Short-term effects of a progestational contraceptive drug on food intake, resting energy expenditure, and body weight in young women

Effect of Menstrual Cycle Phase and Hormonal Contraceptives on Resting Metabolic Rate and Body Composition

The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users. This was accomplished during a 5-week training camp involving naturally cycling athletes (n = 11) and HC users (n = 7 subdermal progestin implant, n = 4 combined monophasic oral contraceptive pill, n = 1 injection) from the National Rugby League Indigenous Women's Academy. MC phase was retrospectively confirmed via serum estradiol and progesterone concentrations and a positive ovulation test. HC users had serum estradiol and progesterone concentrations assessed at the time point of testing. Results were analyzed using general linear mixed model. There was no effect of MC phase on absolute RMR (p = .877), relative RMR (p = .957), or dual-energy X-ray absorptiometry body composition estimates (p > .05). There was no effect of HC use on absolute RMR (p = .069), relative RMR (p = .679), or fat mass estimates (p = .766), but HC users had a greater fat-free mass and lean body mass than naturally cycling athletes (p = .028). Our findings suggest that RMR and dual-energy X-ray absorptiometry body composition estimates do not significantly differ due to changes in sex hormones in a group of athletes, and measurements can be compared between MC phases or with HC usage without variations in sex hormones causing additional noise.

Impact of estrogens on resting energy expenditure: A systematic review

The fear of weight gain is one of the main reasons for women not to initiate or to early discontinue hormonal contraception or menopausal hormone therapy. Resting energy expenditure is by far the largest component and the most important determinant of total energy expenditure. Given that low resting energy expenditure is a confirmed predictive factor for weight gain and consecutively for the development of obesity, research into the influence of sex steroids on resting energy expenditure is a particularly exciting area. The objective of this systematic review was to evaluate the effects of medication with natural and synthetic estrogens on resting energy expenditure in healthy normal weight and overweight women. Through complex systematic literature searches, a total of 10 studies were identified that investigated the effects of medication with estrogens on resting energy expenditure. Our results demonstrate that estrogen administration increases resting energy expenditure by up to +208 kcal per day in the context of contraception and by up to +222 kcal per day in the context of menopausal hormone therapy, suggesting a preventive effect of circulating estrogen levels and estrogen administration on weight gain and obesity development.

The Influence of Energy Balance and Availability on Resting Metabolic Rate: Implications for Assessment and Future Research Directions

Resting metabolic rate (RMR) is a significant contributor to an individual's total energy expenditure. As such, RMR plays an important role in body weight regulation across populations ranging from inactive individuals to athletes. In addition, RMR may also be used to screen for low energy availability and energy deficiency in athletes, and thus may be useful in identifying individuals at risk for the deleterious consequences of chronic energy deficiency. Given its importance in both clinical and research settings within the fields of exercise physiology, dietetics, and sports medicine, the valid assessment of RMR is critical. However, factors including varying states of energy balance (both short- and long-term energy deficit or surplus), energy availability, and prior food intake or exercise may influence resulting RMR measures, potentially introducing error into observed values. The purpose of this review is to summarize the relationships between short- and long-term changes in energetic status and resulting RMR measures, consider these findings in the context of relevant recommendations for RMR assessment, and provide suggestions for future research.

Obese Women Have a High Carbohydrate Intake without Changes in the Resting Metabolic Rate in the Luteal Phase

Hormonal changes are caused by the menstrual cycle phases, which influence resting metabolic rate and eating behavior. The aim of the study was to determine resting metabolic rate (RMR) and its association with dietary intake according to the menstrual cycle phase in lean and obese Chilean women. This cross-sectional analytical study included 30 adult women (15 lean and 15 with obesity). Body composition was measured with a tetrapolar bioelectrical impedance meter. Nutritional status was determined by adiposity. A 24-h recall of three nonconsecutive days verifies dietary intake. The RMR was measured by indirect calorimetry. All measurements were performed in both the follicular and luteal phases of the menstrual cycle. Statistical analyses were performed with STATA software at a significance level, which was α = 0.05. The RMR (β = 121.6 kcal/d), temperature (β = 0.36 °C), calorie intake (β = 317.1 kcal/d), and intake of lipids (β = 13.8 g/d) were associated with the luteal phase in lean women. Only extracellular water (β = 1.11%) and carbohydrate consumption (β = 45.2 g/d) were associated in women with obesity. Lean women showed increased RMR, caloric intake, and lipid intake during the luteal phase. For women with obesity, carbohydrate intake increased but not RMR.

Sex Differences in Cognition Across Aging

Sex and gender differences are seen in cognitive disturbances in a variety of neurological and psychiatry diseases. Men are more likely to have cognitive symptoms in schizophrenia whereas women are more likely to have more severe cognitive symptoms with major depressive disorder and Alzheimer's disease. Thus, it is important to understand sex and gender differences in underlying cognitive abilities with and without disease. Sex differences are noted in performance across various cognitive domains - with males typically outperforming females in spatial tasks and females typically outperforming males in verbal tasks. Furthermore, there are striking sex differences in brain networks that are activated during cognitive tasks and in learning strategies. Although rarely studied, there are also sex differences in the trajectory of cognitive aging. It is important to pay attention to these sex differences as they inform researchers of potential differences in resilience to age-related cognitive decline and underlying mechanisms for both healthy and pathological cognitive aging, depending on sex. We review literature on the progressive neurodegenerative disorder, Alzheimer's disease, as an example of pathological cognitive aging in which human females show greater lifetime risk, neuropathology, and cognitive impairment, compared to human males. Not surprisingly, the relationships between sex and cognition, cognitive aging, and Alzheimer's disease are nuanced and multifaceted. As such, this chapter will end with a discussion of lifestyle factors, like education and diet, as modifiable factors that can alter cognitive aging by sex. Understanding how cognition changes across age and contributing factors, like sex differences, will be essential to improving care for older adults.

Novel Equations to Estimate Resting Energy Expenditure during Sitting and Sleeping

INTRODUCTION

Young and early middle-aged office workers spend most of the day sitting or sleeping. Few studies have used a metabolic chamber to report sitting resting energy expenditure (REE) or sleeping metabolic rate (SMR) estimation equations. This study aimed to develop novel equations for estimating sitting REE and SMR, and previously published equations for SMR were compared against measured values.

METHODS

The relationships among sitting REE, SMR, and body composition measured in clinical trials were analyzed. The body composition (fat-free mass [FFM] and fat mass) and energy metabolism of 85 healthy young and early middle-aged Japanese individuals were measured using dual-energy X-ray absorptiometry and a metabolic chamber, respectively. Novel estimate equations were developed using stepwise multiple regression analysis. Estimates of SMR using a new equation and 2 published equations were compared against measured SMR.

RESULTS

The sitting mREE and mSMR were highly correlated (r = 0.756, p < 0.01). The new FFM-based estimate accounted for 50.4% of the variance in measured sitting REE (mREE) and 82.3% of the variance in measured SMR (mSMR). The new body weight-based estimate accounted for 49.3% of the variance in sitting mREE and 82.2% of the variance in mSMR. Compared with mSMR, the SMR estimate using an FFM-based published equation was slightly underestimated.

CONCLUSION

These novel body weight- and FFM-based equations may help estimate sitting REE and SMR in young and early middle-aged adults. Previous SMR estimated FFM-based equations were slightly underestimated against measured SMR; however, we confirmed the previous SMR estimate equations could be useful. This finding suggests that sitting REE and SMR can be easily estimated from individual characteristics and applied in clinical settings.

Effect of menstrual cycle on resting metabolism: A systematic review and meta-analysis

Background

The need to control for the potential influence of menstrual cycle phase on resting metabolism (RMR) places a burden on research participants who must self-report onset of menstruation and researchers who must schedule metabolic testing accordingly.

Purpose

To systematically review and analyze existing research to determine the effect of menstrual cycle on RMR.

Methods

We searched PubMed, CINAHL, MEDLINE, SPORTDiscus, and Scopus databases using the search terms “menstrual cycle and metabolic rate” and “menstrual cycle and energy expenditure.” Eligibility criteria were English language, single-group repeated measures design, and RMR as either a primary or secondary outcome. Risk of bias was assessed based on study sample, measurement, and control of confounders. Differences between the follicular and luteal phases of the menstrual cycle were analyzed using the standardized mean difference in effect size.

Results

Thirty English-language studies published between 1930 and December 2019 were included in the systematic review, and 26 studies involving 318 women were included in the meta-analysis. Overall, there was a small but significant effect favoring increased RMR in the luteal phase (ES = 0.33; 95% CI = 0.17, 0.49, p < 0.001).

Discussion

Limitations include risk of bias regarding measurement of both menstrual cycle and RMR. Sample sizes were small and studies did not report control of potential confounders. Sub-group analysis demonstrated that in more recent studies published since 2000, the effect of menstrual phase was reduced and not statistically significant (ES = 0.23; 95% CI = -0.00, 0.47; p = 0.055). Until larger and better designed studies are available, based on our current findings, researchers should be aware of the potential confounding influence of the menstrual cycle and control for it by testing consistently in one phase of the cycle when measuring RMR in pre-menopausal women.

Effects of low-dose contraceptive pills on the risk factors of cardiovascular diseases among 15-35-year-old women: A retrospective cohort

Background

Cardiovascular diseases could be preventable; as a result, understanding the risk factors was regarded as the major priority for healthcare providers.

Objective

The main objective of this research was to achieve a deeper insight into the effect of long-term use of low-dose oral contraceptive pills (OCP) on the risk factors of cardiovascular diseases.

Materials and Methods

This research was a retrospective cohort conducted (historical and prospectively) conducted on 100 women with normal menstrual cycles aged 15 to 35 yr, who were referred to the healthcare centers in Yazd, Iran. The participants were categorized into two groups: The OCP group was consuming the pills for 0-3, 4-23, and 24-36 months, and the non-OCP group. Participants were followed up for a minimum of 3 months and a maximum of six months.

Results

The highest level of low-density lipoprotein (LDL), homocysteine, cholesterol, triglyceride levels, and systolic blood pressure was observed in the OCP group in the duration of 24 to 36 months. The Tukey's test demonstrated that there were comprehensible differences in the LDL (p = 0.01), cholesterol (p = 0.01), triglyceride (p < 0.001), and homocysteine levels (p < 0.001), also systolic blood pressure (p = 0.04).

Conclusion

It was realized that the long-term consumption of low-dose OCP can augment the incidence of some risk factors (systolic blood pressure, homocysteine levels, cholesterol, LDL-c, and triglyceride) and lead to developing cardiovascular diseases amongst the healthy women.

Gender-specific considerations in physical activity, thermogenesis and fat oxidation: implications for obesity management

With current 'one-size-fits-all' obesity prevention and management strategies proving largely ineffective, the focus has shifted towards a more tailored, individualized approach. However, investigation of the mechanisms underlying inter-individual variability in metabolic profile and response to intervention often yield conflicting results. Indeed, it is perhaps surprising that despite at least a century of recognition that sex hormones influence metabolism, firm conclusions regarding the effects of the menstrual cycle, hormonal contraception and menopause on many aspects of energy expenditure and substrate utilization remain to be drawn. In this review, we examine current evidence relating to gender-specific considerations in the promotion of physical activity, thermogenesis and fat oxidation for body-weight regulation, including the relationship between sex hormone status and non-exercise activity thermogenesis - an energy expenditure compartment that is often overlooked in favour of traditional exercise/sport physical activities yet presents a viable target in the search for effective weight management.

Dietary intake and eating behavior in depot medroxyprogesterone acetate users: a systematic review

Because of weight gain, women often discontinue hormonal contraception, especially depot medroxyprogesterone acetate (DMPA). Our objective was to conduct a systematic review of studies describing dietary intake or eating behavior in DMPA users to understand whether the use of DMPA is associated with changes in dietary habits and behaviors leading to weight gain. We searched the PubMed, POPLINE, CENTRAL Cochrane, Web of Science, and EMBASE databases for reports published in English between 1980 and 2017 examining dietary intake or eating behavior in healthy women in reproductive age and adolescents using DMPA (150 mg/mL). Of the 749 publications screened, we excluded 742 due to duplicates (96), not addressing the key research question (638), not reporting dietary intake data (4), and not evaluating the relationship of body weight and dietary or eating behaviors (4). We identified seven relevant studies, including one randomized placebo-controlled trial, one non-randomized paired clinical trial, and five cohort studies. The randomized trial found no association and the other reports were inconsistent. Findings varied from no change in dietary intake or eating behavior with DMPA use to increased appetite in the first six months of DMPA use. Few studies report dietary intake and eating behavior in DMPA users and the available data are insufficient to conclude whether DMPA use is associated with changes in dietary habits or behavior leading to weight gain.

Ovarian hormones and obesity

BACKGROUND

Obesity is caused by an imbalance between energy intake, i.e. eating and energy expenditure (EE). Severe obesity is more prevalent in women than men worldwide, and obesity pathophysiology and the resultant obesity-related disease risks differ in women and men. The underlying mechanisms are largely unknown. Pre-clinical and clinical research indicate that ovarian hormones may play a major role.

OBJECTIVE AND RATIONALE

We systematically reviewed the clinical and pre-clinical literature on the effects of ovarian hormones on the physiology of adipose tissue (AT) and the regulation of AT mass by energy intake and EE.

SEARCH METHODS

Articles in English indexed in PubMed through January 2016 were searched using keywords related to: (i) reproductive hormones, (ii) weight regulation and (iii) central nervous system. We sought to identify emerging research foci with clinical translational potential rather than to provide a comprehensive review.

OUTCOMES

We find that estrogens play a leading role in the causes and consequences of female obesity. With respect to adiposity, estrogens synergize with AT genes to increase gluteofemoral subcutaneous AT mass and decrease central AT mass in reproductive-age women, which leads to protective cardiometabolic effects. Loss of estrogens after menopause, independent of aging, increases total AT mass and decreases lean body mass, so that there is little net effect on body weight. Menopause also partially reverses women's protective AT distribution. These effects can be counteracted by estrogen treatment. With respect to eating, increasing estrogen levels progressively decrease eating during the follicular and peri-ovulatory phases of the menstrual cycle. Progestin levels are associated with eating during the luteal phase, but there does not appear to be a causal relationship. Progestins may increase binge eating and eating stimulated by negative emotional states during the luteal phase. Pre-clinical research indicates that one mechanism for the pre-ovulatory decrease in eating is a central action of estrogens to increase the satiating potency of the gastrointestinal hormone cholecystokinin. Another mechanism involves a decrease in the preference for sweet foods during the follicular phase. Genetic defects in brain α-melanocycte-stimulating hormone-melanocortin receptor (melanocortin 4 receptor, MC4R) signaling lead to a syndrome of overeating and obesity that is particularly pronounced in women and in female animals. The syndrome appears around puberty in mice with genetic deletions of MC4R, suggesting a role of ovarian hormones. Emerging functional brain-imaging data indicates that fluctuations in ovarian hormones affect eating by influencing striatal dopaminergic processing of flavor hedonics and lateral prefrontal cortex processing of cognitive inhibitory controls of eating. There is a dearth of research on the neuroendocrine control of eating after menopause. There is also comparatively little research on the effects of ovarian hormones on EE, although changes in ovarian hormone levels during the menstrual cycle do affect resting EE.

WIDER IMPLICATIONS

The markedly greater obesity burden in women makes understanding the diverse effects of ovarian hormones on eating, EE and body adiposity urgent research challenges. A variety of research modalities can be used to investigate these effects in women, and most of the mechanisms reviewed are accessible in animal models. Therefore, human and translational research on the roles of ovarian hormones in women's obesity and its causes should be intensified to gain further mechanistic insights that may ultimately be translated into novel anti-obesity therapies and thereby improve women's health.

Ovarian hormone fluctuations predict within-cycle shifts in women's food intake

What role do ovarian hormones play in modulating day-to-day shifts in women's motivational priorities? In many nonhuman mammals, estradiol causes drops in feeding and foraging, progesterone reverses this effect, and the two hormones in combination produce cycle phase shifts characterized by lower food intake near ovulation when sexual receptivity is at its peak. Hormonal predictors of within-cycle shifts in women's total food intake have not been previously tested. Here, in a study with both daily hormone measures and self-reported food intake, we found that within-cycle fluctuations in estradiol negatively predicted shifts in food intake, progesterone fluctuations positively predicted them, and the two hormones together statistically mediated a significant peri-ovulatory drop in eating. These patterns are precisely opposite to those previously reported for sexual desire from this same sample (i.e. positive and negative effects of estradiol and progesterone, respectively, on desire). To more precisely test endocrine regulation of tradeoffs between sexual and eating motivation, a difference score for the daily standardized values of the sexual desire and food intake variables was created. Fluctuations in estradiol and progesterone were oppositely associated with shifts in this difference score, supporting hormone modulation of tradeoffs between alternative motivational priorities. These tradeoffs were especially pronounced during the fertile window of the menstrual cycle on days when conception was possible, consistent with the hormone effects functioning to shift motivational salience between feeding and mating depending on within-cycle changes in fecundity. The findings provide direct evidence that phylogenetically conserved endocrine signals regulate daily shifts in human motivational priorities.

Body composition, resting energy expenditure and inflammatory markers: impact in users of depot medroxyprogesterone acetate after 12 months follow-up

OBJECTIVE

The aim of this study was to evaluate for 12 months the changes of body weight using Depot Medroxyprogesterone Acetate (DMPA) and if these changes are related to inflammatory markers.

SUBJECTS AND METHODS

Twenty women of childbearing age who chose the DMPA, without previous use of this method, BMI < 30 kg/m2, and 17 women using IUD TCu 380A, participated in the study. At the baseline and after one year, changes in weight gain, body composition by the bioimpedance electric method, resting energy expenditure (REE) by the indirect calorimetry method, inflammatory markers and HOMA-IR were assessed.

RESULTS

After 12 months of evaluation, we could observe a significant increase in the DMPA group in weight (3,01 kg) and BMI, while the IUD group's only significant increase was observed in the BMI. Relative to REE there was an increase of basal metabolic rate (BMR) in both groups after one year. The sub-group DMPA that gained < 3 kg had increased significant weight, BMI and body surface (BS) with respiratory quotient (RQ) reduction, while the sub-group that gained ≥ 3 kg had a significant increase in weight, BMI, BS, fat-free mass, fat mass, BMR, Leptin, HOMA-IR and waist circumference, with RQ significantly reduced.

CONCLUSION

Our study found significant changes in weight, body composition and metabolic profile of the population studied in the first 12 months of contraceptive use. These changes mainly increased body weight, leptin levels and HOMA-IR which can contribute to the development of some chronic complications, including obesity, insulin resistance and diabetes mellitus.

Binge eating and biochemical markers of appetite in new users of the contraceptive depot medroxyprogesterone acetate

PURPOSE

Weight gain has been cited by women as one of the main reasons for discontinuation of the contraceptive depot medroxyprogesterone acetate (DMPA). This study aimed to evaluate binge eating and the biochemical markers of appetite in new DMPA users.

METHODS

In this prospective non randomized study with adult healthy women, twenty-eight users of DMPA and twenty-five users of a copper intrauterine device (IUD) were paired for age (±1 year) and body mass index (BMI) (±1 kg/m²). We evaluated binge eating using the Binge Eating Scale (BES), the serum levels of neuropeptide Y, leptin and adiponectin, and the BMI at baseline and after 12 months in both groups. For statistical analysis was used ANOVA for to compare the means of the repeated measurements.

RESULTS

Mean age was 29.6 and 28.6 years and BMI was 23.9 and 24.5 kg/m² for the DMPA and IUD groups, respectively. After 12 months, the frequency of the scores of binge eating remained low in both groups. There were no significant differences between the groups at 12 months with respect to BMI, levels of NPY, leptin, adiponectin, and BES scores.

CONCLUSIONS

Healthy adult women did not present with central stimulation of appetite or binge eating disorder in their first year after starting use of DMPA. This study reinforces the use of the contraceptive DPMA and the need for guidance related to living a healthy lifestyle for women who attribute the increase of body weight to the use of the method.

The Effect of Depo Medroxyprogesterone Acetate (DMPA) on Cerebral Food Motivation Centers: A Pilot Study using Functional Magnetic Resonance Imaging

OBJECTIVE

The primary objective is to examine activation of food motivation centers in the brain before and 8 weeks after depo medroxyprogesterone acetate (DMPA) administration.

STUDY DESIGN

This prospective experimental pilot study examined the effects of DMPA on food motivation centers utilizing functional magnetic resonance imaging (fMRI) in eight nonobese, ovulatory subjects. fMRI blood oxygen level dependent (BOLD) signal was measured using a 3-Tesla Scanner while participants viewed images of high-calorie foods, low-calorie foods and nonfood objects. fMRI scans were performed at baseline and 8 weeks after participants received one intramuscular dose of DMPA 150 mg. fMRI data were analyzed using the FMRIB Software Library. Changes in adiposity and circulating leptin and ghrelin levels were also measured.

RESULTS

There was a greater BOLD signal response to food cues in brain regions associated with food motivation (anterior cingulate gyrus, orbitofrontal cortex) 8 weeks after DMPA administration compared to baseline (z>2.3, p<.05 whole-brain analysis clustered corrected). No statistically significant change was detected in circulating leptin or ghrelin levels or fat mass 8 weeks after DMPA administration.

CONCLUSION

Analysis of differences in food motivation may guide the development of interventions to prevent weight gain in DMPA users.

IMPLICATIONS

These data support a neural origin as one of the mechanisms underlying weight gain in DMPA users and may guide future research examining weight gain and contraception.

The impact of short-term depot-medroxyprogesterone acetate treatment on resting metabolic rate

OBJECTIVE

This study examines the effect of a progestogen (depot-medroxyprogesterone acetate, DMPA) on resting metabolic rate (RMR) in a cohort of young, normal-weight healthy women. We hypothesize an increase in RMR and nonshivering thermogenesis (NST) resulting in increased body temperature by DMPA.

STUDY DESIGN

We performed a prospective cohort study in 13 subjects tested at baseline, 3 weeks and 9 weeks after 150 mg intramuscular DMPA administration. RMR was determined with indirect calorimetry. Secondary endpoints included changes in body mass index (BMI), body composition, temperature and serum levels of estradiol (E2), luteinizing hormone (LH), progesterone and MPA.

RESULTS

The percent change in RMR from baseline to week 3 (9%) was significantly higher than the percent change from baseline to week 9 (1.6%) (p=.045). The greatest percent change from baseline to week 3 compared to baseline to week 9 was seen in women initiating DMPA in the luteal phase of the cycle. Hypothalamic-pituitary-ovarian axis was evident by decreases in E2, LH and progesterone. DMPA resulted in increased body temperature with a significant correlation between the change in body temperature and the change in RMR. No change in body composition was seen.

CONCLUSIONS

RMR and NST increased in young healthy women with normal BMI 3 weeks after receiving the initial dose of 150 mg DMPA for contraception. The effect was augmented when the drug was administered during the luteal phase of the menstrual cycle.

IMPLICATION

DMPA increases RMR and thermogenesis independent of changes in body mass. An increase in weight with chronic DMPA may result from a combination of hyperphagia and abnormal NST in predisposed individuals.

Gasto energético e medidas antropométricas de novas usuárias do contraceptivo injetável trimestral de acetato de medroxiprogesterona de depósito

Objetivo:Avaliar o gasto energético e as medidas antropométricas de mulheres durante o primeiro ano de uso do método contraceptivo de acetato de medroxiprogesterona de depósito.Métodos:Estudo prospectivo com grupo de comparação. Foram incluídas mulheres saudáveis, não obesas, nunca usuárias de acetato de medroxiprogesterona de depósito e sem antecedentes que pudessem contribuir para a variação do peso corporal; foram distribuídas em dois grupos, 28 usuárias de acetato de medroxiprogesterona e 24 usuárias de dispositivo intrauterino de cobre, pareadas por idade (±1 ano) e índice de massa corporal (kg/m2). As variáveis estudadas foram sociodemográficas (idade, etnia, tabagismo, etilismo, atividade física, classe econômica e escolaridade), peso (kg), índice de massa corporal, gasto energético basal e total, medidas de circunferência de cintura e quadril (cm) e relação cintura-quadril.Resultados:A idade das mulheres variou de 20-39 anos. As médias de idade/índice de massa corporal foram 29,6 (DP=±5,2) anos/23,9 (±3,6 kg/m2), no grupo de acetato de medroxiprogesterona de depósito, e de 28,6 (DP=±5,2) anos/ 24,5 (±2,7 kg/m2), no grupo de dispositivo intrauterino de cobre. Após análise de variância para medidas repetidas, as usuárias de acetato de medroxiprogesterona de depósito apresentaram ganho de 2,2 kg no peso corporal e de -0,2 kg no grupo do dispositivo intrauterino de cobre, sem diferença estatisticamente significativa entre eles. Não houve discrepância nas demais variáveis estudadas.Conclusão:Mulheres saudáveis e jovens não apresentaram mudança no peso, nas medidas e nos gastos energéticos durante o primeiro ano de uso do contraceptivo acetato de medroxiprogesterona. A orientação em relação aos hábitos saudáveis de vida e o monitoramento de medidas são importantes para o controle do peso corporal em usuárias de métodos contraceptivos.

Regulation of Estrogen Receptor α Expression in the Hypothalamus by Sex Steroids: Implication in the Regulation of Energy Homeostasis

Sex differences exist in the complex regulation of energy homeostasis that utilizes central and peripheral systems. It is widely accepted that sex steroids, especially estrogens, are important physiological and pathological components in this sex-specific regulation. Estrogens exert their biological functions via estrogen receptors (ERs). ERα, a classic nuclear receptor, contributes to metabolic regulation and sexual behavior more than other ER subtypes. Physiological and molecular studies have identified multiple ERα-rich nuclei in the hypothalamus of the central nervous system (CNS) as sites of actions that mediate effects of estrogens. Much of our understanding of ERα regulation has been obtained using transgenic models such as ERα global or nuclei-specific knockout mice. A fundamental question concerning how ERα is regulated in wild-type animals, including humans, in response to alterations in steroid hormone levels, due to experimental manipulation (i.e., castration and hormone replacement) or physiological stages (i.e., puberty, pregnancy, and menopause), lacks consistent answers. This review discusses how different sex hormones affect ERα expression in the hypothalamus. This information will contribute to the knowledge of estrogen action in the CNS, further our understanding of discrepancies in correlation of altered sex hormone levels with metabolic disturbances when comparing both sexes, and improve health issues in postmenopausal women.

The role of reproductive hormones in the development and maintenance of eating disorders

Much remains to be understood about the etiology of eating disorders. There is substantial evidence that reproductive hormones, specifically estrogens, play a direct role in normal food intake. Evidence is increasing that the reproductive hormones play a role in the abnormal food intake associated with eating disorders. For example, there is an inverse association between estradiol and eating disorder symptoms. Preliminary studies also suggest that hormone augmentation may be a beneficial adjunct to the standard treatment of choice for eating disorders. However, research is limited, so definitive conclusions about the benefit of hormone augmentation in treatment cannot be drawn. Future research, with a focus on translational studies, should continue to explore the role of reproductive hormones in the vulnerability to and maintenance of eating disorders.

Oestradiol differentially influences feeding behaviour depending on diet composition in female rhesus monkeys

In females, cyclical changes in the ovarian hormone oestradiol are known to modulate feeding behaviour. However, what is less clear is how these behavioural effects of oestradiol are modified by the macronutrient content of a diet. In the present study, we report data showing that oestradiol treatment results in both significantly smaller meals and a reduced total calorie intake in ovariectomised, socially-housed female rhesus macaques when only chow diet is available. Conversely, during a choice dietary condition where both palatable and chow options are available, oestradiol treatment had no observable, attenuating effect on calorie intake. During this choice dietary phase, all animals consumed more of the palatable diet than chow diet; however, oestradiol treatment appeared to further increase preference for the palatable diet. Finally, oestradiol treatment increased snacking behaviour (i.e. the consumption of calories outside of empirically defined meals), regardless of diet condition. These findings illustrate how oestradiol differentially influences feeding behaviour depending on the dietary environment and provides a framework in which we can begin to examine the mechanisms underlying these observed changes.

Sex differences in the physiology of eating

Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating.

Progestin-only contraceptives: effects on weight

BACKGROUND

Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. Many POCs are long-acting, cost-effective methods of preventing pregnancy. However, concern about weight gain can deter the initiation of contraceptives and cause early discontinuation among users.

OBJECTIVES

The primary objective was to evaluate the association between progestin-only contraceptive use and changes in body weight.

SEARCH METHODS

Through May 2013, we searched MEDLINE, CENTRAL, POPLINE, LILACS, ClinicalTrials.gov, and ICTRP. The 2010 search also included EMBASE. For the initial review, we contacted investigators to identify other trials.

SELECTION CRITERIA

All comparative studies were eligible that examined a POC versus another contraceptive method or no contraceptive. The primary outcome was mean change in body weight or mean change in body composition. We also considered the dichotomous outcome of loss or gain of a specified amount of weight.

DATA COLLECTION AND ANALYSIS

Two authors extracted the data. We computed the mean difference (MD) with 95% confidence interval (CI) for continuous variables. For dichotomous outcomes, the Mantel-Haenszel odds ratio (OR) with 95% CI was calculated.

MAIN RESULTS

We found 16 studies; one examined progestin-only pills, one studied the levonorgestrel-releasing intrauterine system (LNG-IUS), four examined an implant, and 10 focused on depot medroxyprogesterone acetate (DMPA). Outcomes examined were changes in body weight only (14 studies), changes in both body weight and body composition (1 study), and changes in body composition only (1 study). We did not conduct meta-analysis due to the various contraceptive methods and weight change measures.Comparison groups did not differ significantly for weight change in 12 studies. However, three studies showed weight change differences for POC users compared to women not using a hormonal method. In one study, weight gain (kg) was greater for the DMPA group than the group using a non-hormonal IUD in years one through three [(MD 2.28; 95% CI 1.79 to 2.77), (MD 2.71, 95% CI 2.12 to 3.30), and (MD 3.17; 95% CI 2.51 to 3.83), respectively]. The differences were notable within the normal weight and overweight subgroups. Two implant studies also showed differences in weight change. The implant group (six-capsule) had greater weight gain (kg) compared to the group using a non-hormonal IUD in both studies [(MD 0.47 (95% CI 0.29 to 0.65); (MD 1.10; 95% CI 0.36 to 1.84)]. In one of those studies, the implant group also had greater weight gain than a group using a barrier method or no contraceptive (MD 0.74; 95% CI 0.52 to 0.96).The two studies that assessed body composition change showed differences between POC users and women not using a hormonal method. Adolescents using DMPA had a greater increase in body fat (%) compared to a group not using a hormonal method (MD 11.00; 95% CI 2.64 to 19.36). The DMPA group also had a greater decrease in lean body mass (%) (MD -4.00; 95% CI -6.93 to -1.07). The other study reported differences between an LNG-IUS group and a non-hormonal IUD group in percent change in body fat mass (2.5% versus -1.3%, respectively; reported P value = 0.029) and percent change in lean body mass (-1.4% versus 1.0%, respectively; reported P value = 0.027).

AUTHORS' CONCLUSIONS

The overall quality of evidence was moderate to low, given that the studies were evenly divided across the evidence quality groups (high, moderate, low, or very low quality). We found limited evidence of weight gain when using POCs. Mean gain was less than 2 kg for most studies up to 12 months. Weight change for the POC group generally did not differ significantly from that of the comparison group using another contraceptive. Two studies that assessed body composition showed that POC users had greater increases in body fat and decreases in lean body mass compared to users of non-hormonal methods. Appropriate counseling about typical weight gain may help reduce discontinuation of contraceptives due to perceptions of weight gain.

Coadministration of glucagon-like peptide-1 during glucagon infusion in humans results in increased energy expenditure and amelioration of hyperglycemia

Glucagon and glucagon-like peptide (GLP)-1 are the primary products of proglucagon processing from the pancreas and gut, respectively. Giving dual agonists with glucagon and GLP-1 activity to diabetic, obese mice causes enhanced weight loss and improves glucose tolerance by reduction of food intake and by increase in energy expenditure (EE). We aimed to observe the effect of a combination of glucagon and GLP-1 on resting EE and glycemia in healthy human volunteers. In a randomized, double-blinded crossover study, 10 overweight or obese volunteers without diabetes received placebo infusion, GLP-1 alone, glucagon alone, and GLP-1 plus glucagon simultaneously. Resting EE--measured using indirect calorimetry--was not affected by GLP-1 infusion but rose significantly with glucagon alone and to a similar degree with glucagon and GLP-1 together. Glucagon infusion was accompanied by a rise in plasma glucose levels, but addition of GLP-1 to glucagon rapidly reduced this excursion, due to a synergistic insulinotropic effect. The data indicate that drugs with glucagon and GLP-1 agonist activity may represent a useful treatment for type 2 diabetes and obesity. Long-term studies are required to demonstrate that this combination will reduce weight and improve glycemia in patients.

Progestin-only contraceptives: effects on weight

BACKGROUND

Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. Many POCs are long-acting, cost-effective methods of preventing pregnancy. However, concern about weight gain can deter the initiation of contraceptives and cause early discontinuation among users.

OBJECTIVES

The primary objective was to evaluate the association between progestin-only contraceptive use and changes in body weight.

SEARCH STRATEGY

We searched MEDLINE, CENTRAL, POPLINE, EMBASE, LILACS, ClinicalTrials.gov, and ICTRP, and contacted investigators to identify other trials.

SELECTION CRITERIA

All comparative studies were eligible that examined a POC versus another method or no contraceptive. The primary outcome was mean change in body weight or body composition.

DATA COLLECTION AND ANALYSIS

Two authors extracted the data. We computed the mean difference with 95% confidence interval (CI) for continuous variables and odds ratio with 95% CI for dichotomous variables.

MAIN RESULTS

We did not conduct meta-analysis due to the various contraceptive methods and weight change measures. Fifteen studies examined progestin-only pills (N=1), Norplant (N=4), and depot medroxyprogesterone acetate (DMPA) (N=10). Comparison groups were similar for weight change in 11 studies. Four studies showed differences in weight or body composition change for POCs compared to no hormonal method. Adolescents using DMPA had a greater increase in body fat (%) versus a group using no hormonal method (mean difference 11.00; 95% CI 2.64 to 19.36). The DMPA group also had a greater decrease in lean body mass (%) (mean difference -4.00; 95% CI -6.93 to -1.07). In another study, weight gain (kg) was greater for the DMPA group than an IUD group (mean difference 2.28, 2.71, 3.17, respectively). The differences were notable within the normal weight and overweight subgroups. One study showed the Norplant (six-capsule) group had greater weight gain (kg) than a non-hormonal IUD group (mean difference 0.47 (95% CI 0.29 to 0.65) and a group using non-hormonal or no method (mean difference 0.74; 95% CI 0.52 to 0.96). Another study also showed a Norplant group also had greater weight gain (kg) than an IUD group (mean difference 1.10; 95% CI 0.36 to 1.84).

AUTHORS' CONCLUSIONS

We found little evidence of weight gain when using POCs. Mean gain was less than 2 kg for most studies up to 12 months, and usually similar for the comparison group using another contraceptive. Appropriate counseling about typical weight gain may help reduce discontinuation of contraceptives due to perceptions of weight gain.

Nutrition and human health from a sex-gender perspective

Nutrition exerts a life-long impact on human health, and the interaction between nutrition and health has been known for centuries. The recent literature has suggested that nutrition could differently influence the health of male and female individuals. Until the last decade of the 20th century, research on women has been neglected, and the results obtained in men have been directly translated to women in both the medicine and nutrition fields. Consequently, most modern guidelines are based on studies predominantly conducted on men. However, there are many sex-gender differences that are the result of multifactorial inputs, including gene repertoires, sex steroid hormones, and environmental factors (e.g., food components). The effects of these different inputs in male and female physiology will be different in different periods of ontogenetic development as well as during pregnancy and the ovarian cycle in females, which are also age dependent. As a result, different strategies have evolved to maintain male and female body homeostasis, which, in turn, implies that there are important differences in the bioavailability, metabolism, distribution, and elimination of foods and beverages in males and females. This article will review some of these differences underlying the impact of food components on the risk of developing diseases from a sex-gender perspective.

Eating disorder pathology and menstrual cycle fluctuations in eating variables in oral contraceptive users and non-users

Food intake and food cravings fluctuate across the menstrual cycle in women who are not using oral contraceptives (OCs), however less is known about cyclical variations in eating variables in women using OCs. Furthermore, few studies have examined the relationship between eating disorder pathology and menstrual cycle fluctuations in eating behaviors. In the present study, we examined self-report, retrospective ratings of food cravings intensity, hunger level, and amount eaten across the menstrual cycle in 67 non-OC users and across exogenous hormone regimens in 81 OC users. We also investigated the relationship between eating disorder pathology and cyclical fluctuations in eating variables. The results indicated that OC users and non-OC users report similar levels of food cravings and amount eaten across cycle phases, with food cravings and reported amount eaten elevated during the week prior to menses/hormone withdrawal bleeding and during the week of menses/hormone withdrawal bleeding. However, OC users reported elevated hunger during both the week prior to hormone withdrawal bleeding and during hormone withdrawal bleeding, whereas non-OC users reported an elevation in hunger level only during the week prior to menses. Fear of fatness and other eating disorder pathology variables were significantly associated with increases in food cravings, hunger level and reported amount eaten the week prior to menses in non-OC users, but not in OC users. These findings suggest that future studies should examine the potential role of menstrual cycle-related fluctuations in eating variables on the development of eating disorders.

[Influence of premenstrual syndrome and oral contraceptive effects on food choice during the follicular and luteal phase of the menstrual cycle]

BACKGROUND AND OBJECTIVE

Food intake and motivation for food varies according to the phase of the menstrual cycle. These changes seem to be more marked in women with premenstrual syndrome (PMS) and may be modified by the use of oral contraceptives (OC). This study examined the effect of menstrual cycle, PMS and OC use on the intake and hedonic rating of sweet and savory snack foods.

MATERIAL AND METHODS

Fifty-five women were recruited and assigned to either a PMS group or a control group. In addition, based on OC use, the women were assigned to an OC-user or non-user group. During the luteal and follicular phases, the participants were asked to consume and rate sweet and savory snacks.

RESULTS

The luteal phase induced greater caloric intake from sweet foods. PMS sufferers did not consume significantly more calories in either phase. There was a significant interaction between phase, flavor, PMS status and OC use. OC users consumed more calories from sweet foods in the follicular phase.

CONCLUSIONS

Food intake is increased in the luteal phase. This effect was modulated by both PMS and OC use. OC use seems to eliminate cyclic fluctuations in caloric intake.

Long-acting contraceptives in adolescents

PURPOSE OF REVIEW

To help clinicians guide adolescent patients to sound choices regarding long-acting contraceptives. The safety, side effects and non-contraceptive benefits of injectable, implantable and intrauterine contraception are detailed.

RECENT FINDINGS

The use of depot medroxyprogesterone acetate contraceptive injections has been associated with declines in teenage pregnancies in the United States. Although the US Food and Drug Administration has placed a black box warning concerning skeletal health and depot medroxyprogesterone acetate, data in adolescents confirm that declines in bone mineral density with depot medroxyprogesterone acetate are fully reversible. Concerns regarding skeletal health should not restrict the initiation or continuation of depot medroxyprogesterone acetate in adolescents. A highly effective, convenient, and easy to insert/remove single rod progestin-only contraceptive implant (Implanon) is now available in the United States. Although not widely used in adolescents, intrauterine devices offer selected adolescents convenient, highly effective, safe birth control. Use of the progestin-releasing intrauterine device (Mirena) is also associated with important non-contraceptive benefits.

SUMMARY

The efficacy and convenience associated with long-acting contraceptives make them indispensable for adolescent patients. This review will help clinicians guide teenage patients towards sound contraceptive choices and the successful long-term use of injectable, implantable and intrauterine methods of birth control.

Impact of the menstrual cycle on determinants of energy balance: a putative role in weight loss attempts

Women's weight and body composition is significantly influenced by the female sex-steroid hormones. Levels of these hormones fluctuate in a defined manner throughout the menstrual cycle and interact to modulate energy homeostasis. This paper reviews the scientific literature on the relationship between hormonal changes across the menstrual cycle and components of energy balance, with the aim of clarifying whether this influences weight loss in women. In the luteal phase of the menstrual cycle it appears that women's energy intake and energy expenditure are increased and they experience more frequent cravings for foods, particularly those high in carbohydrate and fat, than during the follicular phase. This suggests that the potential of the underlying physiology related to each phase of the menstrual cycle may be worth considering as an element in strategies to optimize weight loss. Studies are needed to assess the weight loss outcome of tailoring dietary recommendations and the degree of energy restriction to each menstrual phase throughout a weight management program, taking these preliminary findings into account.

Changes in weight with depot medroxyprogesterone acetate subcutaneous injection 104 mg/0.65 mL

INTRODUCTION

The study was conducted to assess the impact of depot medroxyprogesterone acetate subcutaneous injection 104 mg/0.65 mL (DMPA-SC 104) on body weight.

METHODS

Changes in weight from pretreatment were analyzed using data from two 1-year, noncomparative trials of DMPA-SC 104 (North/South American, N=722; European/Asian, N=1065) and a 3-year, randomized study (SC/IM) comparing DMPA-SC 104 (N=266) with the DMPA intramuscular injection 150 mg/mL (DMPA-IM 150). For each study, additional analyses were conducted for changes in body weight by age (<25, 25 to 35 and >35 years) and body mass index (BMI) (<or=25, >25 to <or=30 and >30 kg/m2) subgroups.

RESULTS

In both 1-year trials, the mean (+/-SD) weight gain at month 12 was <2 kg [1.7 kg (+/-4.5 SD) in the Americas trial and 1.4 kg (+/-3.6 SD) in the Europe/Asia trial]. In the SC/IM trial, mean weight changes were similar between DMPA-SC 104 and DMPA-IM 150 groups, with mean (+/-SD) gains at month 36 of 4.5+/-8.5 and 5.8+/-8.7 kg, respectively. Similar differences in weight gain were observed by age or baseline BMI in all studies.

CONCLUSION

DMPA-SC 104 was associated with modest weight gain in most women.

Modulation of appetite by gonadal steroid hormones

Several sex differences in eating, their control by gonadal steroid hormones and their peripheral and central mediating mechanisms are reviewed. Adult female rats and mice as well as women eat less during the peri-ovulatory phase of the ovarian cycle (estrus in rats and mice) than other phases, an effect under the control of cyclic changes in estradiol secretion. Women also appear to eat more sweets during the luteal phase of the cycle than other phases, possibly due to simultaneous increases in estradiol and progesterone. In rats and mice, gonadectomy reveals further sex differences: orchiectomy decreases food intake by decreasing meal frequency and ovariectomy increases food intake by increasing meal size. These changes are reversed by testosterone and estradiol treatment, respectively. A variety of peripheral feedback controls of eating, including ghrelin, cholecystokinin (CCK), glucagon, hepatic fatty acid oxidation, insulin and leptin, has been shown to be estradiol-sensitive under at least some conditions and may mediate the estrogenic inhibition of eating. Of these, most progress has been made in the case of CCK. Neurons expressing estrogen receptor-alpha in the nucleus tractus solitarius of the brainstem appear to increase their sensitivity to CCK-induced vagal afferent input so as to lead to an increase in the satiating potency of CCK, and consequently decreased food intake, during the peri-ovulatory period in rats. Central serotonergic mechanisms also appear to be part of the effect of estradiol on eating. The physiological roles of other peripheral feedback controls of eating and their central mediators remain to be established.

Validation of three predictive equations for basal metabolic rate in adults

Objective

To cross-validate three predictive set of equations for basal metabolic rate (BMR) developed by Schofield (Schofield database), Henry (Oxford database) and Cole (Oxford database) using mean values for age, weight, height and BMR of published studies.

Design

Literature review of studies published from 1985 to March 2002.

Setting

All studies selected used appropriate methods and followed conditions that met the criteria established for basal metabolism, were performed in healthy adults, and were not part of the Schofield or Oxford database.

Subjects

A total of 261 groups of men and women from 175 studies were selected and categorised in three age groups (18.5–29.9, 30.0–59.9, ≥60 years old) and three body mass index (BMI) groups (normal weight, overweight and obese).

Results

Linear regression and concordance correlation analysis showed that the three sets of equations had the same association and agreement with measured BMR, across gender, age, and BMI groups. The agreement of all equations was moderate for men and poor for women. The lowest mean squared prediction errors (MSPRs) were given by Henry equations in men and Cole equations in women. Henry and Cole equations gave lower values than Schofield equations, except for men over 60 years of age. Henry equations were the most accurate in men. None of the three equations performed consistently better in women.

Conclusion

These results support the use of Henry equations in men with a wide range of age and BMI. None of the proposed predictive equations seem to be appropriate to estimate BMR in women.

Hormonal contraception in adolescents: special considerations

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

Bone mineral density in women aged 25–35 years receiving depot medroxyprogesterone acetate: recovery following discontinuation

INTRODUCTION

This 7-year, prospective, matched-cohort, clinical study evaluated the effects of intramuscular depot medroxyprogesterone acetate (DMPA) (150 mg/mL) on bone mineral density (BMD) in women aged 25-35 years.

METHODS

Bone mineral density changes in new DMPA-IM users (n=248) were compared with those in women using nonhormonal contraception (n=360) for up to 240 weeks of treatment and 96 weeks of posttreatment follow-up (in subjects receiving >or=1 dose).

RESULTS

At week 240 of treatment, mean percentage changes from baseline in DMPA-IM vs. nonhormonal subjects were: -5.16% (n=21) vs. +0.19% (n=65), total hip (p<.001); -5.38% (n=33) vs. +0.43% (n=105), lumbar spine (p<.001). At week 96 posttreatment, these values were: -0.20% (n=25) vs. +0.84% (n=43), total hip (p=.047); -1.19% (n=41) vs. +0.47% (n=66), lumbar spine (p=.017).

CONCLUSIONS

These results show BMD declines during DMPA-IM use; following discontinuation, significant increases in BMD occur through 96 weeks posttreatment.

Weight, fat mass, and central distribution of fat increase when women use depot-medroxyprogesterone acetate for contraception

OBJECTIVE

To compare longitudinal changes in weight, body fat, and ratio of central to peripheral fat mass among first-time depot-medroxyprogesterone acetate (DMPA) users to women using no hormonal contraception, and to evaluate user characteristics associated with that change.

DESIGN

Prospective longitudinal study.

SUBJECTS

Healthy women, aged 18-35 y, using DMPA for contraception (n=178) and women using no hormonal contraception (n=145).

MEASUREMENTS

Weight, body fat, and the central distribution of fat, measured at 3-month intervals for 30 months, by electronic scale and dual-energy X-ray absorptiometry (DEXA). The ratio of central to peripheral distribution of body fat was computed by dividing the body fat in the conventional DEXA trunk region of interest (ROI) by the ROI's that encompass the arms, hips and legs.

RESULTS

Women using DMPA had a significantly greater increase in all measures of fatness than women using no hormonal method of contraception (P<0.03). The observed weight of DMPA users increased from a mean of 69.4 kg (s.d.=16.9) at baseline to 75.5 kg (s.d.=25.0) at 30 months; an increase of 6.1 kg (8.8.%). Fat mass increased from a mean of 25.3 kg (s.d.=12.6 kg) at baseline to 31.4 kg (s.d.=17.8); an increase of 6.1 kg (23.6%) in DMPA users. The ratio of central to peripheral fat mass in DMPA users changed from 0.95 (s.d.=0.155) at baseline to 1.01(s.d.=0.198) at 30 months. In contrast, weight, fat mass and the ratio of central to peripheral fat mass of control participants remained virtually unchanged over the same time period. Women with higher baseline physical activity levels had a smaller increase in body fat (P=0.003) and the fat ratio (P=0.03), but not weight (P=0.48). No other user characteristics including, smoking, past oral contraceptive use or previous pregnancies predicted change in level of fatness.

CONCLUSIONS

This study has demonstrated a change in body composition toward greater fatness and toward a central redistribution of fat among DMPA users as compared to controls and provides important information to be used when counseling women regarding contraceptive methods. Given the potential long-term implication of these changes, further study is recommended to determine whether the gains in fatness are reversed following DMPA discontinuation and to examine the role of progestins in the development and maintenance of obesity.

Cyclic progestin administration increases energy expenditure and decreases body fat mass in perimenopausal women

OBJECTIVE

The menopause transition is characterized by luteal phase defect anovulatory cycles, and changes in body weight and body composition. Resting metabolic rate (RMR) is increased in the luteal phase of the menstrual cycle. We evaluated whether progestin administration increases RMR and influences body composition of perimenopausal women.

DESIGN

Thirty-six perimenopausal women were randomly allocated to receive either calcium (1 g/day) continuously plus the progestin nomegestrol acetate (NOMAc; 5 mg/day for 10 days x month for 12 months) or calcium alone. Body composition, RMR, energy intake, and climacteric and psychological symptoms were evaluated at baseline and after 12 months. In the NOMAc group, body composition and RMR analyses were performed twice during the first month of treatment. One evaluation was performed after almost 8 days of NOMAc adjunct, and an another before or almost 15 days after NOMAc administration.

RESULTS

Resting metabolic rate was increased by NOMAc administration of 54.5 +/- 73.8 kcal/24 h (P < 0.01). In women treated with NOMAc, fat mass decreased by 1.2 +/- 0.6 kg (P < 0.001). In comparison with controls, body weight (P < 0.05) and body mass index (P < 0.05) were also reduced after 12 months of therapy with NOMAc.

CONCLUSIONS

In perimenopausal women the use of NOMAc increases RMR. During the menopause transition, cyclic NOMAc administration may contribute to reduce negative modification of body composition.

Effects of gender and menstrual cycle phase on food-maintained responding under a progressive-ratio schedule in cynomolgus monkeys

Clinical and preclinical data suggest that fluctuations in ovarian steroid hormones across the menstrual/estrous cycle influence spontaneous feeding behavior in females. The effects of gender, menstrual cycle phase, and ovarian hormone fluctuations on food-maintained responding under a progressive-ratio schedule were investigated in four female and three male cynomolgus monkeys. Females were studied across 21 menstrual cycles, and ovulatory cycles were defined by analysis of ovarian steroid hormone levels. Data were analyzed for the early and mid-follicular phase and the mid- and late luteal phase of the menstrual cycle. Progressive-ratio break points for food were significantly higher in males than in females (p < 0.01). However, progressive-ratio break points did not vary consistently as a function of menstrual cycle phase during ovulatory cycles. There were no systematic patterns of progressive-ratio break points in anovulatory menstrual cycles. Only one female monkey reached significantly higher break points during the mid- and late luteal phases in comparison to the mid-follicular phase of the menstrual cycle (p < 0.05). There was also a significant positive correlation between progressive-ratio break points and progesterone levels and a significant negative correlation with estradiol in that monkey. Although fluctuations in ovarian steroid hormones may influence food consumption under some conditions, consistent patterns of food-maintained responding were not detected during ovulatory menstrual cycles in cynomolgus monkeys.

Subcutaneous depot medroxyprogesterone acetate versus leuprolide acetate in the treatment of endometriosis-associated pain

BACKGROUND

A clinical study compared efficacy and safety of depot medroxyprogesterone acetate (DMPA) with leuprolide for endometriosis-associated pain.

METHODS

This multicentre, 18 month, evaluator-blinded, comparator-controlled trial randomized 300 women with laparoscopically diagnosed endometriosis to 6 month treatment with subcutaneous injection of 104 mg/0.65 ml DMPA (DMPA-SC 104) every 3 months or leuprolide (3.75 mg monthly or 11.25 mg every 3 months), with 12 months post-treatment follow-up. Endpoints included patient response to treatment in five signs/symptoms (dysmenorrhoea, dyspareunia, pelvic pain, pelvic tenderness, induration) and changes in bone mineral density (BMD) and productivity at 6 and 18 months.

RESULTS

DMPA-SC 104 and leuprolide produced equivalent (P < 0.02) reductions in at least four pain categories and significant (P < 0.001) improvements in composite score at months 6 and 18. At month 6, reductions in total hip and lumbar spine BMD were significantly less (P < 0.001) with DMPA-SC 104 versus leuprolide. BMD returned to pre-treatment levels 12 months post-treatment in the DMPA-SC 104 but not the leuprolide group. Total productivity also significantly (P < or = 0.05) improved in both groups at 6 and 18 months.

CONCLUSIONS

DMPA-SC 104 reduces endometriosis-associated pain as effectively as leuprolide and improves productivity with significantly less BMD decline.

Endocrine control of body composition in infancy, childhood, and puberty

Body composition exhibits marked variations across the early human lifetime. The precise physiological mechanisms that drive such developmental adaptations are difficult to establish. This clinical challenge reflects an array of potentially confounding factors, such as marked intersubject differences in tissue compartments; the incremental nature of longitudinal intrasubject variations in body composition; technical limitations in quantitating the unobserved mass of mineral, fat, water, and muscle ad seriatim; and the multifold contributions of genetic, dietary, environmental, hormonal, nutritional, and behavioral signals to physical and sexual maturation. From an endocrine perspective (reviewed here), gonadal sex steroids and GH/IGF-I constitute prime determinants of evolving body composition. The present critical review examines hormonal regulation of body composition in infancy, childhood, and puberty.

Stress fracture injury in young military men and women

Approximately 5% of all military recruits incur stress fracture injuries during intense physical training, predominately in the lower extremity. We compared young men and women with stress fracture injury (subjects) to a matched group of uninjured volunteers (controls) during a summer training program at the United States Naval Academy to identify possible risk factors for stress fracture injury. The subject group was composed of 13 female and 18 male plebes with training-induced stress fracture injury verified by plain radiographs and/or nuclear bone scan. The control group was composed of 13 female and 18 male plebes who remained without injury during plebe summer training but who were matched with the 31 injured plebes for the Initial Strength Test (1-mi run time, means: women, 7.9 min; men, 6.4 min) and body mass index (means: women, 23.4; men, 23.8). We found that the subjects lost significant body weight (mean, 2.63 +/- 0.54 kg) between Day 1 and the date of their diagnosis of a stress fracture (mean, Day 35) and that they continued to lose weight until the date of their DEXA scan (mean, Day 49). Among female plebes, there was no evidence of the female athlete triad (eating disorders, menstrual dysfunction, or low bone density). Thigh girth was significantly smaller in female subjects than in female controls and trended to be lower in male subjects than in male controls. Total body bone mineral content was significantly lower in the male subjects than in male controls. Bone mineral density of the distal tibia and femoral neck were not significantly different between the groups. DEXA-derived structural geometric properties were not different between subjects and controls. Because, on average, tibias were significantly longer in male subjects than in male controls, the mean bone strength index in male subjects was significantly lower than that of male controls. We conclude that significant, acute weight loss combined with regular daily physical training among young military recruits may be a significant contributing risk factor for stress fracture injuries in young military men and women.

Phase of menstrual cycle affects lysine requirement in healthy women

The aim of this study was to investigate whether the phases of the menstrual cycle affect lysine requirement in healthy adult females, as determined by the indicator amino acid oxidation (IAAO) method. Five healthy females with regular menstrual cycles were studied at seven graded levels of lysine intake, in random order, with an oral [13C]phenylalanine tracer protocol in both the follicular and luteal phases. A total of 14 studies were conducted for each subject. Breath and plasma samples were collected according to the standard IAAO protocol. Serum 17beta-estradiol and progesterone concentrations were measured on each IAAO study day. The rate of release of 13CO2 from [13C]phenylalanine oxidation (F13CO2) was measured, and a two-phase linear regression crossover model was applied to determine lysine requirement. F13CO2 was higher during the luteal phase (P < 0.001) and was positively associated with serum concentrations of 17beta-estradiol and progesterone. The F13CO2 data were adjusted for subjects and sex hormones and used to define breakpoints for lysine requirements. The lysine requirement of healthy females in the luteal phase was 37.7 mg.kg(-1).day(-1) and higher (P = 0.025) than that of females in the follicular phase (35.0 mg.kg(-1).day(-1)). At all lysine intake levels, plasma amino acids were lower and phenylalanine oxidation was higher in the luteal relative to the follicular phase. Therefore, we reason that the higher lysine requirement observed in the luteal phase is probably due to higher amino acid catabolism.

Nondaily Hormonal Contraception: Considerations in Contraceptive Choice and Patient Counseling

PURPOSE

To review currently available choices for non-daily hormonal contraception, considering efficacy, safety, patient counseling issues, and appropriate patient selection.

DATA SOURCES

Worldwide medical literature and the individual products' prescribing information.

CONCLUSIONS

Patients and clinicians have many nondaily hormonal contraceptive options available--from Depo-Provera quarterly injection, which has been available in the United States for over 10 years, to several new entries (Mirena 5-year intrauterine system, Lunelle monthly injection, NuvaRing monthly intravaginal ring, and Ortho Evra weekly transdermal patch). All these options offer high efficacy and enhanced convenience for many patients over daily oral contraceptives (OCs). Barriers to use of these agents may include patients' lack of information as well as fear or misconceptions regarding the hormones and methods. All of these can be addressed with adequate patient counseling and open dialogue. The clinician and patient need to be well-informed regarding these options so that they can work together and identify the best contraceptive fit for the patient---with the ultimate goal being to increase patient satisfaction and adherence and, thus, avoid unintended pregnancy.

IMPLICATIONS FOR PRACTICE

Despite the efficacy of OCs, missed pills are quite common and contribute to unintended pregnancy. Many women in all population categories would benefit from the convenience and reliability of nondaily hormonal contraceptives. The highest efficacy rates with typical use are associated with agents that require minimal user participation (i.e., Depo-Provera, Mirena). Compared to daily regimens, all nondaily options offer increased convenience and may contribute to improved patient adherence. However, barriers to use may exist. Patient fears regarding use of hormones can be minimized by discussing the long-term safety of hormonal contraceptives. (The data are predominantly derived from Depo-Provera and OCs because these agents have been available in the United States and in the rest of the world for much longer than the newer nondaily options.) Patient counseling and appropriate expectations regarding changes in menstrual pattern have been demonstrated to further enhance patient adherence to therapy. Finally, patient lifestyle preferences must be considered. The finding that many women are comfortable with or even prefer amenorrhea, which is associated with options such as Depo-Provera, highlights how important it is for clinicians to avoid making assumptions about a patient's contraceptive preferences. Rather, clinicians and patients should exchange information through an open dialogue. For the majority of patients, nondaily hormonal contraceptives should be considered and offered as first-line options.