Urinary ovarian and gonadotropin hormone levels in premenopausal women with low bone mass

Intra- and inter-cycle variability of anti-Müllerian hormone (AMH) levels in healthy women during non-consecutive menstrual cycles: the BICYCLE study

OBJECTIVES

Determine variability of serum anti-Müllerian hormone (AMH) levels during ovulatory menstrual cycles between different women (inter-participant), between non-consecutive cycles (inter-cycle) and within a single cycle (intra-cycle) in healthy women.

METHODS

Eligible participants were women aged 18-40 years with regular ovulatory menstrual cycles. Serum samples were collected every second day during two non-consecutive menstrual cycles. AMH levels were measured in triplicate using the Elecsys^® AMH Plus immunoassay (Roche Diagnostics). AMH level variability was evaluated using mixed-effects periodic regression models based on Fourier series. The mesor was calculated to evaluate inter-participant and inter-cycle variability. Inter- and intra-cycle variability was evaluated using peak-to-peak amplitudes. Separation of biological and analytical coefficients of variation (CVs) was determined by analysing two remeasured AMH levels (with and without original AMH levels).

RESULTS

A total of 47 women were included in the analysis (42 assessed over two cycles; five one cycle only). CV of unexplained biological variability was 9.61%; analytical variability was 3.46%. Inter-participant variability, given by time-series plots of AMH levels, was greater than inter-cycle variability. Between individual participants, both mesor and peak-to-peak amplitudes proved variable. In addition, for each participant, intra-cycle variability was higher than inter-cycle variability.

CONCLUSIONS

Inter-participant and intra-cycle variability of AMH levels were greater than inter-cycle variability. Unexplained biological variability was higher than analytical variability using the Elecsys AMH Plus immunoassay. Understanding variability in AMH levels may aid in understanding differences in availability of antral ovarian follicles during the menstrual cycle, which may be beneficial in designing gonadotropin dosage for assisted reproductive technology.

Field methods and strategies for assessing female reproductive functioning

A detailed understanding of female reproductive functioning is important to many disciplines including anthropology, evolutionary theory, demography, psychology, and biomedicine. In this article, I describe strategies and methods that have been used successfully in community-based studies of human reproduction, many in remote locales, to produce high quality biomarker data. These techniques are applicable to a wide range of research questions and populations, and to persons from adolescence through senescence. I give particular attention to the inherent challenges imposed by the cyclical and somewhat unpredictable nature of the hypothalamic-pituitary-ovarian axis including the necessity and difficulty of ascertaining the timing and occurrence of ovulation, the limits of different sampling regimes for capturing fluctuations in reproductive hormones, and the critical importance of recognizing and, when possible, reducing selection bias. I discuss the relative advantages and disadvantages of collecting saliva, urine, and dried blood spots, and describe some of the subtleties involved in collecting contamination-free samples. Once samples are collected, they must be stored in a manner that minimizes degradation; I describe techniques to keep samples cold even without access to electricity or dry ice. I also discuss various issues that should be considered during initial discussions with a laboratory and when samples are assayed by the laboratory. I include examples of techniques that have worked well in actual field studies, and examples of flawed analytical approaches that should be avoided. With these and other tools, even under technology-sparse conditions, researchers can investigate variability in human physiology across the breadth of human habitats.

Efficient Semiparametric Regression for Longitudinal Data with Regularized Estimation of Error Covariance Function

Improving estimation efficiency for regression coefficients is an important issue in the analysis of longitudinal data, which involves estimating the covariance matrix of errors. But challenges arise in estimating the covariance matrix of longitudinal data collected at irregular or unbalanced time points. In this paper, we develop a regularization method for estimating the covariance function and a stepwise procedure for estimating the parametric components efficiently in the varying-coefficient partially linear model. This procedure is also applicable to the varying-coefficient temporal mixed effects model. Our method utilizes the structure of the covariance function and thus has faster rates of convergence in estimating the covariance functions and outperforms the existing approaches in simulation studies. This procedure is easy to implement and its numerical performance is investigated using both simulated and real data.

Progesterone for the prevention and treatment of osteoporosis in women

Estradiol (E2) is women's dominant 'bone hormone' since it is essential for development of adolescent peak bone mineral density (BMD) and physiological levels prevent the rapid (3-week) bone resorption that causes most adult BMD loss. However, deceasing E2 levels trigger bone resorption/loss. Progesterone (P4) is E2's physiological partner, collaborating with E2 in every cell/tissue; its bone 'job' is to increase P4-receptor-mediated, slow (3-4 months) osteoblastic new bone formation. When menstrual cycles are normal length and normally ovulatory, E2 and P4 are balanced and BMD is stable. However, clinically normal cycles commonly have ovulatory disturbances (anovulation, short luteal phases) and low P4 levels; these are more frequent in teen and perimenopausal women and increased by everyday stressors: energy insufficiency, emotional/social/economic threats and illness. Meta-analysis shows that almost 1%/year spinal BMD loss occurs in those with greater than median (∼31%) of ovulatory disturbed cycles. Prevention of osteoporosis and fragility fractures requires the reversal of stressors, detection and treatment of teen-to-perimenopausal recurrent cycle/ovulatory disturbances with cyclic oral micronized progesterone. Low 'Peak Perimenopausal BMD' is likely the primary risk for fragility fractures in later life. Progesterone plus estradiol or other antiresorptive therapies adds 0.68%/year and may be a highly effective osteoporosis treatment. Randomized controlled trials are still needed to confirm progesterone's important role in women's bone formation.

Towards the Clinical Evaluation of the Luteal Phase in Fertile Women: A Preliminary Study of Normative Urinary Hormone Profiles

Objective: To describe and evaluate urinary hormone profiles in the luteal phase.

Setting and Patients: Twenty-five healthy fertile women, with regular ovulatory pattern cycles as assessed by temperature and cervical mucus, at a university based center.

Methods: Daily urinary hormonal assessment of luteinizing hormone, estrone glucuronide, and pregnanediol glucuronide. This was done during 3 or more cycles, with 78 completed cycles. Samples were analyzed by both crude levels and levels adjusted for the hormone excretion rate. Correlation between measured parameters (LH surge, vulvar mucus) was assessed with regard to their ability to detect presumed ovulation.

Results: An upper, middle, and lower tercile range for the main urinary reproductive hormones was determined and a classification system of zones proposed, considering profiles over or under the 10th percentile. Adjustment for the urine excretion rate proved useful for interpreting individual samples; this was less necessary with multiple samples over time where trends could be determined. This serial evaluation, in at least two cycles, lowered the possibility of finding an isolated luteal phase defect and helped identify the recurrence of such. Vulvar mucus findings performed well in determining the timing of ovulation. Despite the proven fertility of the study population, lower luteal phase hormones were detected in both an isolated and, in some situations, recurrent manner.

Conclusion: A feasible method is proposed to accurately, thoroughly and reproducibly study the luteal phase in order to evaluate and treat identified abnormalities in a properly timed, restorative manner. This preliminary study provides the basis for future research, correlating urinary hormones with clinical findings, particularly those of luteal phase defects.

Estimation of the linear mixed integrated Ornstein-Uhlenbeck model

The linear mixed model with an added integrated Ornstein–Uhlenbeck (IOU) process (linear mixed IOU model) allows for serial correlation and estimation of the degree of derivative tracking. It is rarely used, partly due to the lack of available software. We implemented the linear mixed IOU model in Stata and using simulations we assessed the feasibility of fitting the model by restricted maximum likelihood when applied to balanced and unbalanced data. We compared different (1) optimization algorithms, (2) parameterizations of the IOU process, (3) data structures and (4) random-effects structures. Fitting the model was practical and feasible when applied to large and moderately sized balanced datasets (20,000 and 500 observations), and large unbalanced datasets with (non-informative) dropout and intermittent missingness. Analysis of a real dataset showed that the linear mixed IOU model was a better fit to the data than the standard linear mixed model (i.e. independent within-subject errors with constant variance).

Variable selection in rank regression for analyzing longitudinal data

In this paper, we consider variable selection in rank regression models for longitudinal data. To obtain both robustness and effective selection of important covariates, we propose incorporating shrinkage by adaptive lasso or SCAD in the Wilcoxon dispersion function and establishing the oracle properties of the new method. The new method can be conveniently implemented with the statistical software R. The performance of the proposed method is demonstrated via simulation studies. Finally, two datasets are analyzed for illustration. Some interesting findings are reported and discussed.

Ovulation Prevalence in Women with Spontaneous Normal-Length Menstrual Cycles - A Population-Based Cohort from HUNT3, Norway

BACKGROUND

Ovulatory menstrual cycles are essential for women's fertility and needed to prevent bone loss. There is a medical/cultural expectation that clinically normal menstrual cycles are inevitably ovulatory. Currently within the general population it is unknown the proportion of regular, normal-length menstrual cycles that are ovulatory. Thus, the objective of this study was to determine the population point prevalence of ovulation in premenopausal, normally menstruating women. The null hypothesis was that such cycles are ovulatory.

METHODS

This is a single-cycle, cross-sectional, population-based study-a sub-study of the HUNT3 health study in the semi-rural county (Nord Trøndelag) in mid-Norway. Participants included >3,700 spontaneously (no hormonal contraception) menstruating women, primarily Caucasian, ages 20-49.9 from that county. Participation rate was 51.9%. All reported the date previous flow started. A single, random serum progesterone level was considered ovulatory if ≥9.54 nmol/L on cycle days 14 to -3 days before usual cycle length (CL).

RESULTS

Ovulation was assessed in 3,168 women mean age 41.7 (interquartile range, [IQR] 36.8 to 45.5), cycle length 28 days (d) (IQR 28 to 28) and body mass index (BMI) 26.3 kg/m2 (95% CI 26.1 to 26.4). Parity was 95.6%, 30% smoked, 61.3% exercised regularly and 18% were obese. 1,545 women with a serum progesterone level on cycle days 14 to -3 were presumed to be in the luteal phase. Of these, 63.3% of women had an ovulatory cycle (n = 978) and 37% (n = 567) were anovulatory. Women with/ without ovulation did not differ in age, BMI, cycle day, menarche age, cigarette use, physical activity, % obesity or self-reported health. There were minimal differences in parity (96.7% vs. 94.5%, P = 0.04) and major differences in progesterone level (24.5 vs. 3.8 nmol/L, P = 0.001).

CONCLUSION

Anovulation in a random population occurs in over a third of clinically normal menstrual cycles.

Actigraphy-defined measures of sleep and movement across the menstrual cycle in midlife menstruating women: Study of Women's Health Across the Nation Sleep Study

OBJECTIVE

This study aims to evaluate patterns in actigraphy-defined sleep measures across the menstrual cycle by testing the hypothesis that sleep would be more disrupted in the premenstrual period (ie, within the 14 d before menses).

METHODS

A community-based longitudinal study of wrist actigraphy-derived sleep measures was conducted in 163 (58 African American, 78 white, and 27 Chinese) late-reproductive-age (mean [SD], 51.5 [2.0] y) women from the Study of Women's Health Across the Nation Sleep Study. Daily measures of sleep (sleep efficiency [%] and total sleep time [minutes]) and movement during sleep (mean activity score [counts]) were characterized using wrist actigraphy across a menstrual cycle or 35 days, whichever was shorter. Data were standardized to 28 days to account for unequal cycle lengths and divided into four weekly segments for analyses.

RESULTS

Sleep efficiency declined gradually across the menstrual cycle, but the decline became pronounced on the fourth week (the premenstrual period). Compared with the third week, sleep efficiency declined by 5% (P < 0.0001) and mean total sleep time was 25 minutes less (P = 0.0002) on the fourth week. We found no significant differences between the mean for the second week and the mean for the third week. The association of weekly segments with sleep efficiency or total sleep time was modified by sociodemographic and lifestyle factors, including body mass index, race, study site, financial strain, marital status, and smoking.

CONCLUSIONS

Among late-reproductive-age women, sleep varies systematically across the menstrual cycle, including a gradual decline in sleep efficiency across all weeks, with a more marked change premenstrually during the last week of the menstrual cycle. These sleep changes may be modified by altering lifestyle factors.

2014 Female Athlete Triad Coalition consensus statement on treatment and return to play of the female athlete triad: 1st International Conference held in San Francisco, CA, May 2012, and 2nd International Conference held in Indianapolis, IN, May 2013

The Female Athlete Triad is a medical condition often observed in physically active girls and women, and involves 3 components: (1) low energy availability with or without disordered eating, (2) menstrual dysfunction, and (3) low bone mineral density. Female athletes often present with 1 or more of the 3 Triad components, and an early intervention is essential to prevent its progression to serious endpoints that include clinical eating disorders, amenorrhea, and osteoporosis. This consensus statement represents a set of recommendations developed following the first (San Francisco, California) and second (Indianapolis, Indianna) International Symposia on the Female Athlete Triad. It is intended to provide clinical guidelines for physicians, athletic trainers, and other health care providers for the screening, diagnosis, and treatment of the Female Athlete Triad and to provide clear recommendations for return to play. The 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad Expert Panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision-making regarding sport participation, clearance, and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team, and implementation of treatment contracts. This consensus paper has been endorsed by The Female Athlete Triad Coalition, an International Consortium of leading Triad researchers, physicians, and other health care professionals, the American College of Sports Medicine, and the American Medical Society for Sports Medicine.

Bone mineral density assessment in premenopausal women

In the absence of fragility fractures, low bone mineral density may reflect attainment of a lower peak bone mass in comparison with the young adult mean value. It is necessary to distinguish between low peak bone mass and a systemic disorder resulting in low bone mineral density and skeletal fragility. Low peak bone mass in the absence of fragility fracture or progressive bone loss may not require pharmacological intervention. However, systemic disorders contributing to bone loss do require diagnosis and intervention. Common causes of low bone density in premenopausal women include ovulatory disturbances and low body weight. Other diseases, conditions or medications may also contribute to bone loss and these should be identified and treated if present. Fracture risk is reduced by lifestyle changes and pharmacological intervention in those with glucocorticoid-induced bone loss. Discontinuing depo medroxyprogesterone acetate use has been associated with improvements in bone mineral density. Bone mineral density alone is insufficient for the diagnosis of osteoporosis in premenopausal women in the absence of fragility fractures. Bone mineral density testing should only be performed in premenopausal women in the presence of approved indications.

Progesterone and bone: actions promoting bone health in women

Estradiol (E(2)) and progesterone (P(4)) collaborate within bone remodelling on resorption (E(2)) and formation (P(4)). We integrate evidence that P(4) may prevent and, with antiresorptives, treat women's osteoporosis. P(4) stimulates osteoblast differentiation in vitro. Menarche (E(2)) and onset of ovulation (P(4)) both contribute to peak BMD. Meta-analysis of 5 studies confirms that regularly cycling premenopausal women lose bone mineral density (BMD) related to subclinical ovulatory disturbances (SODs). Cyclic progestin prevents bone loss in healthy premenopausal women with amenorrhea or SOD. BMD loss is more rapid in perimenopause than postmenopause-decreased bone formation due to P(4) deficiency contributes. In 4 placebo-controlled RCTs, BMD loss is not prevented by P(4) in postmenopausal women with increased bone turnover. However, 5 studies of E(2)-MPA co-therapy show greater BMD increases versus E(2) alone. P(4) fracture data are lacking. P(4) prevents bone loss in pre- and possibly perimenopausal women; progesterone co-therapy with antiresorptives may increase bone formation and BMD.

A prospective exploration of cognitive dietary restraint, subclinical ovulatory disturbances, cortisol, and change in bone density over two years in healthy young women

CONTEXT

Cross-sectional studies have found associations among elevated cognitive dietary restraint (CDR), increased ovulatory disturbances, and lower bone mass, possibly mediated by cortisol.

OBJECTIVE

To determine whether healthy young women with higher CDR have more menstrual cycles with subclinical ovulatory disturbances (SOD), elevated 24-h urinary free cortisol (UFC), and less positive 2-yr areal bone mineral density change (Delta-aBMD).

DESIGN, SETTING, AND PARTICIPANTS

We conducted a 2-yr longitudinal study of 123 healthy, community-dwelling, nonobese, regularly menstruating women aged 19-35 yr.

MAIN OUTCOME MEASURES

Key variables were Three Factor Eating Questionnaire Restraint score, percent of cycles with anvoluation and/or luteal phase length <10 d (%SOD), UFC, and Delta-aBMD at the lumbar spine (L1-L4), total hip, and whole body. Anthropometrics, general stress, physical activity, and energy intake were measured. Adjusting for potential confounders, differences were examined by general linear modeling using median split of CDR score and %SOD.

RESULTS

Women with higher CDR had higher %SOD (56 vs. 34%, P < 0.001) and higher UFC (28.0 vs. 24.0 microg/d, P = 0.021). Delta-aBMD did not differ by CDR. Women with higher %SOD had less positive Delta-aBMD at L1-L4 (0.7 vs. 1.9%, P = 0.034) and hip (-0.6 vs. 0.9%, P = 0.001), and higher CDR score (8.7 vs. 7.1, P = 0.04). Physical activity, general stress, body mass index, and energy intake did not explain differences by CDR or %SOD. UFC was not associated with %SOD or Delta-aBMD.

CONCLUSION

Women with more frequent SOD reported higher CDR and experienced less positive Delta-aBMD. Although women with higher CDR had higher UFC, the mechanism linking CDR, SOD, and aBMD is not clear.

Bayesian inference in semiparametric mixed models for longitudinal data

We consider Bayesian inference in semiparametric mixed models (SPMMs) for longitudinal data. SPMMs are a class of models that use a nonparametric function to model a time effect, a parametric function to model other covariate effects, and parametric or nonparametric random effects to account for the within-subject correlation. We model the nonparametric function using a Bayesian formulation of a cubic smoothing spline, and the random effect distribution using a normal distribution and alternatively a nonparametric Dirichlet process (DP) prior. When the random effect distribution is assumed to be normal, we propose a uniform shrinkage prior (USP) for the variance components and the smoothing parameter. When the random effect distribution is modeled nonparametrically, we use a DP prior with a normal base measure and propose a USP for the hyperparameters of the DP base measure. We argue that the commonly assumed DP prior implies a nonzero mean of the random effect distribution, even when a base measure with mean zero is specified. This implies weak identifiability for the fixed effects, and can therefore lead to biased estimators and poor inference for the regression coefficients and the spline estimator of the nonparametric function. We propose an adjustment using a postprocessing technique. We show that under mild conditions the posterior is proper under the proposed USP, a flat prior for the fixed effect parameters, and an improper prior for the residual variance. We illustrate the proposed approach using a longitudinal hormone dataset, and carry out extensive simulation studies to compare its finite sample performance with existing methods.

Detecting evidence of luteal activity by least-squares quantitative basal temperature analysis against urinary progesterone metabolites and the effect of wake-time variability

OBJECTIVE

To assess computerised least-squares analysis of quantitative basal temperature (LS-BT) against urinary pregnanediol glucuronide (PdG) as an indirect measure of ovulation, and to evaluate the stability of LS-QBT to wake-time variation.

STUDY DESIGN

Cross-sectional study of 40 healthy, normal-weight, regularly menstruating women aged 19-34. Participants recorded basal temperature and collected first void urine daily for one complete menstrual cycle. Evidence of luteal activity (ELA), an indirect ovulation indicator, was assessed using Kassam's PdG algorithm, which identifies a sustained 3-day PdG rise, and the LS-QBT algorithm, by determining whether the temperature curve is significantly biphasic. Cycles were classified as ELA(+) or ELA(-). We explored the need to pre-screen for wake-time variations by repeating the analysis using: (A) all recorded temperatures, (B) wake-time adjusted temperatures, (C) temperatures within 2h of average wake-time, and (D) expert reviewed temperatures.

RESULTS

Relative to PdG, classification of cycles as ELA(+) was 35 of 36 for LS-QBT methods A and B, 33 of 34 (method C) and 30 of 31 (method D). Classification of cycles as ELA(-) was 1 of 4 (methods A and B) and 0 of 3 (methods C and D). Positive predictive value was 92% for methods A-C and 91% for method D. Negative predictive value was 50% for methods A and B and 0% for methods C and D. Overall accuracy was 90% for methods A and B, 89% for method C and 88% for method D. The day of a significant temperature increase by LS-QBT and the first day of a sustained PdG rise were correlated (r=0.803, 0.741, 0.651, 0.747 for methods A-D, respectively, all p<0.001).

CONCLUSION

LS-QBT showed excellent detection of ELA(+) cycles (sensitivity, positive predictive value) but poor detection of ELA(-) cycles (specificity, negative predictive value) relative to urinary PdG. Correlations between the methods and overall accuracy were good and similar for all analyses. Findings suggest that LS-QBT is robust to wake-time variability and that expert interpretation is unnecessary. This method shows promise for use as an epidemiological tool to document cyclic progesterone increase. Further validation relative to daily transvaginal ultrasound is required.

Implications of diminished ovarian reserve (DOR) extend well beyond reproductive concerns

OBJECTIVES

To investigate whether a diagnosis of diminished ovarian reserve (DOR) in premenopausal years has adverse implications for skeletal health and quality of life.

DESIGN

This was a cross-sectional study of infertile, albeit healthy, mid-reproductive-age women (younger than 42 y) attending an academic infertility practice.

RESULTS

Eighty-nine women with varying causes of infertility were prospectively enrolled. Serum (cycle d 1-3) was collected for markers of ovarian reserve, bone metabolism, testosterone, and free androgen index. Bone mineral density (BMD) was assessed and categorized as low if the Z score was less than -1.0). Infertile women with DOR (n = 28) demonstrated significantly higher serum follicle-stimulating hormone levels (P < 0.001), lower müllerian-inhibiting substance (MIS) levels (P < 0.001), smaller ovarian dimensions (P < 0.05), lower testosterone levels (P = 0.035), lower free androgen index (P = 0.019), and enhanced bone metabolism (P = 0.003); although the prevalence of low BMD was higher in women with DOR who were younger than 41, this relationship was not of statistical significance (P = 0.106). Women younger than 41 years of age with DOR were significantly more likely to manifest disturbed sleep (P = 0.049) and acknowledge dissatisfaction with sexual intimacy (P = 0.004) compared with those with infertility and normal ovarian reserve. After adjustment for potential confounders, a diagnosis of DOR was significantly associated with low BMD, increased bone turnover, sexual dissatisfaction, and disturbed sleep.

CONCLUSIONS

Our data suggest that DOR unmasked in the context of infertility evaluation has adverse implications for a woman's well-being that extend well beyond the thus far appreciated reproductive concerns. A decline in ovarian hormones, specifically estrogen and testosterone, concomitant with DOR may be hypothesized as a mechanism that can explain the observed multisystem ramifications of DOR including increased bone turnover, low BMD, sexual distress, and disturbed sleep.

Assessment of urinary total testosterone production by a highly sensitive time-resolved fluorescence immunoassay

Radioimmunoassay (RIA) that involves purification of the analyte by organic solvent extraction is widely used. Although the extraction RIA is reliable when properly validated, it is time consuming and radioactive, we measure urinary total testosterone with a highly sensitive rapid and accurate time-resolved fluorescence immunoassay (TRFIA) method. High affinity antitestosterone antibody and Eu(3+) labeled Donkey antisheep IgG as tracers were used. The assay was evaluated for specificity, sensitivity, analytical recovery, precision and dilution linearity by the TRFIA method on urine samples. A satisfactory standard curve for testosterone TRFIA has been developed with good sensitivity (5.1 pmol/L). The validity of the assay for urinarytotal testosterone was confirmed by the good correlation between the results obtained by TRFIA (X) and those RIA (Y) (Y=0.075+0.971X, R=0.992). Specificity, analytical recovery, precision and dilution linearity studies were determined and all found to be satisfactory. Male urinary total testosterone excretion ranged from 64.00 to 374.11 nmol/24 hr, which was about four times more than the range for women urinary testosterone excretion (14.16-100.65 nmol/24 hr), which suggests that a direct, reliable, easy to automate, highly sensitive and specific TRFIA type assay for the measurement of total testosterone in urine samples has been developed.

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

BACKGROUND

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

STUDY DESIGN

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

RESULTS

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

CONCLUSIONS

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

Vasomotor symptoms in infertile premenopausal women: a hitherto unappreciated risk for low bone mineral density

OBJECTIVE

To identify the prevalence of vasomotor symptoms (VMS) in a population of premenopausal infertile women and to determine whether VMS is associated with enhanced bone turnover and low bone mineral density (BMD).

DESIGN

Cross-sectional study.

SETTING

Academic infertility practice.

PATIENT(S)

Eighty-two premenopausal infertile, but otherwise healthy, women attending for routine infertility care.

INTERVENTION(S)

Bone mineral density testing, general health and Profile of Mood States questionnaires, and serum samples (cycle d 1-3).

MAIN OUTCOME MEASURE(S)

Vasomotor symptoms, specifically hot flashes (HF) and night sweats (NS); BMD z score, BMD categorized as low (Z <or= -1.0) or normal (Z > -1.0); ovarian reserve assessment (biochemical and ovarian dimensions on transvaginal ultrasound); and serum markers of bone turnover (collagen N-terminal telo-peptide, tartrate-resistant acid phosphatase, and bone-specific alkaline phosphatase) and ovarian reserve (FSH, E(2), and inhibin B). Multivariable regression analyses determined the associations between VMS, BMD, and bone turnover (individual markers and composite turnover score).

RESULT(S)

The prevalence of VMS was 12% in this relatively young population (mean [+/- SD] age [years], 34.53 +/- 4.32). Symptomatic women were statistically significantly more likely to report sleep disturbances and to exhibit evidence of low BMD, as well as to exhibit enhanced bone turnover and poorer ovarian reserve parameters. Multivariable logistic regression analyses confirmed the statistical significance of both HF and NS as independent correlates to low BMD after adjusting for age, body mass index, smoking status, menstrual regularity, and ovarian reserve status. Multivariable linear regression analyses demonstrated that NS, but not HF, predicted higher bone turnover at a statistically significant level after adjusting for age, smoking, menstrual regularity, and ovarian reserve.

CONCLUSION(S)

We demonstrate, in a premenopausal population of infertile women, evidence of morbid accompaniments to VMS, including sleep disturbances and evidence of low BMD. Our data further suggest a state of enhanced bone turnover in association with VMS, specifically in those experiencing NS. Declining ovarian reserve may be the common pathophysiological mechanism underlying VMS and low BMD in the symptomatic population and merits further investigation.

A prospective investigation of the relations among cognitive dietary restraint, subclinical ovulatory disturbances, physical activity, and bone mass in healthy young women

BACKGROUND

Cognitive dietary restraint (CDR) may mediate subclinical ovulatory disturbances, which may result in loss of bone mineral density (BMD). CDR is associated with greater physical activity, which may modify the effect of CDR and ovulatory disturbances on bone mass.

OBJECTIVE

We aimed to investigate the relations among CDR, ovulatory disturbances, and physical activity and their effect on BMD in healthy premenopausal women over a 2-y period.

DESIGN

In this prospective cohort study, key explanatory factors, important covariates, and BMD were measured at baseline and at 12 and 24 mo; 225 women completed the baseline assessment, and 189 completed the study. CDR was measured with the Three-Factor Eating Questionnaire, and physical activity was measured with the Baecke scale. An average of 9.8 menstrual cycles in 2 y were monitored by using salivary progesterone measurements and urinary ovulation detection kits. Ovulatory disturbances included anovulatory cycles or short luteal phase lengths of <10 d. BMD at the lumbar spine, femoral neck, and total body was measured by using dual-energy X-ray absorptiometry. General linear mixed modeling was used to determine predictors of change in BMD over time.

RESULTS

CDR was not associated with ovulatory disturbances or changes in BMD. The average annual rate of change in lumbar spine BMD was decreased by 0.01 g/cm(2) in women who had experienced > or =3 monitored cycles with ovulatory disturbances (P = 0.02).

CONCLUSIONS

CDR did not predict bone loss, and there was no relation between CDR and ovulatory disturbances. Ovulatory disturbances had a negative effect on the rate of change at the lumbar spine. The cause of these disturbances is unknown.

Fragility fractures and bone mineral density in HIV positive women: a case-control population-based study

This Canadian study of bone health showed that HIV+ women were more likely to have had fragility fractures (OR 1.7) but had BMD values that were not different than women from a national population-based cohort.

INTRODUCTION

Given that 17.5 million women globally are HIV-infected and living longer on anti-retroviral therapy (ART+), it is essential to determine whether they are at risk for osteoporosis as is currently assumed.

METHODS

Assessment of osteoporosis risk factors and lifetime low-trauma (fragility) fracture history used a common interviewer-administered questionnaire and phantom-adjusted bone mineral density (BMD). This study compared HIV+ Canadian women with age- and region-matched control women (1:3) from a national population-based study of osteoporosis.

RESULTS

One hundred and thirty-eight HIV+ women (100 ART+, 38 ART-) were compared with 402 controls. There were no differences in age (37.7 vs. 38.0 years), BMI (25.0 vs. 26.2), family history of osteoporosis, exercise history, alcohol or calcium intakes, age at menarche, oral contraceptive use or parity. HIV+ cases included more Aboriginal and Black women (12.5% and 16.2 vs. 2% and 1%, respectively), smoked and used injection drugs (53%) more, were more often treated with glucocorticoids, had oligomenorrhea, and reported 10-kg weight cycling. Significantly more HIV+ women reported lifetime fragility fractures (26.1% vs. 17.3; OR 1.7, 95% CI 1.1, 2.6). HIV+ and control women did not differ in BMD: spine 1.0 +/- 0.12 vs.1.0 +/- 0.14 g/cm(2) (diff. 0.0, 95% CI -0.27, 0.27) or total femur 0.91 +/- 0.15 vs. 0.93 +/- 0.12 g/cm(2) (diff 0.02, 95% CI +0.005, -0.045).

CONCLUSION

HIV+ women reported significantly more past osteoporotic fractures than population-based controls despite normal BMD. Research is needed to assess bone microarchitecture and develop a reliable fracture risk assessment tool for HIV+ women.

Bone mass and soy isoflavones in socially housed, premenopausal macaques

BACKGROUND

Soy consumption is associated with a lower incidence of hip fracture in Asian than in Western women, an effect often attributed to estrogen-like compounds (isoflavones) in soy. It is not known whether premenopausal soy exposure initiated in adulthood can increase bone mass and thereby reduce fracture risk.

OBJECTIVE

We aimed to determine whether a high-isoflavone soy diet influences bone mass in soy-naïve, premenopausal cynomolgus monkeys (Macaca fascicularis).

DESIGN

Ninety-four skeletally mature females were randomly assigned to consume diets whose protein content came from either high-isoflavone soy or casein and lactalbumin. Animals were socially housed. Bone mass and circulating isoflavone concentrations were measured at baseline and 19 and 31 mo after the start of treatment; bone biomarkers were measured at baseline and 31 mo.

RESULTS

There were no significant differences at any timepoint in whole-body bone mineral content between casein-fed (112.5 +/- 2.1, 119.2 +/- 1.9, and 120.7 +/- 2.1 g) and soy-fed (117.2 +/- 2.1, 122.4 +/- 2.0, and 125.4 +/- 2.3 g; P=0.12) monkeys. Similar results were seen for spinal bone mineral density (casein-fed: 0.46 +/- 0.01, 0.50 +/- 0.01, and 0.52 +/- 0.01 g/cm(2); soy-fed: 0.47 +/- 0.01, 0.51 +/- 0.01, and 0.52 +/- 0.01 g/cm(2); P=0.30) and bone biomarker measurements-bone-specific alkaline phosphatase (soy-fed: 82.3 +/- 4.1 and 63.2 +/- 3.4 ng/mL; casein-fed: 94.1 +/- 4.5 and 61.7 +/- 4.3 ng/mL; P=0.22) and C-terminal crosslink of type 1 collagen (soy-fed: 0.944 +/- 0.06 and 0.89 +/- 0.08 nmol/L; casein-fed: 0.97 +/- 0.07 and 0.78 +/- 0.06 nmol/L; P=0.20).

CONCLUSION

A soy diet high in isoflavones does not significantly affect bone characteristics in initially soy-naïve premenopausal monkeys.

Menstrual cycle lengths and bone mineral density: a cross-sectional, population-based study in rural Chinese women ages 30-49 years

INTRODUCTION

The menstrual cycle involves periodic fluctuations in estrogen and progesterone levels. Longer cycles have been associated with longer follicular phase, delayed estrogen peak and a lower mean oestradiol level of the entire cycle.

METHODS

We hypothesized that prolonged menstrual cycle length is associated with decreased bone mineral density (BMD) in a population of pre- and perimenopausal women. This population-based cross-sectional study was conducted in rural Anhui province, China. It includes 4,771 women, aged 30 to 49 years, who did not smoke or drink alcohol, and did not use oral contraceptives or breastfeed during the previous year. Dual-energy X-ray absorptionometry (DEXA) BMD measurements were taken at four skeletal sites: whole body, total hip, femoral neck and lumbar spine. Menstrual cycle characteristics (polymenorrhea, short normal, long normal, oligomenorrhea, 90-day amenorrhea, irregular cycle) in the prior year were assessed by questionnaire.

RESULTS

Prolonged menstrual cycle was consistently associated with decreased BMD at whole body, total hip, and femoral neck in both age 30-39, and age 40-49 stratum (p(trend)<0.05). Prolonged menstrual cycle was also associated with decreased lumbar spine BMD for women aged 40-49 (p(trend)<0.05). Among women with normal cycles aged 30-39, menstrual cycle length in the previous year was inversely associated with whole-body BMD (p<0.05). Women with 90-day amenorrhea had significantly lower mean total hip and femoral neck BMD relative to women with short normal cycles in the 30-39 age group; and had significantly lower whole body and total hip BMD relative to short normal cycles in the 40-49 age group. BMD in polymenorrheic women did not differ from BMD in women with short normal cycles at any of the skeletal sites.

CONCLUSIONS

We conclude that prolonged menstrual cycle length is associated with decreased BMD in pre- and perimenopausal women in this population.

FSH and bone--important physiology or not?

For many years, osteoporosis in women was equated with estrogen deficiency. The recent articles by Zaidi and colleagues offer a new challenge to the estrogen-deficiency-osteoporosis hypothesis by showing that follicle-stimulating hormone (FSH) stimulates osteoclastic bone resorption perhaps through tumor necrosis factor-alpha (TNF-alpha). These authors, however, neglected to mention bone abnormalities and high testosterone levels that were previously shown in FSH-receptor knockout and other modified mice. It is also possible that they have overemphasized potential relationships of these new data with human bone loss. Despite these fascinating data, the paradigm of FSH causing hypogonadal bone loss is not yet ready to displace the estrogen-deficiency-osteoporosis paradigm, although that model already faces considerable challenge.

Principais causas de diminuição da massa óssea em mulheres na pré-menopausa encaminhadas ao ambulatório de doenças ósteo-metabólicas de um Hospital Terciário de Curitiba

Selecionamos mulheres pré-menopausadas com redução da DMO encaminhadas ao ambulatório de Metabolismo Ósseo do Hospital de Clínicas da UFPR, com o objetivo de definirmos o perfil destas pacientes em relação aos fatores de risco e prováveis causas secundárias de osteoporose. Trinta e quatro mulheres foram estudadas (1948 anos). Em 29 pacientes (85,3%) a coluna lombar estava acometida, 8 (23,5%) apresentaram Z-score < -2,5 e 21 (61,8%) Z-score entre -1,0 e -2,5. Vinte pacientes (58,8%) apresentaram redução da DMO em fêmur, 2 (6,2%) com Z-score < -2,5 e 18 (56,2%) com Z-score entre -1,0 e -2,5. Causa secundária foi identificada em 26 pacientes (76,5%). Este estudo demonstra que a realização de densitometria óssea é importante em mulheres na pré-menopausa com fatores de risco para redução da massa óssea, uma vez que permite o início precoce do tratamento e a prevenção das complicações relacionadas.

Osteoporosis in otherwise healthy perimenopausal and early postmenopausal women: physical and biochemical characteristics

Population studies have shown that about 3-5% of perimenopausal women already have osteoporosis according to the WHO definition of osteoporosis for postmenopausal women ( t -score<or=-2.5). In general, this bone loss arises from well-characterized diseases or conditions that affect acquisition of peak bone mass and/or the rate of bone loss after peak bone mass has been attained. However, there often remains a subset of these women, with no identifiable cause of bone loss. This group has so far been little studied. We prospectively evaluated a group of 60 perimenopausal and early postmenopausal women (mean age 52.2+/-2.5 years) who were found to have apparently unexplained low bone mass, and we compared them to 120 controls matched for age and menopausal status. These women were extensively investigated, including by detailed questionnaire and laboratory testing. Of the 60 women with osteoporosis, only three were found to have previously undiagnosed disorders (two with subclinical hyperthyroidism and one with elevated serum PTH levels) that might have contributed to their low bone mass. On the other hand, osteoporotic patients were characterized by a significantly lower body weight, higher prevalence of personal and parental histories of fractures and a higher level of bone turnover as assessed by increased serum osteocalcin and bone alkaline phosphatase levels and urinary type I collagen C-telopeptide (CTX) excretion, as compared to controls. These findings support theories of a genetic contribution to osteoporosis and underline the predictive value of a previous history of personal and familial fracture in the identification of osteoporosis in early postmenopausal women.

Development and validation of a simple and direct ELISA method for the determination of conjugated (glucuronide) and non-conjugated testosterone excretion in urine

BACKGROUND

Several methods are now available to estimate urinary testosterone levels that can only be performed in established big laboratories using GC/MS techniques. In clinical practice or for research projects, an inexpensive method that does not require skilled technicians would be useful. A simple, rapid and accurate ELISA method has been developed and applied in our laboratory to measure urinary non-conjugated and total testosterone.

METHODS

High affinity anti-testosterone antibody and HRP-Donkey anti-sheep IgG (Horse Radish Peroxidase) as enzyme tracer were used to develop the ELISA method. The assay was evaluated for specificity, sensitivity, parallelism, accuracy and imprecision by the established methods on samples obtained from healthy volunteers. The results from the direct ELISA were compared to those after enzyme hydrolysis plus solvent extraction and HPLC or commercial kits.

RESULTS

A satisfactory standard curve for the direct testosterone ELISA has been developed with good sensitivity. Cross-reactivity values of anti-testosterone antibody with major interfering steroids were minimal except for testosterone-3-glucuronide (58.8%). The validity of urinary testosterone assay was confirmed by the good correlation between the results obtained by the direct ELISA and those after enzyme hydrolysis and solvent extraction (Y = 0.987X + 0.398, R2 = 0.97). Accuracy studies, parallelism and imprecision data were determined and all found to be satisfactory. Urinary testosterone excretion values obtained by our direct ELISA from healthy volunteers were generally in agreement with those published by other workers. Male urinary total testosterone excretion (non-conjugated and testosterone glucuronide) ranged from 177.9 to 865.3 nmol/day, which was about 3-6 times more than the range for women urinary testosterone excretion (34.5-308.8 nmol/day).

CONCLUSION

A direct, reliable, easy to perform, sensitive and highly specific ELISA type assay for the measurement of total testosterone in urine samples (conjugated and non-conjugated) has been developed. The novel features of the assay are that it does not require an initial extraction step or involve time consuming procedures such as chromatography. A simple method has also been developed to measure non-conjugated urinary testosterone excretion after solvent extraction alone.

Idiopathic osteoporosis in premenopausal women

Although osteoporosis predominantly affects older postmenopausal women, low bone mineral density also occurs in men and younger women. In men, it is often unexplained by recognized secondary causes. These men with idiopathic osteoporosis have reductions in serum IGF-I as well as indices of reduced bone formation. Younger women also experience bone loss of unknown etiology (IOP). Whether premenopausal women with IOP have similar decreases in IGF-I levels and reduced indices of bone formation is unknown. We prospectively evaluated a group of premenopausal women with unexplained low bone mass and compared them to normal premenopausal women with respect to serum concentrations of IGF-I. Thirteen premenopausal women (34.2+/-2.3 years) with low bone density (mean lumbar spine T-score -2.26+/-0.20) were compared with 13 premenopausal women (35.7+/-1.7 years) with normal bone density of similar age, height and ethnic composition. Body mass index (BMI) was lower in subjects than controls (20.5+/-0.7 versus 25.2+/-1.1 kg/m(2), P<0.01). A family history of osteoporosis and a history of fragility fractures were found more frequently in subjects than controls (P< or =0.05). Calciotropic hormones did not differ between the two groups. In contrast to our observations in men with idiopathic osteoporosis, mean serum IGF-I concentrations did not differ between subjects and controls (subjects: 22.5+/-2.2 nmol/l versus controls: 20.8+/-1.6 nmol/l; NS). Moreover, serum IGF-I levels did not correlate significantly with serum estradiol or with BMD at either the lumbar spine or femoral neck. However, lower follicular phase serum estradiol levels among non-oral contraceptive users were found in subjects as compared to controls (subjects: 124.1+/-13 pmol/l versus controls 194.9+/-24 pmol/l, P=0.06). Calculated free, bioavailable estradiol levels were significantly lower overall in subjects than controls (0.6+/-0.1 versus 1.2+/-0.2 pmol/l, P<0.05). Total serum estradiol levels correlated with BMD at the femoral neck (r=+0.50; P<0.05). Free, bioavailable estradiol correlated with BMD and BMAD at the lumbar spine (r=+0.54, P<0.01 and r=+0.54, P<0.05, respectively) and femoral neck (r=+0.60 and r=+0.55 respectively, both P<0.01). Urinary NTX excretion, although within the normal premenopausal range, was 45% higher in subjects than controls (41.6+/-5.9 nmol BCE/l versus 28.3+/-2.4 nmol BCE/l; P<0.05). Bone-specific alkaline phosphatase activity was also higher (17.4+/-1.6 ng/ml versus 14.7+/-0.8 ng/ml), although the difference was not statistically significant. These results suggest differences in the pathogenesis of idiopathic osteoporosis in women as compared to men with IOP.

Management of Low Bone Mineral Density in Premenopausal Women

OBJECTIVE

To review evidence for management of low bone density in premenopausal women and to establish practical guidelines for management of low bone density in this population by family physicians.

METHOD

A search of MEDLINE for relevant articles published between January 1990 and May 2004 was conducted. Articles retrieved were graded by level of evidence. Recommendations for diagnosis and therapy were based on evidence from randomized controlled trials and expert consensus.

RESULTS

Low bone density in premenopausal women is not associated with the same increased risk of fracture seen in older women. In the absence of fragility fractures and loss of height, it may be a reflection of low peak bone mass and may represent the normal variation in bone mineral density (BMD). Women may have low bone density secondary to an underlying skeletal or systemic disorder. Common causes of low bone density in premenopausal women include ovulatory disturbances and low body weight.

CONCLUSION

Osteoporosis is diagnosed in the premenopausal female population in the presence of fragility fractures and is not based solely on the results of BMD testing. Secondary causes of bone loss should be excluded, and any underlying condition contributing to low bone density should be corrected. Antiresorptive therapy has been evaluated only in those premenopausal women who are on glucocorticoid therapy and in those with primary hyperparathyroidism. Only in these conditions has antiresorptive therapy been shown to improve BMD.

Physiological aspects and clinical sequelae of energy deficiency and hypoestrogenism in exercising women

Amenorrhoea associated with reduced caloric intake and strenuous exercise leads to hypoestrogenism and is associated with clinical manifestations that include disordered eating, stress fractures, osteoporosis, and, as recently reported, a potential increase in the risk of premature cardiovascular disease. Disordered eating, menstrual irregularities and bone loss comprise the clinical condition known as the 'female athlete triad'. The aetiology of the triad is linked to a high prevalence of disordered eating and cognitive restraint. This results in inadequate caloric intake for high exercise energy expenditures that leads to energy deficiency. This in turn stimulates compensatory mechanisms, such as weight loss or energy conservation, subsequently causing a central suppression of reproductive function and concomitant hypoestrogenism. Because the aetiology of menstrual disturbances and the female athlete triad is causally linked to energy deficiency, there is no justification for fears that exercise itself is unhealthy for women. However, improved detection, monitoring, and treatment of all components of the triad in exercising women should be emphasized. This paper critically reviews the physiological aspects and clinical sequelae of energy deficiency and hypoestrogenism associated with the female athlete triad in exercising women.

Bone densitometry in premenopausal women: synthesis and review

Bone loss prior to menopause is being increasingly identified in women. Clearly, low bone mineral density (BMD) is a significant risk factor for fracture in the estrogen-deficient female postmenopause. The significance of low bone density prior to menopause needs to be addressed. Low bone density in the premenopausal female may reflect attainment of a lower peak bone mass. It may also be secondary to progressive bone loss following achievement of peak bone density. The etiology of low bone density in the premenopausal female needs to be clarified with meticulous exclusion of secondary causes of bone loss. Menstrual status is an important determinant of peak bone mass as well as the development of bone loss in women prior to the onset of menopause. Subclinical decreases in circulating gonadal steroids may be associated with a lower peak bone mass as well as progressive bone loss in otherwise reproductively normal women. Elevations of follicle-stimulating hormone (FSH) of greater than 20 miu/L are associated with evidence of increased bone turnover marker activity and correlate with progressive bone loss in perimenopausal women. This transitional period requires further study with respect to the magnitude of bone loss experienced and the potential benefits of antiresorptive therapy. Detailed assessment of menstrual status is necessary in the evaluation of low bone density in premenopausal women. The majority of the cross-sectional and longitudinal studies completed evaluating BMD in the premenopausal years suggest that minimal bone loss does occur prior to menopause after attainment of peak bone mass. The magnitude of premenopausal bone loss, however, is controversial and may be site-dependent. More rapid rates of bone loss are seen in the transitional period beginning 2-3 yr prior to the onset of menopause. Prospective data are needed to understand further the relationship between BMD and fracture in the premenopausal period. Women with steroid-induced bone loss as well as other secondary causes of osteoporosis respond to antiresorptive therapy with documented improvements in BMD. Biomarkers can identify perimenopausal women with increased bone turnover. Lifestyle modification can improve BMD in the pre- and the perimenopausal period. Antiresorptive therapy has not been evaluated in pre- or perimenopausal women with low BMD in the absence of secondary causes of osteoporosis. As new treatment options are evaluated and become available, biomarker assessment may be of value in identifying women at risk of fracture.

Ovarian Dysfunction, Stress, and Disease: A Primate Continuum

Menopause is recognized as a period of increased risk for coronary heart disease (CHD) and osteoporosis. Vulnerability to these conditions is often attributed to the naturally occurring estrogen deficiency characteristic of this part of the life cycle. Premenopausal reductions in endogenous estrogen occasioned by functional ovarian abnormalities or failure are hypothesized to be similarly pathogenic and to accelerate development of CHD and osteoporosis prematurely, thereby increasing the health burden of older women. These functional abnormalities, which occur along a continuum from mild, luteal phase progesterone deficiency to amenorrhea, are relatively common and are often attributed to psychogenic factors (stress, anxiety, depression, or other emotional disturbance), exercise, or energy imbalance. Although numerous investigators have commented on these functional deficits, the abnormalities can be difficult to diagnose and are generally unappreciated for the contribution they may make to postmenopausal disease. Studies in nonhuman primates confirm that these deficits are easily induced by psychological stress and exercise, and that they accelerate the development of cardiovascular disease and perhaps bone loss in the presence of a typical North American diet. However, functional reproductive deficits are also reversible and are thus potentially amenable to environmental or behavioral intervention. Data from both women and nonhuman primates support the hypothesis that functional reproductive deficits are adaptive when triggered appropriately but are detrimental when activated in an environment (e.g., sedentary lifestyle, high-fat diet) permissive to the development of chronic disease.

Assessing menstrual cycles with urinary hormone assays

The Study of Women's Health Across the Nation (SWAN) is a multiethnic cohort study of middle-aged women enrolled at seven US sites. A subset of 848 women completed a substudy in which their urinary gonadotropins and sex steroid metabolites were assessed during one complete menstrual cycle or up to 50 consecutive days. Urine was analyzed for LH, FSH, estrone conjugates (E1c), and pregnanediol glucuronide (Pdg). To prepare for serial analysis of this large, longitudinal database in a population of reproductively aging women, we examined the performance of algorithms designed to identify features of the normal menstrual cycle in midreproductive life. Algorithms were based on existing methods and were compared with a "gold standard" of ratings of trained observers on a subset of 396 cycles from the first collection of Daily Hormone Substudy samples. In evaluating luteal status, overall agreement between and within raters was high. Only 17 of the 396 cycles evaluated were considered indeterminate. Of the 328 cycles rated as containing evidence of luteal activity (ELA), 320 were considered ELA by use of a Pdg threshold detection algorithm. Of 51 cycles that were rated as no evidence of luteal activity, only 2 were identified by this algorithm as ELA. Evaluation of the day of the luteal transition with methods that detected a change in the ratio of E1c to Pdg provided 85-92% agreement for day of the luteal transition within 3 days of the raters. Adding further conditions to the algorithm increased agreement only slightly, by 1-8%. We conclude that reliable, robust, and relatively simple objective methods of evaluation of the probability and timing of ovulation can be used with urinary hormonal assays in early perimenopausal women.

Follicle stimulating hormone measured in unextracted urine throughout the menstrual cycle correlates with age and ovarian reserve

BACKGROUND

A method was previously described to measure FSH reliably in unextracted urine. The aim of the current study was to establish the course of FSH measured in urine throughout the cycle.

METHOD

Daily urinary FSH (uFSH) concentrations were determined in 14 regularly menstruating volunteers aged 23-39 years during one complete menstrual cycle.

RESULTS

In each subject, mean daily uFSH measured in urine, as gold standard for FSH tone, correlated significantly with FSH in early follicular phase fixed to menstruation on cycle day 3 (r = 0.75, P = 0.002), or fixed to ovulation 9 days before the pre-ovulatory FSH surge (r = 0.87, P = 0.0001), or when selected as being the highest follicular phase value (r = 0.91, P = 0.0001). Age correlated significantly with mean daily uFSH (r = 0.67, P = 0.009), highest follicular phase uFSH (r = 0.60, P = 0.024), uFSH on cycle day 3 (r = 0.80, P = 0.0006), and uFSH 9 days before FSH surge (r = 0.65, P = 0.0016). The uFSH was also measured on cycle day 3 in 104 IVF patients in a cycle prior to pituitary down-regulation. The uFSH correlated significantly with numbers of follicles (P = 0.02) and oocytes (P = 0.024).

CONCLUSION

It is concluded that cycle day 3 uFSH is a good reflection of the mean uFSH of the complete cycle, and there is a highly significant correlation between uFSH and age and ovarian reserve. Measurement of FSH in urine on cycle day 3 seems to be a reliable and non-invasive tool for determining ovarian reserve in IVF.

Energetic factors, ovarian steroids and the risk of breast cancer

In industrial countries, women often have excess metabolic energy due to high food consumption and low physical activity. High lifetime energy availability results in high lifetime levels of ovarian steroid hormones. Oestrogens and progesterone are hypothesized to play a crucial role in the development and prognosis of breast cancer. Epidemiological studies document the importance of physical activity and caloric limitations in reducing breast cancer risk. The risk of breast cancer is much higher in industrial countries than in developing countries, where women are characterized by lower energy intake and higher energy expenditure. It is likely, that the beneficial effects of physical activity and of negative energy balance are mediated by the reduced levels of ovarian steroids. While both weight loss and physical activity may have similar efficacy in suppressing ovarian function and, therefore, in reducing the risk of breast cancer, we suggest that it may be more advantageous for premenstrual women to achieve lifetime reduction in steroid levels by increasing their physical activity, rather than by weight loss due to caloric restriction alone.

Osteoporosis and low bone mass in premenopausal and perimenopausal women

OBJECTIVE

To characterize the historical, clinical, and biochemical features of 111 young women (age, <55 years) referred for evaluation of osteoporosis or low bone mass.

METHODS

Women with a bone mineral density T score < or = -2.0 (N = 111) at one or more anatomic sites (by dual-energy x-ray absorptiometry) were assessed relative to anthropomorphic and biochemical characteristics and risk factors for osteoporosis.

RESULTS

Of 111 women with low bone mass or osteoporosis, 73 (66%) had identifiable causes of bone loss, of which estrogen deficiency (menopause, premenopausal estrogen deficiency) and conditions associated with estrogen deficiency (anorexia nervosa, cancer chemotherapy) were the most common. Prolonged use of glucocorticoids was the most common secondary cause of osteoporosis. Of 38 women with no identifiable cause of bone loss, 21 were premenopausal (mean age, 38 +/- 10 years [standard deviation]) and 17 were perimenopausal (mean age, 50 +/- 3 years). The mean lumbar spine T score was -2.18 +/- 1.0 in the premenopausal and -2.51 +/- 0.6 in the perimenopausal women. Nontraumatic fractures were reported by 42% of the premenopausal women and 18% of the perimenopausal women. A family history of osteoporosis was reported by 71% of the premenopausal and 47% of the perimenopausal women.

CONCLUSION

Most young women with osteoporosis or low bone mass had estrogen deficiency or another secondary cause of premature bone loss (or both). A subset of premenopausal and perimenopausal women, however, had no identifiable cause of bone loss. The strong family history of osteoporosis, especially in the premenopausal women, provides further support for current theories of a genetic predisposition to osteoporosis.