Improving Prediction of Age at Menopause Using Multiple Anti-Müllerian Hormone Measurements: the Tehran Lipid-Glucose Study

Association between anti-mullerian hormone and metabolic syndrome: insights from a prospective community-based study

BACKGROUND

Limited studies have investigated the relationship between Anti-Müllerian hormone (AMH) and metabolic syndrome (MetS), yielding inconclusive results. This study aimed to examine the relationship between AMH levels and MetS and its components in women from a general population.

METHODS

This prospective study recruited 769 women. Generalized Estimating Equation (GEE) models analyzed longitudinal trends of MetS components. Cox proportional hazard models evaluated effect of age-specific AMH tertiles on MetS occurrence, adjusting for confounders.

RESULTS

The GEE analysis indicated that women in the third tertile exhibited higher mean FPG compared to those in the first tertile of age-specific AMH (3 mg/dL; 95% CI: 0.40, 5.60; P = 0.024); however, this association became non-significant after adjustment. Notably, the second tertile showed a significant decrease in FPG mean changes over time (-0.69 mg/dL; 95% CI: -1.31, -0.07; P Interaction = 0.030). Women in the second and third tertiles of age-specific AMH demonstrated lower mean HDL-C compared to the first tertile (-2.96 mg/dL; 95% CI: -4.67, -1.26; P < 0.001 and -2.63 mg/dL; 95% CI: -4.31, -0.96; P = 0.002, respectively). The association between HDL-C changes and the second tertile remained significant after adjustment (-1.91 mg/dL; 95% CI: -3.68, -0.14; P = 0.034). No significant associations were observed between age-specific AMH tertiles and TG and SBP/DBP. Cox models revealed no significant differences in the hazard ratio of MetS between AMH tertiles after adjusting for confounders.

CONCLUSION

Despite minor variations in MetS components, AMH levels did not affect MetS risk in women from a general population.

Associations of anti-Müllerian hormone levels among women in their mid-30s with menopausal symptoms ~14 years later

OBJECTIVE

The aim of this study was to examine associations of anti-Müllerian hormone (AMH) levels in gravid women in their mid-30s with menopausal symptoms ~14 years later and age at natural menopause.

METHODS

In this prospective analysis, 474 participants in Project Viva, a longitudinal cohort, were enrolled during pregnancy between 1999 and 2002. AMH levels were determined using plasma samples collected 3 years postpartum. Participants completed the Menopause Rating Scale (MRS) and self-reported age at and reason for menopause at the 17 years postpartum visit (Mid-Life Visit). Primary outcomes were individual MRS item responses and total MRS score. To examine associations between AMH levels and menopausal outcomes, we performed linear and logistic regressions, and survival analyses, adjusting for confounding variables.

RESULTS

Mean (SD) AMH level was 2.80 (2.74) ng/mL, measured at 38.2 (3.9) years. At the Mid-Life Visit, mean (SD) age was 52.3 (3.9) years and total MRS score was 8.0 (5.7). During follow-up, 50% had experienced natural menopause, and self-reported mean (SD) age at natural menopause was 50.4 (3.6) years. AMH in the lowest tertile (mean [SD]: 0.47 [0.32] ng/mL) was associated with higher odds of moderate to severe vaginal dryness (adjusted odds ratio: 2.58; 95% CI: 1.16 to 5.73), a lower MRS psychological subscale (adjusted β: -0.71; 95% CI: -1.35 to -0.07), and earlier attainment of natural menopause (adjusted hazards ratio: 7.1; 95% CI: 4.6 to 11.0) compared with AMH in the highest tertile (mean [SD]: 6.01 [2.37] ng/mL).

CONCLUSIONS

Lower AMH in the mid-30s was associated with earlier menopause and increased odds of vaginal dryness but fewer psychological symptoms ~14 years later.

Can we predict menopause and premature ovarian insufficiency?

The prediction of menopause and premature ovarian insufficiency (POI) involves understanding the factors that contribute to the timing of these events. Menopause is a natural biological process marked by the cessation of menstrual periods, typically occurring around the age of 51. On the other hand, POI refers to the loss of ovarian function before the age of 40. Several factors have been used to predict menopause and POI such as age, antimüllerian hormone, inhibins and follicle-stimulating hormone serum levels, antral follicle counts, menstrual cycle length, and, recently, some genetic markers. It seems that age has the best predictive power and all the other ones are only adding in a very limited way to the prediction of menopause. Low levels of antimüllerian hormone in young women might indicate a greater risk for POI and could facilitate early diagnosis. It is, however, important to note that predicting the exact timing of menopause and POI is challenging, and individual variations are significant. Although these factors can provide some insights, they are not foolproof predictors. Advances in medical research and technology may lead to more accurate methods for predicting menopause and POI in the future.

Association between neighborhood poverty and ovarian reserve: the ovarian aging study

OBJECTIVE

This study aimed to examine the association between neighborhood poverty and ovarian reserve.

METHODS

Among 1,019 healthy premenopausal women in the Ovarian Aging Study, aggregate exposure to neighborhood poverty was examined in relation to biomarkers of ovarian reserve, antimüllerian hormone (AMH) and antral follicle count (AFC). Specifically, the interaction of age-x-neighborhood poverty was assessed cross-sectionally to determine whether AMH and AFC declines across women may be greater in women exposed to more neighborhood poverty. Neighborhood poverty was assessed by geocoding and linking women's residential addresses in adulthood to US Census data.

RESULTS

Independent of covariates, a significant interaction term showed the association between age and AMH varied by degree of exposure to neighborhood poverty in adulthood ( b = -0.001, P < 0.05). AMH declines increased progressively across women exposed to low, medium, and high levels of neighborhood poverty. In addition, main effects showed that higher neighborhood poverty was related to higher AMH in the younger women only ( b = 0.022, P < 0.01). Results related to AFC were all nonsignificant ( P > 0.05).

CONCLUSIONS

Across women, greater aggregate exposure to neighborhood poverty in adulthood was related to lower ovarian reserve, indexed by AMH. In addition, there was a positive association between neighborhood poverty and AMH in younger women that attenuated in the older women. Together, results suggest that neighborhood disadvantage may have detrimental impacts that manifest as initially higher AMH, resulting in greater ovarian follicle loss over time. However, it remains unclear whether these results examining differences across women may replicate when AMH declines by neighborhood poverty are examined longitudinally.

Anti-Mullerian hormone and cardiometabolic status: a systematic review

BACKGROUND

To summarise the relationship between Anti-mullerian hormone (AMH) levels and cardiometabolic status in different populations.

METHODS

PubMed, Scopus, and Embase were searched for retrieving observational studies published up to February 2022 investigating the relationship between AMH level and cardiometabolic status.

RESULTS

Of 3,643 studies retrieved from databases, a total of 37 observational studies were included in this review. The majority of the included studies revealed an inverse association between AMH and lipid profiles, including triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL), and a positive correlation with high-density lipoprotein (HDL). While some studies have revealed a significant inverse association between AMH and glycemic parameters, including fasting plasma glucose (FPG), fasting insulin, and HOMA-IR, others found no such relationships. There is also an inconsistency among studies regarding the association of AMH with adiposity indices and blood pressure. Evidence indicates a significant association between AMH and some vascular markers, such as intima-media thickness and coronary artery calcification. Of 3 studies evaluating the relationship between AMH and cardiovascular events, two studies showed an inverse relationship between AMH levels and cardiovascular (CVD), whereas another study showed no significant association.

CONCLUSIONS

The results of this systematic review suggest that serum AMH levels can be associated with CVD risk. This may provide new insight into the use of AMH concentrations as a predictive marker for assessing the risk of cardiovascular disease, although more well-design longitudinal studies are still necessary for this area. Future studies on this topic will hopefully provide an opportunity to run a meta-analysis; it will increase the persuasiveness of this interpretation.

Anti-Müllerian hormone for the diagnosis and prediction of menopause: a systematic review

BACKGROUND

The early onset of menopause is associated with increased risks of cardiovascular disease and osteoporosis. As a woman's circulating anti-Müllerian hormone (AMH) concentration reflects the number of follicles remaining in the ovary and declines towards the menopause, serum AMH may be of value in the early diagnosis and prediction of age at menopause.

OBJECTIVE AND RATIONALE

This systematic review was undertaken to determine whether there is evidence to support the use of AMH alone, or in conjunction with other markers, to diagnose menopause, to predict menopause, or to predict and/or diagnose premature ovarian insufficiency (POI).

SEARCH METHODS

A systematic literature search for publications reporting on AMH in relation to menopause or POI was conducted in PubMed®, Embase®, and the Cochrane Central Register of Controlled Trials up to 31 May 2022. Data were extracted and synthesized using the Synthesis Without Meta-analysis for diagnosis of menopause, prediction of menopause, prediction of menopause with a single/repeat measurement of AMH, validation of prediction models, short-term prediction in perimenopausal women, and diagnosis and prediction of POI. Risk-of-bias was evaluated using the Tool to Assess Risk of Bias in Cohort Studies protocol and studies at high risk of bias were excluded.

OUTCOMES

A total of 3207 studies were identified, and 41, including 28 858 women, were deemed relevant and included. Of the three studies that assessed AMH for the diagnosis of menopause, one showed that undetectable AMH had equivalent diagnostic accuracy to elevated FSH (>22.3 mIU/ml). No study assessed whether AMH could be used to shorten the 12 months of amenorrhoea required for a formal diagnosis of menopause. Studies assessing AMH with the onset of menopause (27 publications [n = 23 835 women]) generally indicated that lower age-specific AMH concentrations are associated with an earlier age at menopause. However, AMH alone could not be used to predict age at menopause with precision (with estimates and CIs ranging from 2 to 12 years for women aged <40 years). The predictive value of AMH increased with age, as the interval of prediction (time to menopause) shortened. There was evidence that undetectable, or extremely low AMH, may aid early diagnosis of POI in young women with a family history of POI, and women presenting with primary or secondary amenorrhoea (11 studies [n = 4537]).

WIDER IMPLICATIONS

The findings of this systematic review support the use of serum AMH to study the age of menopause in population studies. The increased sensitivity of current AMH assays provides improved accuracy for the prediction of imminent menopause, but diagnostic use for individual patients has not been rigorously examined. Prediction of age at menopause remains imprecise when it is not imminent, although the finding of very low AMH values in young women is both of clinical value in indicating an increased risk of developing POI and may facilitate timely diagnosis.

Age-specific random day serum antimüllerian hormone reference values for women of reproductive age in the general population: a large Chinese nationwide population-based survey

BACKGROUND

Antimüllerian hormone, the most reliable biomarker of ovarian reserve, is widely used in various clinical situations. Antimüllerian hormone levels consistently decrease with age. However, there is no standard, age-specific reference values for antimüllerian hormone in women of reproductive age, which limits its application.

OBJECTIVE

This study aimed to establish age-specific antimüllerian hormone percentile reference values for women of reproductive age.

STUDY DESIGN

A nationwide, population-based cross-sectional survey was conducted between May 2019 and April 2021 in 15 provinces and municipalities in mainland China. A total of 10,053 eligible women aged 20 to 49 years were selected using a multistage stratified sampling procedure. Women who were pregnant, had undergone ovarian surgery, took hormone drugs in the past 3 months, or had an antimüllerian hormone outlier value were excluded from establishing antimüllerian hormone percentile reference values. Serum antimüllerian hormone concentrations were measured using ultrasensitive, 2-site enzyme-linked immunosorbent assays (Ansh Lab, Webster, TX) in the Reproductive Endocrinology Laboratory of Peking University Third Hospital. Generalized additive models for location scale and shape with the Box-Cox t original distribution were used to estimate the fitted antimüllerian hormone percentile reference values.

RESULTS

A total of 9112 eligible women aged 21 to 49 years were included in the fitting model. The fitted 50th (2.5th-97.5th) percentiles of antimüllerian hormone values for women aged 21, 25, 30, 35, 40, 45, and 49 years were 4.83 (0.79-18.41), 4.47 (0.72-16.58), 3.67 (0.50-13.82), 2.59 (0.24-10.35), 1.35 (0.05-6.68), 0.33 (<0.01 to 3.40), and 0.04 (<0.01 to 1.77) ng/mL, respectively. The population-based decline rate of antimüllerian hormone accelerated with increasing age, especially age >35 years. The magnitude of the decline of the 25th antimüllerian hormone percentile curve was greater than that of the 75th percentile curve.

CONCLUSION

This study established age-specific antimüllerian hormone percentile reference values for women of reproductive age based on a large representative sample of the general population and described antimüllerian hormone changes. These findings may facilitate antimüllerian hormone application in clinical practices.

Risk Prediction Models of Natural Menopause Onset: A Systematic Review

CONTEXT

Predicting the onset of menopause is important for family planning and to ensure prompt intervention in women at risk of developing menopause-related diseases.

OBJECTIVE

We aimed to summarize risk prediction models of natural menopause onset and their performance.

METHODS

Five bibliographic databases were searched up to March 2022. We included prospective studies on perimenopausal women or women in menopausal transition that reported either a univariable or multivariable model for risk prediction of natural menopause onset. Two authors independently extracted data according to the CHARMS (critical appraisal and data extraction for systematic reviews of prediction modelling studies) checklist. Risk of bias was assessed using a prediction model risk of bias assessment tool (PROBAST).

RESULTS

Of 8132 references identified, we included 14 articles based on 8 unique studies comprising 9588 women (mainly Caucasian) and 3289 natural menopause events. All included studies used onset of natural menopause (ONM) as outcome, while 4 studies also predicted early ONM. Overall, there were 180 risk prediction models investigated, with age, anti-Müllerian hormone, and follicle-stimulating hormone being the most investigated predictors. Estimated C-statistic for the prediction models ranged from 0.62 to 0.95. Although all studies were rated at high risk of bias mainly due to the methodological concerns related to the statistical analysis, their applicability was satisfactory.

CONCLUSION

Predictive performance and generalizability of current prediction models on ONM is limited given that these models were generated from studies at high risk of bias and from specific populations/ethnicities. Although in certain settings such models may be useful, efforts to improve their performance are needed as use becomes more widespread.

Anti-Müllerian hormone as a marker of ovarian reserve and premature ovarian insufficiency in children and women with cancer: a systematic review

BACKGROUND

Female patients undergoing anticancer treatment are at elevated risk of adverse ovarian outcomes including infertility and premature ovarian insufficiency (POI), which is associated with short- and long-term health risks. Anti-Müllerian hormone (AMH) is a key biomarker of ovarian reserve, but its role prior to and after cancer treatment is less well understood.

OBJECTIVE AND RATIONALE

To conduct a systematic review evaluating AMH as a biomarker of ovarian reserve and POI before and after anticancer treatment, which has become a pressing clinical issue in reproductive medicine. There are a large number of observational studies, but differences in patient groups, cancer diagnoses and study design make this a confusing field that will benefit from a thorough and robust review.

SEARCH METHODS

A systematic literature search for AMH in women with cancer was conducted in PubMed, Embase and Cochrane Central Register of Controlled Trials up to 1 April 2021. Bias review was conducted using the Risk of Bias In Non-randomized Studies of Interventions (ROBINS-I) protocol along with qualitative assessment of quality. Exploratory subgroups were established based on age, cancer type and length of follow-up.

OUTCOMES

Ninety-two publications (N = 9183 patients) were included in this analysis after quality and bias review. Reduced/undetectable AMH was consistently identified in 69/75 studies (92%) following chemotherapy or radiotherapy, with reductions ranging from 42% to concentrations below the limit of detection, and many reporting mean or median declines of ≥90%. Where longitudinal data were analysed (42 studies), a majority (33/42 (79%)) of studies reported at least partial recovery of AMH at follow-up, however, effect estimates were highly variable, reflecting that AMH levels were strongly impacted by anticancer treatment (i.e. the chemotherapy regimen used and the number of treatment cycles need), with recovery and its degree determined by treatment regimen, age and pre-treatment AMH level. In 16/31 (52%) publications, oligo/amenorrhoea was associated with lower post-treatment AMH consistent with impending POI, although menstruation and/or pregnancy were reported in patients with low or undetectable AMH. Long-term (>5 years) follow-up of paediatric patients following cancer treatment also found significantly lower AMH compared with control groups in 14/20 (70%) of studies, with very variable effect sizes from complete loss of AMH to full recovery depending on treatment exposure, as in adult patients.

WIDER IMPLICATIONS

AMH can be used to identify the damaging effect of cancer treatments on ovarian function. This can be applied to individual women, including pre-pubertal and adolescent girls, as well as comparing different treatment regimens, ages and pre-treatment AMH levels in populations of women. While there was evidence for its value in the diagnosis of POI after cancer treatment, further studies across a range of diagnoses/treatment regimens and patient ages are required to clarify this, and to quantify its predictive value. A major limitation for the use of AMH clinically is the very limited data relating post-treatment AMH levels to fertility, duration of reproductive lifespan or time to POI; analysis of these clinically relevant outcomes will be important in further research.

Can time to menopause be predicted?

Menopause represents the definite end of a woman's reproductive life and the onset of a persistent hypoestrogenic state. This postmenopausal period will for most women last several decades. Although mean menopausal age seems to have increased somewhat during the last century, there is a significant individual variation in age at natural menopause. With efficient contraception, women of reproductive age can now, to some extent, choose when they want to have children. As a consequence of this and other sociodemographic changes, age at first birth has increased significantly over the last 50 years. It is well documented that long before a woman enters the menopausal transition and subsequent menopause, fertility declines and finally ceases. Being able to predict when a woman will enter menopause would therefore, from a reproductive perspective, be of major interest. Several sociodemographic, morphometric, and endocrine factors are associated with age at menopause or time to menopause. Unfortunately the sensitivity and specificity of these in predicting time to or age at menopause are low. Therefore, with the exception of anti-Müllerian hormone measurements, either alone or in combination with chronological age close to menopause, there are as of now no reliable ways of predicting when a woman will enter menopause.

Serum metabolomics study of women with different annual decline rates of anti-Müllerian hormone: an untargeted gas chromatography-mass spectrometry-based study

STUDY QUESTION

Which metabolites are associated with varying rates of ovarian aging, measured as annual decline rates of anti-Müllerian hormone (AMH) concentrations?

SUMMARY ANSWER

Higher serum concentrations of metabolites of phosphate, N-acetyl-d-glucosamine, branched chained amino acids (BCAAs), proline, urea and pyroglutamic acid were associated with higher odds of fast annual decline rate of AMH.

WHAT IS KNOWN ALREADY

Age-related rate of ovarian follicular loss varies among women, and the factors underlying such inter-individual variations are mainly unknown. The rate of ovarian aging is clinically important due to its effects on both reproduction and health of women. Metabolomics, a global investigation of metabolites in biological samples, provides an opportunity to study metabolites or metabolic pathways in relation to a physiological/pathophysiological condition. To date, no metabolomics study has been conducted regarding the differences in the rates of ovarian follicular loss.

STUDY DESIGN, SIZE, DURATION

This prospective study was conducted on 186 reproductive-aged women with regular menstrual cycles and history of natural fertility, randomly selected using random case selection option in SPSS from the Tehran Lipid and Glucose Study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

AMH concentrations were measured at baseline (1999-2001) and the fifth follow-up examination (2014-2017), after a median follow-up of 16 years, by immunoassay using Gen II kit. The annual decline rate of AMH was calculated by dividing the AMH decline rate by the follow-up duration (percent/year). The women were categorized based on the tertiles of the annual decline rates. Untargeted metabolomics analysis of the fasting-serum samples collected during the second follow-up examination cycle (2005-2008) was performed using gas chromatography-mass spectrometry. A combination of univariate and multivariate approaches was used to investigate the associations between metabolites and the annual decline rates of AMH.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjusting the baseline values of age, AMH and BMI, 29 metabolites were positively correlated with the annual AMH decline rates. The comparisons among the tertiles of the annual decline rate of AMH revealed an increase in the relative abundance of 15 metabolites in the women with a fast decline (tertile 3), compared to those with a slow decline (tertile 1). There was no distinct separation between women with slow and fast decline rates while considering 41 metabolites simultaneously using the principal component analysis and the partial least-squares discriminant analysis models. The odds of fast AMH decline was increased with higher serum metabolites of phosphate, N-acetyl-d-glucosamine, BCAAs, proline, urea and pyroglutamic acid. Amino sugar and nucleotide sugar metabolism, BCAAs metabolism and aminoacyl tRNA biosynthesis were among the most significant pathways associated with the fast decline rate of AMH.

LIMITATIONS, REASONS FOR CAUTION

Estimating the annual decline rates of AMH using the only two measures of AMH is the main limitation of the study which assumes a linear fixed reduction in AMH during the study. Since using the two-time points did not account for the variability in the decline rate of AMH, the annual decline rates estimated in this study may not accurately show the trend of the reduction in AMH. In addition, despite the longitudinal nature of the study and statistical adjustment of the participants' ages, it is difficult to distinguish the AMH-related metabolites observed in this study can accelerate ovarian aging or they are reflections of different rates of the aging process.

WIDER IMPLICATIONS OF THE FINDINGS

Some metabolite features related to the decline rates of AMH have been suggested in this study; further prospective studies with multiple measurements of AMH are needed to confirm the findings of this study and to better understand the molecular process underlying variations in ovarian aging.

STUDY FUNDING/COMPETING INTEREST(S)

This study, as a part of PhD thesis of Ms Nazanin Moslehi, was supported by Shahid Beheshti University of Medical Sciences (10522-4). There were no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Challenges in Measuring AMH in the Clinical Setting

Serum anti-Mullerian hormone (AMH) is a widely used marker of functional ovarian reserve in the assessment and treatment of infertility. It is used to determine dosing of gonadotropins used for superovulation prior to in vitro fertilization, as well as to determine the degree of damage to ovarian reserve by cytotoxic treatments such as chemotherapy. AMH is also now used to predict proximity to menopause and potentially provides a sensitive and specific test for polycystic ovarian syndrome. Twenty one different AMH immunoassay platforms/methods are now commercially available. Of those compared, the random-access platforms are the most reliable. However, to date there has not been an agreed common international AMH reference preparation to standardize calibration between the various immunoassays. Recently, a purified human AMH preparation (code 16/190) has been investigated by the World Health Organization as a potential international reference preparation. However, this was only partially successful as commutability between it and serum samples was observed only in some but not all immunoassay methods. Development of a second generation reference preparation with wider commutability is proposed.

The association between the levels of anti-Müllerian hormone (AMH) and dietary intake in Iranian women

PURPOSE

This paper aimed to assess the association between AMH with dietary intake of adult women referred to the infertility clinic of Al-Zahra Hospital in Rasht, Iran.

METHODS

This cross-sectional study was performed on 234 adult women referred to the infertility clinic of Al-Zahra Hospital, Rasht, Iran. The participants were categorized into two groups based on their AMH levels. Participants' data on lifestyle and anthropometry as well as blood samples were collected. Dietary intakes were assessed by a validated food frequency questionnaire (FFQ).

RESULTS

Serum AMH concentration was negatively associated with the intake of fast foods (P = 0.002) and saturated fats (P = 0.040). These associations remained significant after adjustments for age, rural or urban location, and education. Additional adjustments for body mass index (BMI) and physical activity did not change the results. The results remained significant after further adjustments for menstrual age, menstrual pattern, and oral contraceptive pills.

CONCLUSION

Fast foods and saturated fats were significantly associated with lower AMH concentrations and modifying the amount of these dietary components may be an important strategy for increasing the reservation of ovaries in women. Future longitudinal studies are warranted to confirm these findings and to identify the underlying mechanisms.

Age-specific cut-off levels of anti-Müllerian hormone can be used as diagnostic markers for polycystic ovary syndrome

BACKGROUND

The majority of available studies on the AMH thresholds were not age-specific and performed the receiver operating characteristic curve (ROC) analysis, based on variations in sensitivity and specificity rather than positive and negative predictive values (PPV and NPV, respectively), which are more clinically applicable. Moreover, all of these studies used a pre-specified age categorization to report the age-specific cut-off values of AMH.

METHODS

A total of 803 women, including 303 PCOS patients and 500 eumenorrheic non-hirsute control women, were enrolled in the present study. The PCOS group included PCOS women, aged 20-40 years, who were referred to the Reproductive Endocrinology Research Center, Tehran, Iran. The Rotterdam consensus criteria were used for diagnosis of PCOS. The control group was selected among women, aged 20-40 years, who participated in Tehran Lipid and Glucose cohort Study (TLGS). Generalized additive models (GAMs) were used to identify the optimal cut-off points for various age categories. The cut-off levels of AMH in different age categories were estimated, using the Bayesian method.

MAIN RESULTS AND THE ROLE OF CHANCE

Two optimal cut-off levels of AMH (ng/ml) were identified at the age of 27 and 35 years, based on GAMs. The cut-off levels for the prediction of PCOS in the age categories of 20-27, 27-35, and 35-40 years were 5.7 (95 % CI: 5.48-6.19), 4.55 (95 % CI: 4.52-4.64), and 3.72 (95 % CI: 3.55-3.80), respectively. Based on the Bayesian method, the PPV and NPV of these cut-off levels were as follows: PPV = 0.98 (95 % CI: 0.96-0.99) and NPV = 0.40 (95 % CI: 0.30-0.51) for the age group of 20-27 years; PPV = 0.96 (95 % CI: 0.91-0.99) and NPV = 0.82 (95 % CI: 0.78-0.86) for the age group of 27-35 years; and PPV = 0.86 (95 % CI: 0.80-0.94) and NPV = 0.96 (95 % CI: 0.93-0.98) for the age group of 35-40 years.

CONCLUSIONS

Application of age-specific cut-off levels of AMH, according to the GAMs and Bayesian method, could elegantly assess the value of AMH in discriminating PCOS patients in all age categories.

Prediction of premature ovarian insufficiency: foolish fallacy or feasible foresight?

Prediction of premature ovarian insufficiency (POI) would be of substantial individual benefit, but being a heterogeneous and fluctuating condition, with an extensive range of complex etiologies and arbitrary diagnostic criteria, might make this seem foolhardy. However, contemporary and complementary genetic strategies assessing consanguineous and large POI pedigrees and cohorts with age at natural menopause have shown strong enrichment in genes regulating DNA damage repair, homologous recombination, and meiosis, processes that are critical to oogenesis and folliculogenesis. Recognition of the molecular architecture of POI and its contribution to baseline genotypic risk may enable these estimates to be refined further by estimation of the residual ovarian reserve. Increasing data derived from spontaneous and gonadotoxic-induced POI cohorts demonstrate the utility of anti-Müllerian hormone (AMH) to predict POI. This review presents current understanding of how genetics in combination with AMH may facilitate the prediction of POI.

Anti-Müllerian Hormone in the Diagnosis and Prediction of Premature Ovarian Insufficiency

The menopause and its pathological version, premature ovarian insufficiency (POI), are characterized by the cessation of follicle growth in the ovary, with consequent lack of estrogen production and amenorrhea. The measurement of a specific product of ovarian follicles would therefore be expected to be a valuable biomarker in women with POI, and to be of likely clinical value in the diagnosis and perhaps prediction of POI. Anti-Müllerian hormone (AMH) is produced by the granulosa cells of growing follicles and is therefore likely to be of value in this context. Current data indicate that measurement of AMH is an accurate indicator of POI in many situations and has diagnostic validity and may facilitate more timely diagnosis. AMH seems to be of limited value in predicting age at natural menopause, even with multiple measurements, and there are scarce data regarding prediction of POI, other than when it is imminent, and in some contexts where there is an immediate iatrogenic threat to ovarian function. AMH therefore appears to have considerable value as a diagnostic test for POI, but apart from highlighting broadly those at increased risk, it has inadequate precision to be able to predict accurately the timing of onset of impending POI.

Does the Anti-Mullerian Hormone Decline Rate Improve the Prediction of Age at Menopause?

OBJECTIVES

There are controversial studies investigating whether multiple anti-Mullerian hormone (AMH) measurements can improve the individualized prediction of age at menopause in the general population. This study aimed to reexplore the additive role of the AMH decline rate in single AMH measurement for improving the prediction of age at physiological menopause, based on two common statistical models for analysis of time-to-event data, including time-dependent Cox regression and Cox proportional-hazards regression models.

METHODS

A total of 901 eligible women, aged 18-50 years, were recruited from the Tehran Lipid and Glucose Study (TLGS) population and followed up every 3 years for 18 years. The serum AMH level was measured at the time of recruitment and twice after recruitment within 6-year intervals using the Gen II AMH assay. The added value of repeated AMH measurements for the prediction of age at menopause was explored using two different statistical approaches. In the first approach, a time-dependent Cox model was plotted, with all three AMH measurements as time-varying predictors and the baseline age and logarithm of annual AMH decline as time-invariant predictors. In the second approach, a Cox proportional-hazards model was fitted to the baseline data, and improvement of the complex model, which included repeated AMH measurements and the logarithm of the AMH annual decline rate, was assessed using the C-statistic.

RESULTS

The time-dependent Cox model showed that each unit increase in the AMH level could reduce the risk of menopause by 87%. The Cox proportional-hazards model also improved the prediction of age at menopause by 3%, according to the C-statistic. The subgroup analysis for the prediction of early menopause revealed that the risk of early menopause increased by 10.8 with each unit increase in the AMH annual decline rate.

CONCLUSION

This study confirmed that multiple AMH measurements could improve the individual predictions of the risk of at physiological menopause compared to single AMH measurements. Different alternative statistical approaches can also offer the same interpretations if the essential assumptions are met.

Role of AMH in Prediction of Menopause

Anti-Müllerian Hormone (AMH) is produced by small antral follicles and has evolved over the past three decades as an assumed potential marker of the number of follicles in the human ovaries, also known as ovarian reserve. This quantitative measure, given the gradual decline over time and its non-replenishable feature, could be the dreamed marker for predicting the final exhaustion of ovarian storage: the post-menopause. This introductory chapter summarizes current knowledge with regard to the contribution of serum AMH measurements to predict age of normal menopause and critically discuss its potential in this regard. Furthermore, its predictive role in the context of menopause in association with several frequently occurring fertility disorders such as premature menopause, polycystic ovarian syndrome and endometriosis are discussed. Overall, while ovarian reserve markers including AMH are unmistakably related to age at menopause, they are insufficiently precise to inform on an individual's journey of ovarian aging.

Anti-Müllerian Hormone and Ovarian Reserve: Update on Assessing Ovarian Function

CONTEXT

Anti-müllerian hormone (AMH) is produced by granulosa cells of small, growing follicles in the ovary. Serum AMH levels strongly correlate with the number of growing follicles, and therefore AMH has received increasing attention as a marker for ovarian reserve. This review summarizes recent findings and limitations in the application of serum AMH in ovarian reserve assessment.

EVIDENCE ACQUISITION

A PubMed search was conducted to find recent literature on the measurements and use of serum AMH as a marker for ovarian reserve.

EVIDENCE SYNTHESIS

Serum AMH levels are measured to assess the "functional ovarian reserve," a term that is preferred over "ovarian reserve," since AMH levels reflect the pool of growing follicles that potentially can ovulate. Serum AMH levels are used in individualized follicle-stimulating hormone dosing protocols and may predict the risk of poor response or ovarian hyperstimulation syndrome but has limited value in predicting ongoing pregnancy. Serum AMH levels are studied to predict natural or disease-related age of menopause. Studies show that the age-dependent decline rates of AMH vary among women. The generalized implementation of serum AMH measurement has also led to an increase in diagnostic assays, including automated assays. However, direct comparison of results remains problematic.

CONCLUSION

Serum AMH remains the preferred ovarian reserve marker. However, the lack of an international standard for AMH limits comparison between AMH assays. Furthermore, little is known about endogenous and exogenous factors that influence serum AMH levels, which limits proper interpretation of AMH values in a clinical setting.

Impact of lignans in oilseed mix on gut microbiome composition and enterolignan production in younger healthy and premenopausal women: an in vitro pilot study

BACKGROUND

Dietary lignans belong to the group of phytoestrogens together with coumestans, stilbenes and isoflavones, and themselves do not exhibit oestrogen-like properties. Nonetheless, the gut microbiota converts them into enterolignans, which show chemical similarity to the human oestrogen molecule. One of the richest dietary sources of lignans are oilseeds, including flaxseed. The aim of this pilot study was to determine the concentration of the main dietary lignans in an oilseed mix, and explore the gut microbiota-dependent production of enterolignans for oestrogen substitution in young and premenopausal women. The oilseed mix was fermented in a pH-controlled batch culture system inoculated with women's faecal samples. The lignan content and enterolignan production were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), and the faecal-derived microbial communities were profiled by 16S rRNA gene-based next-generation sequencing.

RESULTS

In vitro batch culture fermentation of faecal samples inoculated with oilseed mix for 24 h resulted in a substantial increase in enterolactone production in younger women and an increase in enterodiol in the premenopausal group. As for the gut microbiota, different baseline profiles were observed as well as different temporal dynamics, mainly related to Clostridiaceae, and Klebsiella and Collinsella spp.

CONCLUSIONS

Despite the small sample size, our pilot study revealed that lignan-rich oilseeds could strongly influence the faecal microbiota of both younger and premenopausal females, leading to a different enterolignan profile being produced. Further studies in larger cohorts are needed to evaluate the long-term effects of lignan-rich diets on the gut microbiota and find out how enterolactone-producing bacterial species could be increased. Diets rich in lignans could potentially serve as a safe supplement of oestrogen analogues to meet the cellular needs of endogenous oestrogen and deliver numerous health benefits, provided that the premenopausal woman microbiota is capable of converting dietary precursors into enterolignans.