Efficacy of predictive models for polycystic ovary syndrome using serum levels of two antimüllerian hormone isoforms (proAMH and AMHN,C)

Proteolytic activation of anti-Müllerian hormone is suppressed in adolescent girls

PURPOSE

The ratio of the anti-Müllerian hormone (AMH) precursor (proAMH) to active AMH (AMH_N,C) is higher in childhood than in adulthood but has never been quantified during adolescence. The ratio of proAMH to total AMH (AMH prohormone index, API) was examined during the puberty in healthy girls. The API was also compared between girls with and without polycystic ovary syndrome (PCOS) to determine if there were differences that could assist in PCOS diagnosis during adolescence.

METHODS

Total AMH and proAMH were measured by immunoassay in a single-centre, cross-sectional observational study; 61 controls and 29 girls with PCOS were included in the study (age range 8-21 years). The API was calculated as proAMH as a percentage of total AMH. Differences in API between control and PCOS subjects and across age-groups were examined by Welch's ANOVA. The relationship between API and a range of metabolic parameters was examined by Pearson correlation.

RESULTS

The API in healthy females increased between the ages of 10~15 years and declined from 15~20 years (p < 0.001). The API was negatively correlated with body mass index in the control (p = 0.04) and PCOS groups (p = 0.007). The API was associated with factors related to adiposity and lipid metabolism. The API was not significantly different in control girls and girls with PCOS.

CONCLUSIONS

Higher API during adolescence suggests that proteolytic activation of proAMH is suppressed during this life stage. API was not different between control girls and girls with PCOS indicating that it is not useful in diagnosis of PCOS during adolescence.

Molecular Mechanisms of AMH Signaling

Anti-Müllerian Hormone (AMH) is a secreted glycoprotein hormone with critical roles in reproductive development and regulation. Its chemical and mechanistic similarities to members of the Transforming Growth Factor β (TGF-β) family have led to its placement within this signaling family. As a member of the TGF-β family, AMH exists as a noncovalent complex of a large N-terminal prodomain and smaller C-terminal mature signaling domain. To produce a signal, the mature domain will bind to the extracellular domains of two type I and two type II receptors which results in an intracellular SMAD signal. Interestingly, as will be discussed in this review, AMH possesses several unique characteristics which set it apart from other ligands within the TGF-β family. In particular, AMH has a dedicated type II receptor, Anti-Müllerian Hormone Receptor Type II (AMHR2), making this interaction intriguing mechanistically as well as therapeutically. Further, the prodomain of AMH has remained largely uncharacterized, despite being the largest prodomain within the family. Recent advancements in the field have provided valuable insight into the molecular mechanisms of AMH signaling, however there are still many areas of AMH signaling not understood. Herein, we will discuss what is known about the biochemistry of AMH and AMHR2, focusing on recent advances in understanding the unique characteristics of AMH signaling and the molecular mechanisms of receptor engagement.

Anti-Müllerian Hormone in Female Reproduction

Anti-Müllerian hormone (AMH), also called Müllerian inhibiting substance, was shown to be synthesized by the ovary in the 1980s. This article reviews the main findings of the past 20 years on the regulation of the expression of AMH and its specific receptor AMHR2 by granulosa cells, the mechanism of action of AMH, the different roles it plays in the reproductive organs, its clinical utility, and its involvement in the principal pathological conditions affecting women. The findings in respect of regulation tell us that AMH and AMHR2 expression is mainly regulated by bone morphogenetic proteins, gonadotropins, and estrogens. It has now been established that AMH regulates the different steps of folliculogenesis and that it has neuroendocrine effects. On the other hand, the importance of serum AMH as a reliable marker of ovarian reserve and as a useful tool in the prediction of the polycystic ovary syndrome (PCOS) and primary ovarian failure has also been acknowledged. Last but not least, a large body of evidence points to the involvement of AMH in the pathogenesis of PCOS.

Establishment of a homogeneous immunoassay-light-initiated chemiluminescence assay for detecting anti-Müllerian hormone in human serum

Anti-Müllerian hormone (AMH) is known as a reliable marker of ovarian reserve (OR). The determination of AMH is of great importance and most existed AMH detection methods are heterogeneous immunoassay. In this study, a novel homogeneous sandwich immunoassay-light-initiated chemiluminescence assay (LICA) for detecting AMH serum level was developed. This AMH-LICA was performed by incubating serum samples with AMH mouse monoclonal antibody coated with chemibeads, streptavidin-coated sensibeads, and biotinylated AMH mouse monoclonal antibody. Sensitivity, precision, accuracy and cross-reactivity of this assay were evaluated. Besides, a regression analysis showed a high correlation between AMH-LICA and Roche Elecsys® AMH assay (y = 0.9851x + 0.07147, R² = 0.9569). As a homogeneous immunoassay, this AMH-LICA could accurately and rapidly determine the serum level of AMH with high-throughput. Thus, this new developed assay may be a new useful analytical tool for the determination of AMH.

Human Chorionic Gonadotrophin (hCG) Trigger-Mediated Ovulation Induction in Infertility Management in South Indian Women Undergoing IVF/ICSI Regimens: A Pilot Sexual Medicine Study with Public Health Perspective

Introduction:

Infertility is a global public health problem; cost-effective patient-friendly treatment modalities along with psychosexual intervention strategies are essential for infertility control/prevention/management among ethnically disparate populations.

Objectives:

This study aimed to assess differential in vitro fertilization (IVF) success trends among infertile women of South Indian ethnicity.

Materials and Methods:

Prospective, observational study designed in a hospital-based setting with active enrollment of infertile women undergoing IVF/intracytoplasmic sperm injection (ICSI) at Indira IVF Center, Chennai, Tamil Nadu, India (April-September 2019); inclusion criteria: age >35 years, South Indian ethnicity, married >1 year, absence of full-term clinical pregnancy, endometrial thickness <6 mm/thin endometrium; exclusion criteria: prior ≥2 IVF failures, fibroids/adenomyosis/cervical cancer/endometriosis. IVF success was determined by evaluating total frozen embryos transferred/month, average oocyte yield/donor, oocyte quality, M-II oocytes, biochemical/clinical pregnancy (beta-human chorionic gonadotropin positivity/fetal cardiac activity). Mycobacterium tuberculosis positivity was assessed by GeneXpert polymerase chain reaction-based technology, and psychosexual intervention-incorporated marital relationship counseling sessions/therapy, referrals for psychiatric assessments (cognitive impairment/schizophrenia/depression). Written informed consent of participants was taken and study was approved by Institutional Review Board.

Results:

Mean age and endometrial thickness of study participants were 33.3 years (SD ±1.9) and 8.7 mm (SD ±0.5), respectively; average Body Mass Index (BMI) and anti-müllerian hormone (AMH) levels were 28.4 kg/m2 and 4.7 ng/mL, respectively. Embryos transferred/month: 7 in April/13 in May/24 in June/36 in July/24 in August/30 in September, and pregnancies: 4/8/17/26/20/22 for the months of April, May, June, July, August, and September 2019, respectively. Subgroup stratification demonstrated M-II vs total oocytes retrieved were 76%, 73%, 60%, 71%, 77%, and 77%. Overall IVF success rates were 57% in April/62% in May/71% in June/72% in July/83% in August/73% in September; frozen embryo transfer success was 0 in April-May/67% in June/73% in July/89% in August/100% in September 2019. English/Tamil-speaking infertile women self-reported treatment-related satisfaction rates of 80% to 100%.

Conclusion:

M-II oocytes’ yield, sociodemographics of infertile women, and increasing age/aberrant AMH/BMI profiles/endometrial receptivity/diminished ovarian reserve are promising predictors of IVF/ICSI success in genetically distinct patient population subset(s). Future multicentric gene epidemiology studies with larger sample size and precision-based psychiatric assessments/interventions are warranted for development of predictive biomarkers in infertility management.

Large ovarian endometriomas are associated with high pre-operative anti-Müllerian hormone concentrations

RESEARCH QUESTION

Are large ovarian endometriomas associated with high pre-operative anti-Müllerian hormone (AMH) concentrations?

DESIGN

Data from 332 women who underwent AMH measurement before surgery for endometriosis were prospectively recorded in a large database. Univariate analysis compared AMH concentrations in terms of the patients' baseline characteristics. A multivariate model was used to identify variables having an independent relationship with AMH concentration.

RESULTS

Among 332 women included in the study, 47.6% were aged 18-30 years, 67.8% were infertile and 85.5% were nulliparous. A total of 66.3% had ovarian endometriomas, and 10.8% had cysts measuring over 6 cm. Bilateral cysts over 3 cm were recorded in 24.7% of the women. Univariate analysis identified two variables that had a statistically significant relationship with AMH concentration: the woman's age (P = 0.01) and cyst size (P < 0.001). Multivariate analysis revealed that ages of 36-40 years and over 40 years showed a significant association with lower AMH concentrations (P = 0.02 and P = 0.009, respectively), while a cyst size of over 6 cm was statistically associated with high AMH concentrations (P < 0.001), after adjustment for smoking, parity, rectosigmoid endometriotic nodules and a bilateral location of endometriomas.

CONCLUSIONS

Pre-operative AMH concentration was significantly increased in women with large endometriomas of over 6 cm, independent of their age or the presence of bilateral endometriomas. This is relevant for both surgeons and patients when planning surgery in women with an intention to conceive post-operatively.

The proportion of cleaved anti-Müllerian hormone is higher in serum but not follicular fluid of obese women independently of polycystic ovary syndrome

RESEARCH QUESTION

Does the relative distribution of anti-Müllerian hormone (AMH) isoforms differ between patients depending on their body mass index (BMI) and polycystic ovary syndrome (PCOS) status in serum and follicular fluid?

DESIGN

Obese and normal weight patients (PCOS [n = 70]; non-PCOS [n = 37]) were selected for this case-control study in the serum. Between 2018 and 2019, obese (n = 19) and normal weight (n = 20) women with or without PCOS who were receiving IVF treatment were included in the follicular fluid study. The bio-banked serums and follicular fluid were tested for total AMH (proAMH and AMH_N,C combined) and proAMH using an automatic analyzer. The AMH prohormone index (API = [proAMH]/[total AMH]x 100) was calculated as an inverse marker of conversion of proAMH to AMH_N,C, with only the latter isoform that could bind to the AMH receptor complex.

RESULTS

The API was not significantly different between controls and women with PCOS, whereas obese women had a lower API compared with their normal weight counterparts. Grouping PCOS and controls, a lower API was found in obese versus normal weight women, suggesting a greater conversion of proAMH to AMH_N,C. The API in the serum was significantly correlated with metabolic parameters. In the follicular fluid, API is not different between obese and normal weight women independently of PCOS and is higher than in the concomitant serum.

CONCLUSIONS

The proportion of inactive form of AMH in the serum is higher in normal weight versus obese women but not in the follicular fluid, independently of PCOS. The conversion of proAMH into the cleaved isoform is likely to occur in extra-ovarian tissues and to exacerbate in obese individuals.

Anti-müllerian hormone in the pathophysiology and diagnosis of polycystic ovarian syndrome

PURPOSE OF REVIEW

Polycystic ovarian syndrome (PCOS) is the most common cause of chronic anovulation and hyperandrogenism in young women and represents a true public health concern and an economic burden.

RECENT FINDINGS

The pathophysiology of PCOS is still not fully understood, but progresses have been made and the relationships between anti mullerian hormone (AMH), follicle stimulating hormone, luteinizing hormone, E2 and androgens have been explored. The follicle excess plays a central role in the syndrome and AMH is definitively a major component of this phenomena.

SUMMARY

The aim of this chapter is to present the recent work studying the role of AMH in the pathophysiology of PCOS and to discuss the improvement that serum AMH assay brings in the diagnosis of PCOS.