizations are reviewed and clinical recommendations are provided.

Low-dose oral contraceptives in adolescents: how low can you go?

CONTEXT

The use of combined oral contraception (COC) before the accrual of peak bone mass in adolescents is common. Despite the tendency to prescribe lower ethinyl estradiol concentrations so as to reduce thromboembolic complications, concerns have developed as to whether low-dose COC provides sufficient estrogen supplementation for adequate adolescent bone development.

OBJECTIVE

This paper reviews the available literature on bone mineral density (BMD) and low-dose COC in adolescents in an effort to determine whether adult-oriented recommendations for the lowest tolerated estrogen dose should apply to adolescent populations.

DESIGN

A MEDLINE search of all English-language literature (1966 to January 2008) was performed using the terms "adolescent," "oral contraception," and "BMD." Bibliographies were reviewed to extract additional relevant sources. Articles were selected based on pertinence to BMD changes in association with low-dose (20 microg ethinyl estradiol) hormonal contraception with emphasis on adolescent study groups.

RESULTS

A limited number of studies examining 20-microg preparations in adolescents have demonstrated a significantly smaller mean percentage BMD acquisition in COC groups vs untreated controls. Bone mineral density decreases appeared to positively correlate with early gynecological age of first COC use and treatment duration.

CONCLUSIONS

Loss of bone mass as a result of hormonal contraceptive use may have serious long-term implications in the adolescent population, who have yet to achieve peak bone density. Both age at first COC use and cumulative estrogen dose appear to be important factors in determining skeletal development in adolescents. Further studies are warranted to inform specific prescribing practices for this population.

The effects of hormonal contraceptives on bone turnover markers and bone health

Sex hormones are important regulators of bone metabolism. As hormonal contraceptives contain either oestrogens or progestins, or a combination thereof, it is conceivable that these widely used agents have an effect on bone metabolism and bone health. The main users of hormonal contraceptives, adolescent girls and young women, are still building bone and accruing bone mass and may therefore be particularly susceptible to the effects of hormonal contraceptives on bone. Despite these concerns, the effects of hormonal contraceptives on bone health are still poorly understood. As biochemical markers of bone turnover have been proven useful tools in the assessment and monitoring of bone metabolism, we reviewed the effects of combined and gestagen-only hormonal contraceptives on bone turnover markers and related effects on bone mineral density and fracture risk in premenopausal women, as documented in the literature until January 2009.

Steroidal contraceptives: effect on bone fractures in women

BACKGROUND

Steroidal contraceptive use has been associated with changes in bone mineral density in women. Whether such changes increase the risk of fractures later in life is not clear. However, osteoporosis is a major public health concern. Age-related decline in bone mass increases the risk of fracture, especially of the spine, hip, and wrist. Concern about bone health influences the recommendation and use of these effective contraceptives globally.

OBJECTIVES

To evaluate the effect of using hormonal contraceptives before menopause on the risk of fracture in women

SEARCH STRATEGY

We searched for studies of fracture or bone health and hormonal contraceptives in MEDLINE, POPLINE, CENTRAL, EMBASE, and LILACS, as well as in clinical trials databases (ClinicalTrials.gov and ICTRP). We wrote to investigators to find additional trials.

SELECTION CRITERIA

Randomized controlled trials were considered if they examined fractures, bone mineral density (BMD), or bone turnover in women with hormonal contraceptive use prior to menopause. Studies were excluded if hormones were provided for treatment of a specific condition rather than for contraception. Interventions could include comparisons of a hormonal contraceptive with a placebo or with another hormonal contraceptive. Interventions could also include the provision of a supplement versus a placebo.

DATA COLLECTION AND ANALYSIS

We assessed for inclusion all titles and abstracts identified through the literature searches with no language limitation. The mean difference was computed with 95% confidence interval (CI) using a fixed-effect model.

MAIN RESULTS

We found 13 RCTs, 2 of which used a placebo. No trial had fracture as an outcome but most measured BMD. Combination contraceptives did not appear to affect bone health. Of progestin-only methods, depot medroxyprogesterone acetate (DMPA) was associated with decreased bone mineral density, while results were inconsistent for implants. The two placebo-controlled trials showed BMD increases for DMPA plus estrogen supplement and decreases for DMPA plus placebo.

AUTHORS' CONCLUSIONS

Whether steroidal contraceptives influence fracture risk cannot be determined from existing information. Due to different interventions, no trials could be combined for meta-analysis. Many trials had small numbers of participants and some had large losses to follow up. Health care providers and women should consider the costs and benefits of these effective contraceptives. For example, injectable contraceptives and implants provide effective, long-term birth control yet do not involve a daily regimen. Progestin-only contraceptives are considered appropriate for women who should avoid estrogen due to medical conditions.

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.

Strategies to reverse bone loss in women with functional hypothalamic amenorrhea: a systematic review of the literature

Functional hypothalamic amenorrhea (FHA) impairs the attainment of peak bone mass and as such can increase the risk of fractures later in life. To document available treatment strategies, we conducted a systematic review of the literature. We report that hormonal therapies have limited effectiveness in increasing bone mass, whereas increased caloric intake resulting in weight gain and/or resumption of menses is an essential strategy for restoring bone mass in women with FHA.

INTRODUCTION

Women with functional hypothalamic amenorrhea (FHA) may not achieve peak bone mass (PBM), which increases the risk of stress fractures, and may increase the risk of osteoporotic fractures in later life.

METHODS

To identify effective treatment strategies for women with FHA, we conducted a systematic review of the literature. We included randomized controlled trials (RCTs), cross-sectional studies, and case studies that reported on the effects of pharmacological and non-pharmacological interventions on bone mineral density (BMD) or bone turnover in women with FHA.

RESULTS

Most published studies (n=26) were designed to treat the hormonal abnormalities observed in women with FHA (such as low estrogen, leptin, insulin-like growth factor-1, and DHEA); however none of these treatments demonstrated consistent improvements in BMD. Therapies containing an estrogen given for 8-24 months resulted in variable improvements (1.0-19.0%) in BMD, but failed to restore bone mass to that of age-matched controls. Three studies reported on the use of bisphosphonates (3-12 months) in anorexic women, which appear to have limited effectiveness to improve BMD compared to nutritional treatments. Another three investigations showed no improvements in BMD after androgen therapy (DHEA and testosterone) in anorexic women. In contrast, reports (n=9) describing an increase in caloric intake that results in weight gain and/or the resumption of menses reported a 1.1-16.9% increase in BMD concomitant with an improvement in bone formation and reduction in bone resorption markers.

CONCLUSIONS

Our literature review indicates that the most successful, and indeed essential strategy for improving BMD in women with FHA is to increase caloric intake such that body mass is increased and there is a resumption of menses. Further long-term studies to determine the persistence of this effect and to determine the effects of this and other strategies on fracture risk are needed.

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.

A cross-sectional study of bone turnover markers in healthy premenopausal women

BACKGROUND

Biochemical markers of bone turnover (BTMs) provide useful information in the diagnosis and management of metabolic bone diseases. Currently, there exist few published reference ranges for bone markers in healthy premenopausal women using the newer, automated assays of bone turnover. This cross-sectional study of healthy premenopausal women was performed to determine reference ranges for four different markers of bone turnover and to compare reference ranges in users and non-users of oral contraceptives (OCs).

METHODS

Urinary N-telopeptide of type 1 collagen (NTX) was determined from fasting second morning-void urine of healthy premenopausal women. In addition, fasting serum was collected for determination of C-telopeptide of type I collagen (CTX), bone-specific alkaline phosphatase (bone ALP), and N-terminal propeptide of type 1 procollagen (PINP). Subjects underwent central dual energy X-ray absorptiometry and completed a questionnaire regarding medical history and activities known to affect bone health.

RESULTS

Serum and urine samples were collected from 237 healthy premenopausal women (119 OC users and 118 non-users) between the ages of 28 and 45 years. The mean age of subjects was 37 years, with a mean bone mineral density T-score of -0.1 at the lumbar spine and 0.0 at the total hip. Logarithmic transformation produced normal distributions for all markers but NTX. Mid-95% ranges for each marker were generally consistent with those reported by manufacturers. For each BTM examined, values were skewed toward the lower end of the range. Median NTX levels for OC users and non-users were 16.0 and 29.0 nmol/mmol creatinine, respectively. The mid-95% ranges for NTX in OC users and non-users were 3-60 and 4-64 nmol/mmol creatinine, respectively. Median levels of CTX, bone ALP, and PINP were also lower in OC users than non-users. The mean level of each BTM was significantly lower in OC users than non-users (P<0.01), whereas reference ranges (geometric mean+/-2 SD) were somewhat similar for the two groups.

CONCLUSION

Values obtained from this well-characterized population provide reference ranges for BTMs in healthy premenopausal women. Median and mean BTM levels for OC users were consistently lower compared with non-users; thus, separate reference ranges are required for these two groups of premenopausal women. The relevance of premenopausal reference ranges for postmenopausal women remains uncertain.

Steroidal contraceptives: effect on bone fractures in women

BACKGROUND

Steroidal contraceptive use has been associated with changes in bone mineral density in women. Whether such changes increase the risk of fractures later in life is not clear. However, osteoporosis is a major public health concern. Age-related decline in bone mass increases the risk of fracture, especially of the spine, hip, and wrist. Concern about bone health influences the recommendation and use of these effective contraceptives globally.

OBJECTIVES

To evaluate the effect of using hormonal contraceptives before menopause on the risk of fracture in women

SEARCH STRATEGY

We searched MEDLINE, POPLINE, CENTRAL, EMBASE, and LILACS for studies of fracture or bone health and hormonal contraceptives. We wrote to investigators to find additional trials.

SELECTION CRITERIA

Randomized controlled trials were considered if they examined fractures, bone mineral density (BMD), or bone turnover in women with hormonal contraceptive use prior to menopause. Studies were excluded if hormones were provided for treatment of a specific condition rather than for contraception. Interventions could include comparisons of a hormonal contraceptive with a placebo or with another hormonal contraceptive. Interventions could also include the provision of a supplement versus a placebo.

DATA COLLECTION AND ANALYSIS

We assessed for inclusion all titles and abstracts identified through the literature searches with no language limitation. The weighted mean difference (WMD) was computed with 95% confidence interval (CI) using a fixed-effect model.

MAIN RESULTS

No trial had fracture as an outcome. Combination contraceptives did not appear to affect bone health. Of progestin-only methods, depot medroxyprogesterone acetate (DMPA) was associated with decreased bone mineral density, while results were inconsistent for implants. The two placebo-controlled trials showed BMD increases for DMPA plus estrogen supplement and decreases for DMPA plus placebo.

AUTHORS' CONCLUSIONS

Whether steroidal contraceptives influence fracture risk cannot be determined from existing information. Due to different interventions, no trials could be combined for meta-analysis. Many trials had small numbers of participants and some had large losses to follow up. Health care providers and women should consider the costs and benefits of these effective contraceptives. For example, injectable contraceptives and implants provide effective, long-term birth control yet do not involve a daily regimen. Progestin-only contraceptives are considered appropriate for women who should avoid estrogen due to medical conditions.

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.

High dose estrogen treatment increases bone mineral density in male-to-female transsexuals receiving gonadotropin-releasing hormone agonist in the absence of testosterone

OBJECTIVE

To study the effect of estrogen (E) on the male skeleton in the absence of testosterone (T).

DESIGN

Retrospective analyses of 40 middle-aged transsexuals treated with subcutaneous injections of gonadotropin-releasing hormone agonist every 4 weeks and oral 17-beta-estradiol-valerat 6 mg/day over two years until reassignment surgery.

METHODS

The bone mineral density (BMD) in the femoral neck and lumbar spine (L2-L4) was measured with dual-energy X-ray absorptiometry at the beginning of cross-sex hormone treatment, after 12 and 24 months, and serum T, E, sex hormone-binding globulin (SHBG), calcitonin (CAL), osteocalcin (OSC), and urinary free deoxypyridinoline (DPD) were measured.

RESULTS

After 12 months, a significant increase in BMD in the lumbar spine from 1.2 to 1.234 g/cm2 and after 24 months to 1.274 g/cm2 was observed. There was a significant increase in BMD in the femoral neck area from 1.068 to 1.109 g/cm(2) after 24 months. There was a significant decrease in serum T levels from 18.65 to 0.57 nmol/l after 12 months, and to 0.62 nmol/l after 24 months, a significant increase in SHBG levels from 50.09 to 125 nmol/l after 12 months, and to 130 nmol/l after 24 months, and a significant increase in serum E levels from 73.42 to 881.6 pmol/l after 12 months, and to 923.62 pmol/l after 24 months of cross-sex hormone treatment. Serum levels of CAL, OSC and urinary DPD were unchanged.

CONCLUSION

We conclude that high dose E treatment is able to increase BMD significantly in the femoral neck and lumbar spine independently of serum T levels in middle-aged men. There is no risk of osteoporosis developing in male-to-female transsexuals receiving GnRHa when there is an adequate E substitution.