Circulating Anti-Müllerian Hormone Concentrations Research Articles

Anti-Müllerian hormone in female dromedary camel and its association with super-ovulatory response in embryo donors

Anti-Müllerian hormone (AMH) has a conserved role in regulating the reproductive cycle in several species. Its circulating concentration reflects the size of the growing primordial follicle reserve and is a reliable predictor of superovulation response in embryo/oocyte donors. This study investigated the possible application of AMH measurement in dromedary camels (Camelus dromedarius) multiple ovulation embryo transfer programs. In experiment 1, the follicular cycle of synchronized and naturally cycling camels (n = 12) was monitored. Blood was collected at 6 timepoints in 2 consecutive cycles corresponding to emergence, mid-cycle, and dominance in both group and hormonal fluctuations were evaluated for repeatability of measurements within and between cycles. In experiment 2, the correlation between circulating AMH concentrations prior to initiation of superovulation and the outcome of superovulation was evaluated. The results were compared between donors with higher (n = 7) and lower than median (n = 8) AMH values. Mean AMH concentrations in synchronized and non-synchronized camels were 1.46 ± 0.15 and 0.95 ± 0.09, respectively. Intercycle and intracycle values of AMH showed high repeatability in camels of both groups (>96.4% and >92.74%, respectively) with significant correlations between values at different stages of the ovarian cycle (Emergence and mid-cycle: R2 = 0.82; emergence and. dominance: R2 = 0.86; Mid-cycle and dominance: R2 = 0.93, P < 0.05). Total follicles, CLs, and recovered embryos were highly correlated with AMH values prior to superovulation (R2 = 0.64, R2 = 0.77, and R2 = 0.64, respectively, P < 0.05). A greater number of developed follicles prior to mating (17.00 ± 2.09 vs. 7.62 ± 1.06), CLs (12.58 ± 1.36 vs. 5.12 ± 0.93), transferable (10.85 ± 1,31 vs. 3.37 ± 0.82), and spherical embryos (8.14 ± 1.07 vs. 2.62 ± 0.7) were observed in camels with higher than median concentrations of AMH (P < 0.05). Fluctuations in estradiol and progesterone did not affect variations in mean AMH values (r2 < 0.19 and r2 < 0.24, respectively, P > 0.05). In conclusion, highly consistent AMH values in dromedary camels are a reliable predictor of superovulation response and outcome in dromedary camels.

Serum Anti-Müllerian Hormone Levels and Estrous Monitoring of GnRH Agonist Deslorelin-Induced Estrus in Bitches: A Pilot Study.

This study was performed to monitor estrous patterns and, more importantly, changes in anti-Müllerian hormone (AMH) concentrations during the peri-ovulatory period in deslorelin-induced estrous bitches. Healthy anestrous bitches (n = 4) were used. Estrus and ovulation were monitored after deslorelin implantation. Blood samples were collected for analysis of progesterone, estradiol-17ß and AMH concentrations before implantation (day 0) and on days 6, 8, 10, 12, 14, 16, 18, 20 and 22 after implantation. Six days following treatment, all bitches showed estrus signs. Ovulation took place between days 12 and 15. Circulating AMH concentrations varied among bitches from 0.12 to 3.08 ng/mL. However, no significant differences in AMH levels (mean ± SD) were observed between day 0 and days following post-implantation (p &gt; 0.05). There were no significant correlations between AMH and estradiol or AMH and progesterone (p &gt; 0.05). Ultrasonographically, the number of clearly identifiable ovarian follicles was higher before ovulation and the area of ovaries increased after ovulation (p &lt; 0.05). Except for AMH, changes in vaginal cytology, estradiol-17ß and progesterone levels observed in our study were similar to naturally occurring estrus. Large intra- and inter-individual variation in AMH were observed suggesting that AMH is currently not suitable as a canine fertility marker to monitor ovarian response to deslorelin treatment for estrus induction.

Characterizing Anti-Müllerian Hormone (AMH) concentration and change over time in Holstein dairy cattle

The objective of this study was to characterize circulating Anti-Müllerian Hormone (AMH) concentrations in a population of Holstein heifers and examine the impact that life events and stage of life have on those concentrations. Virgin, Holstein heifers (n = 105) 13 ± 0.8 months old were heat detected using tail-chalk, bred via artificial insemination and pregnancy checked 32+ days later. Serum samples for AMH were collected upon enrollment (heifer), at 5–20 days in milk (fresh) and at 45–60 days in milk (pre-breeding). Transrectal ultrasonography was performed upon enrollment (heifer) and at 45–60 days in milk (pre-breeding) to determine antral follicle count (AFC), cyclicity status, and uterine health. Heifers were blocked into thirds by AMH concentration: HIGH (>354 pg/mL; n = 34), MID (183–354 pg/mL; n = 35) and LOW (<183 pg/mL; n = 36), with distribution re-evaluated at subsequent samplings (fresh, pre-breeding). As heifers, age and conception risk to first service were not impacted by AMH (P > 0.05). Reason for leaving the herd, health incidences and calving difficulty were not impacted by AMH (P > 0.05). AFC and cyclicity had a positive impact on heifer AMH (P < 0.01). AFC and AMH in heifers were highly correlated (0.56, P < 0.001). AFC for heifers differed by AMH group with the HIGH group having the greatest AFC (8.76), followed by the MID (5.87), then the LOW (3.53) group (P < 0.0001). However, this association was not evident in the pre-breeding group (P > 0.05). From the heifer to the fresh sample, average AMH dropped from 313.15 pg/mL to 160.01 pg/mL (P < 0.0001). Average AMH at the pre-breeding sample was 183.23 pg/mL, which was lower than the heifer sample (P < 0.0001), but not different from the fresh sample (P > 0.05). AFC and AMH at the heifer sample had a positive impact on AMH at the fresh sample (P < 0.01) and pre-breeding AMH was positively impacted by both the fresh and heifer AMH concentration (P < 0.001). Most animals kept their AMH categorization through all three time points with more of the LOW AMH animals maintaining their categorization than the other groups. However, 32.1% of animals changed their AMH categorization from the heifer sample to the fresh sample, with 53.8% moving to a lower AMH categorization (corresponding to lower AMH) and 46.2% moving to a higher AMH categorization (corresponding to higher AMH). No differences were seen in circulating AMH based on health events however, differences in AMH concentration over time indicate a drop in circulating AMH post-calving. Circulating AMH concentration as a pre-breeding heifer is highly indicative of circulating AMH concentration as a first lactation animal and may be used to predict an adult animal’s AMH concentration. However, it is necessary to compare AMH concentrations to herdmates as published AMH values vary widely from herd to herd. In addition, sampling time should be considered when determining AMH categorization of animals as circulating AMH concentration immediately post-calving may not be indicative of an animal’s true AMH categorization.

Do BRCA1 and BRCA2 gene mutation carriers have a reduced ovarian reserve? Protocol for a prospective observational study

IntroductionBRCA1/2 gene mutations increase risk of breast and/or ovarian cancer and may have implications for reproductive health. Indirect biomarkers of the ovarian primordial follicle pool (anti-Müllerian hormone (AMH)) and one...

Physiology and endocrinology symposium: Anti-Müllerian hormone: a biomarker for the ovarian reserve, ovarian function, and fertility in dairy cows.

This review summarizes studies we conducted to test the hypothesis that size of the ovarian reserve (number of healthy follicles and oocytes in ovaries) positively impacts ovarian function and fertility in cattle. Key results, primarily in Bos taurus dairy cattle, show that antral follicle count (AFC) during follicular waves is highly variable between individuals, but very highly repeatable within individuals. Cycling heifers with low (≤15 follicles ≥3 mm, ~20% of a herd) vs. a high AFC (≥25, ~20% of a herd) have a smaller ovarian reserve, higher FSH but lower anti-Müllerian hormone (AMH), androstenedione, estradiol, and progesterone concentrations. Moreover, cattle with low AFC have a thinner endometrium, decreased response of granulosal, thecal, or luteal cells to FSH or LH and a poorer response to superovulation compared to cattle with high AFC. Interestingly, cows with a very high AFC as heifers have reduced fertility, fewer lactations, and shorter herd longevity, whereas cows with a low vs. intermediate AFC have reduced fertility, fewer lactations, and shorter herd longevity. Anti-Müllerian hormone concentrations are static within individuals but highly positively correlated with AFC, but fertility is not correlated with circulating AMH concentration in heifers and dairy cows with low vs. a higher AMH as heifers have reduced fertility and a shorter herd longevity. Anti-Müllerian hormone concentrations in dairy heifers are a moderately heritable trait (36%), and negatively impacted by inadequate maternal nutrition during early pregnancy or high maternal somatic cell count. We conclude that genetic or environmental manipulations of AMH could enhance size of the ovarian reserve and ovarian function, thereby improving fertility, response to superovulation, and longevity in dairy cows.

125 Anti-Müllerian Hormone (AMH): a biomarker for the ovarian reserve, ovarian function and fertility in dairy cows.

This presentation summarizes studies we conducted to test the hypothesis that size of the ovarian reserve (number of healthy follicles and oocytes in ovaries) positively impacts ovarian function and fertility in cattle. Key results primarily in dairy cattle show: 1) Antral follicle count (AFC) during follicular waves is highly variable between individuals but very highly repeatable within individuals. 2) Cycling heifers with low (≤ 15 follicles ≥3 mm, ~20% of a herd) vs a high (≥25 AFC, ~20% of a herd) have: i) a smaller ovarian reserve; ii) higher FSH but lower AMH, androstenedione, estradiol and progesterone concentrations and a thinner endometrium; iii) decreased response of granulosal, thecal or luteal cells to FSH or LH; and iv) a poorer response to superovulation. 3) Cows with a very high AFC as heifers have reduced fertility, fewer lactations and shorter herd longevity. 4) Cows with a low vs intermediate AFC have reduced fertility, fewer lactations and shorter herd longevity. 5) AMH concentrations are static within individuals but highly positively correlated with AFC. 6) A single AMH measurement is highly positive correlated with the average of multiple AMH measurements on different days of the cycle and AFC. 7) Fertility is not correlated with circulating AMH concentration in heifers. 8) Dairy cows with low vs a higher AMH as heifers have reduced fertility and a shorter herd longevity. 9) AMH concentrations in dairy heifers is a moderately heritable trait (36%), and negatively impacted by inadequate maternal nutrition during early pregnancy or high maternal somatic cell count. We conclude that genetic or environmental manipulations of AMH could enhance size of the ovarian reserve and ovarian function, thereby improving fertility, response to superovulation and longevity in dairy cows. Research support: NRI Grants no. 2004-35203-14781 and 2007-35203-18178; AFRI Grants 2013-67015-20962; MSU’s AgBioResearch; and Green Meadow Farms, Inc.

Dietary factors and serum antimüllerian hormone concentrations in late premenopausal women

To study the associations between dietary factors and circulating antimüllerian hormone (AMH) concentrations among late premenopausal women. AMH concentrations were measured in serum samples collected at enrollment from 296 women (aged 35-45years) in the Sister Study cohort. Usual dietary intakes in the past 12months were assessed using a validated food frequency questionnaire. Dietary exposures of interest included macronutrients, dietary fat subtypes, fiber, and glycemic index. Multivariable linear regression was used to evaluate associations between dietary variables and serum AMH concentrations. We also used nutrient density models to examine isocaloric replacement of macronutrients. Not applicable. Women aged 35-45years. Not applicable. Serum AMH concentrations in nanograms per milliliter (ng/mL). AMH concentrations were positively associated with percentage of energy from carbohydrates (β per 5% calories = 0.141 [95% CI 0.023, 0.259]; P trend = .019), and inversely associated with percentage of energy from fat (β per 5% calories = -0.152 [95% CI -0.299, -0.004]; P trend = .044). In analyses of dietary fat subtypes, AMH decreased with increasing monounsaturated fatty acids (P trend = .082) and polyunsaturated fatty acids (P trend = .043), particularly ω-6 fatty acids (P trend = .044), whereas no strong trend was observed for saturated fatty acids. Protein and alcohol intake were not strongly associated with AMH. Our cross-sectional analyses in a sample of late premenopausal women suggest that dietary fat intake may be inversely associated with circulating AMH concentrations. Further research in prospective studies is warranted to evaluate dietary factors as potential modifiers of ovarian reserve.

The utility of anti-Müllerian hormone in women with chronic kidney disease, on haemodialysis and after kidney transplantation

Women with renal disease have menstrual and gonadal dysfunction manifesting as hormonal imbalance. Anti-Müllerian hormone (AMH) is a potential measure of ovarian reserve. We examined circulating AMH concentrations in young women with renal failure, determined associations with clinical characteristics, and compared AMH with age-matched healthy individuals. AMH was measured in 77 women: 26 had chronic kidney disease (CKD), 26 were on haemodialysis (HD), and 25 had a kidney transplant. Random AMH levels were highest in women on HD [HD 2.9 (1.1-5.2), CKD 1.6 (0.7-2.2), transplant 1.5 (1.0-4.2) ng/ml]. On multiple linear regression, AMH was 53% higher [95% CI 0.20-0.98, P = 0.002] in women on HD and decreased by 20% per 5-year increase in age (P < 0.001). AMH was 43% lower in women with renal failure compared with 600 age-matched controls [1.7 (0.9-3.8) versus 3.0 (1.9-5.0) ng/ml, P < 0.001]; however, we found no difference in AMH between those on HD and healthy individuals [2.9 (1.1-5.2) versus 3.0 (1.9-5.0) ng/ml]. AMH may be a useful biomarker in female renal patients with non-dialysis dependent renal disease pursuing pregnancy. In contrast, AMH levels are higher in HD but unlikely to reflect ovarian reserve.

Anti-Müllerian Hormone (AMH) and fertility management in agricultural species

A reliable, easy to assess marker for fertility in agricultural species would be highly desirable and Anti-Müllerian Hormone (AMH) is a promising candidate. This review summarizes recent findings concerning AMH and its role in fertility management, mainly in cattle. It focuses on (1) alterations in circulating AMH concentrations from birth to puberty and during estrous cycles; (2) correlation of circulating AMH concentrations with ovarian follicle numbers and ovarian reserve; (3) factors that impact circulating AMH concentrations; (4) use of AMH as a predictor of fertility. Circulating AMH concentrations can be easily and reliably measured with a single blood sample in adult cattle because AMH varies minimally during the estrous cycle and is repeatable across multiple cycles. Circulating AMH concentrations are positively associated with several measures of fertility. Dairy heifers with low compared with higher AMH concentrations subsequently had lower pregnancy rates, higher probability of being culled after birth of their first calf and shorter herd longevity. Also, AMH is predictive of response to superovulation in cattle and sheep. Several factors contribute to the variability in AMH concentrations among individuals; for example, beef cattle have higher AMH than dairy cattle. Nutritional imbalances, disease and endocrine disruptors during fetal life may negatively program the size of the ovarian reserve and consequently serum AMH concentrations and potential fertility in adulthood. We conclude that AMH may be a predictor of fertility and herd longevity in cattle, whereas in sheep and other farm species, the potential association between AMH and reproductive performance remains largely unexplored.Free Italian abstract: An Italian translation of this abstract is freely available at http://www.reproduction-online.org/content/154/1/R1/suppl/DC1.

Molecular changes in the equine follicle in relation to variations in antral follicle count and anti-Müllerian hormone concentrations.

The wide variation in circulating anti-Müllerian hormone (AMH) concentrations between mares is attributed to differences in antral follicle count (AFC) which may reflect follicular function. There are few data regarding variations in AFC and associated regulatory factors for AMH in the equine follicle during follicular development. To examine molecular and hormonal differences in the equine follicle in relation to variations in AFC and circulating AMH concentrations during follicular development and to identify genes co-expressed with AMH in the equine follicle. Observational study. Plasma AMH concentrations and AFC were determined in 30 cyclic mares. Granulosa cells, theca cells and follicular fluid were recovered from growing (n = 17) or dominant follicles (n = 13). The expression of several genes, known to be involved in folliculogenesis and steroidogenesis, was examined using real-time reverse transcriptase polymerase chain reaction and immunohistochemistry. Intrafollicular oestradiol and AMH concentrations were determined by immunoassay. Within growing follicles, the expression of AMH, AMHR2, ESR2 and INHA in granulosa cells was positively correlated with AFC and plasma AMH concentrations. In addition, the expression of ESR1 and FSHR was positively associated with plasma AMH concentrations. No significant associations were detected in dominant follicles. Furthermore, there was no association between AMH or oestradiol concentrations in follicular fluid and variations in AFC. Finally, the expression of AMH and genes co-expressed with AMH (AMHR2, ESR2 and FSHR) in granulosa cells as well as intrafollicular AMH concentrations decreased during follicular development while intrafollicular oestradiol concentrations increased and were inversely related to intrafollicular AMH concentrations. This study indicates that variations in AFC and circulating AMH concentrations are associated with molecular changes in the growing equine follicle.

Relationship between circulating anti-Müllerian hormone (AMH) and superovulatory response of high-producing dairy cows

The main objective of this study was to evaluate the relationship between circulating anti-Müllerian hormone (AMH) and superovulatory response of dairy cows. Holstein cows (n=72) were milked twice daily and housed and fed individually in tiestalls. All animals were synchronized and flushed at 70±3 d in milk (DIM), near peak production (39.6kg/d). Blood samples for AMH analysis were collected at 3 different stages of a synchronized estrous cycle [at a random stage (40±3 DIM), proestrus (50±3 DIM), and diestrus (57±3 DIM)]. Body weights were measured weekly from calving until embryo collection. Statistical analyses were performed with Proc CORR and Proc GLIMMIX of SAS (SAS Institute Inc., Cary, NC). The 3 AMH samples from individual cows were correlated and not influenced by day of cycle. Surprisingly, AMH tended to be negatively correlated with body weight loss from calving to embryo collection (r=−0.22). More importantly, average AMH was highly associated (r=0.65) with superovulation response (number of corpora lutea on the day of the flush, CLN), total structures collected (r=0.48), and total transferable embryos (r=0.37), but not percentage of fertilized embryos (r=−0.20) or degenerate embryos (r=0.02). When cows were classified into quartiles (Q) of circulating AMH (Q1=0.01 to 82.6pg/mL; Q2=91.1 to 132.5pg/mL; Q3=135.3 to 183.8pg/mL; Q4=184.4 to 374.3pg/mL), we observed a >2-fold difference between first and fourth AMH quartiles in superovulation response (CLN: Q1=12.0±1.5; Q2=14.7±2.0; Q3=17.2±1.2; Q4=25.6±1.5) and embryo production. In conclusion, circulating AMH concentration was strongly associated with superovulation response, and evaluation of AMH could be used to identify cows with greater responses to superstimulation and thus improve efficiency of superovulation programs in dairy cows.

Association of antimüllerian hormone levels with menstrual-cycle type and dysmenorrhea in young asymptomatic women

To examine the association between antimüllerian hormone (AMH) levels and menstrual-cycle and lifestyle characteristics among young Japanese women. Cross-sectional study. University. Female students aged 20-22 years (n=65) who had never used oral contraceptives. Participants completed a questionnaire on reproductive and lifestyle characteristics, and kept a menstrual-cycle diary for 5 consecutive months. Serum AMH was measured once during the study period. Serum AMH concentration. Compared with women with very mild menstrual pain, serum AMH concentration was 49.6% (95% CI 6.5%-72.8%) lower among women with severe menstrual pain. Higher AMH concentration was associated with irregular menstrual cycles. Even after adjusting for menstrual-cycle regularity and its interaction, more-severe menstrual pain was associated with significantly lower AMH concentration. Circulating AMH concentration was significantly lower among young Japanese women who had more-severe menstrual pain. Underlying physiological mechanisms need to be addressed in future studies.

Serum anti-Müllerian hormone concentrations in stallions: Developmental changes, seasonal variation, and differences between intact stallions, cryptorchid stallions, and geldings

Anti-Müllerian hormone (AMH), a homodimeric glycoprotein, is secreted early in fetal life when it exerts a crucial function in sexual differentiation. The secretion of AMH in male humans persists after birth and is characterized by high prepubertal concentrations followed by a significant decrease at the onset of puberty. The expression of AMH in the normal and cryptorchid equine testis is well characterized but data regarding circulating AMH concentrations are lacking. The objectives of this study were to determine serum AMH concentrations in neonatal colts and fillies, prepubertal colts, and postpubertal stallions, and to evaluate variations in serum AMH related to season and gonadal status of stallions. In addition, we examined the presence and determined concentrations of AMH in seminal plasma of mature stallions. Serum AMH concentrations were significantly higher in neonatal colts than in neonatal fillies. Moreover, concentrations of AMH are high in prepubertal colts whereas significantly lower concentrations were detected after puberty. In intact mature stallions, season influenced AMH concentrations with significantly higher concentrations during spring and summer. Serum AMH concentrations were significantly higher in cryptorchid stallions compared with intact stallions or geldings. Finally, AMH was identified in seminal plasma of intact mature stallions, but there was no significant correlation between serum and seminal plasma AMH concentrations. In conclusion, serum AMH concentration varies with sex in the neonatal period, postnatal sexual development and season, and serum AMH concentration can be used as a biomarker for the presence of testicular tissue.

Which follicles make the most anti-Mullerian hormone in humans? Evidence for an abrupt decline in AMH production at the time of follicle selection

Anti-Müllerian hormone (AMH) is exclusively produced by granulosa cells (GC) of the developing pre-antral and antral follicles, and AMH is increasingly used to assess ovarian function. It is unclear which size follicles make the most AMH (total content) and are the main contributors to circulating AMH concentrations. To determine AMH gene expression in GC (q-RT-PCR) and follicular AMH production (Elisa and RIA) in relation to follicular development, 87 follicles (3-13 mm diameter) including both GC and the corresponding follicular fluid (FF) were collected in connection with fertility preservation of human ovaries. Further, follicle number and diameter, graded in 1 mm increments, were determined by 3D ultrasound in 113 women in their natural menstrual cycle to determine follicle number and diameter in relation to circulating AMH levels. This study demonstrates for the first time a positive association between AMH gene expression in human and both total follicular fluid AMH (P < 0.02) and follicular fluid AMH concentration (P < 0.01). AMH gene expression and total AMH protein increased until a follicular diameter of 8 mm, after which a sharp decline occurred. In vivo modelling confirmed that 5-8 mm follicles make the greatest contribution to serum AMH, estimated for the first time in human to be 60% of the circulating concentration. Significant positive associations between gene expression of AMH and FSHR, AR and AMHR2 expression (P < 0.00001 for all three) and significant negative association between follicular fluid AMH concentration and CYP19a1 expression were found (P < 0.0001). Both AMH gene expression (P < 0.02) and follicular fluid concentration of AMH (P < 0.00001) correlated negatively with estradiol concentration.

Anti-Müllerian hormone as a predictive endocrine marker for embryo production in the goat

Recently, we demonstrated the relationship between anti-Müllerian hormone (AMH) circulating concentrations, ovarian follicles, and embryo production in cattle. However, they have not yet been established in a species with a seasonal breeding activity. Thus, goats were subjected to repeated in vivo embryo production during the breeding season, at the end of the breeding season, and at the end of the anestrus season. Embryo production after FSH treatment was highly repeatable for each goat. Plasma AMH concentrations, measured before the first FSH treatment, were highly correlated with the number of collected, transferable, and freezable embryos, resulting from the three sessions of embryo production. Plasma AMH concentrations transiently decreased after each exogenous FSH treatment, but they showed little change with season, and no relationship was observed between AMH and endogenous FSH concentrations during seasonal transitions. Follicles of 1-5 mm in diameter were the main target of the FSH treatment and were major contributors to circulating AMH concentrations. Granulosa cell AMH expression decreased as the follicle approached terminal development, while the expression of maturation markers (CYP19A1 and FSHR) increased. In conclusion, circulating AMH concentrations can be predictive of the capacity of a donor goat to produce high or low numbers of high-quality embryos. This prediction could be accurately made from a single blood measurement of AMH during either breeding or anestrus seasons. Variability in the number of gonadotropin-responsive follicles of 1-5 mm in diameter between individuals resulted in the differences in circulating AMH concentrations measured between individuals.

Biological and clinical significance of anti-Müllerian hormone determination in blood serum of the mare

Anti-Müllerian hormone (AMH), a member of the transforming growth factor β superfamily of growth and differentiation factors, is expressed in granulosa cells of preantral and small antral ovarian follicles. In humans, AMH appeared to regulate recruitment and growth of small ovarian follicles. Furthermore, circulating AMH concentrations were elevated in women with granulosa-cell tumors (GCT). In the horse, GCTs are the most common tumor of the ovary, and a variety of endocrine assays have been used to diagnose presumptive GCTs. The objectives of the present study were to validate a heterologous enzyme immunoassay for determination of serum AMH in the horse, and to determine concentrations of AMH in the blood of mares during the estrous cycle, pregnancy, and in mares with granulosa-cell tumors. Mares with normal estrous cycles (n = 6) and pregnant mares (n = 6) had blood samples collected throughout one interovulatory period and monthly throughout gestation, respectively. Mares diagnosed with GCT had blood samples taken before (n = 11) and after ovariectomy (n = 5). Tumors were sectioned and fixed for immunohistochemistry and snap frozen for immunoblot analyses and RT-qPCR. In normal cyclic mares and in pregnant mares, there was no effect of cycle stage or month of gestation on serum AMH concentrations. In GCT mares, serum concentrations of AMH (1901.4 ± 1144.6 ng/mL) were higher than those in cyclic (0.96 ± 0.08 ng/mL) or pregnant (0.72 ± 0.05 ng/mL) mares and decreased after tumor removal. Both AMH and AMH receptor (AMHR2) immunolabeling and expression were detected by immunohistochemistry in the tumor and cyst fluid obtained from mares with GCTs. Therefore, we concluded that AMH was a useful biomarker for detection of granulosa-cell tumors in mares.

Serum concentrations of Anti‐Müllerian Hormone (AMH) in 95 patients with Klinefelter syndrome with or without cryptorchidism

Anti-Müllerian hormone (AMH) is produced by foetal Sertoli cells at the time of sexual differentiation and is responsible for the regression of the Müllerian ducts in the male foetus. AMH is a testis-specific marker of diagnostic value in infants with ambiguous genitalia or with bilateral cryptorchidism. However, little is known about AMH in boys and adult men with normal or abnormal gonadal function. We therefore aimed at determining circulating AMH concentrations in patients with 47,XXY Klinefelter syndrome (KS) with or without cryptorchidism. AMH was determined in 95 47,XXY patients aged 0.2-64.5 years, of which 12 patients had a history of cryptorchidism. AMH was within the normal range in boys with Klinefelter syndrome until puberty. The pubertal decline was delayed, especially in patients with a history of cryptorchidism. AMH was below -2 SD in 85% of adult KS. AMH secretion in patients with 47,XXY KS was within normal limits during mini-puberty and until puberty. Thereafter, AMH declined to subnormal levels in all patients. We hypothesize that this decline was a result of the hyalinization of seminiferous tubules in relation to puberty, rather than caused by disrupted regulatory mechanisms at the level of the pituitary-gonadal axis.

Influence of age and gender on secretion of anti-Müllerian hormone in Asian ( Elephas maximus) and African ( Loxodonta africana) elephants

Anti-Müllerian hormone (AMH) secretion was studied in Asian and African elephants varying in age and reproductive status. Overall mean concentrations did not differ (P > 0.05) between species, but were markedly higher in male than female Asian elephants (31.01 ± 4.22 ng/mL and 0.19 ± 0.02 ng/mL, mean ± SEM) and African elephants (40.27 ± 3.18 ng/mL, 0.17 ± 0.04 ng/mL), respectively. Anti-Müllerian hormone secretion was not significantly affected by ovarian cyclicity status (cycling vs noncycling), but was higher (P < 0.05) in prepubertal (0.40 ± 0.10 ng/mL) than reproductive age (8–35 y; 0.18 ± 0.04 ng/mL) and aged (≥ 36 y; 0.16 ± 0.03 ng/mL) females. In males, AMH secretion was not significantly affected by musth status, but was age-related, with higher concentrations (P > 0.05) in prepubertal (49.08 ± 6.11 ng/mL) as compared to aged (≥36 y; 22.27 ± 5.82 ng/mL) bulls; concentrations in mature bulls (8–35 y; 37.01 ± 3.17 ng/mL) were similar to prepubertal and older bulls. We concluded that circulating AMH concentrations in elephants were similar between species and not affected by reproductive status; however, concentrations were significantly higher in males than females, and in younger animals. The diagnostic value of AMH to assess fertility status of individual elephants remains to be determined.

Does size matter in females? An overview of the impact of the high variation in the ovarian reserve on ovarian function and fertility, utility of anti-Müllerian hormone as a diagnostic marker for fertility and causes of variation in the ovarian reserve in cattle

The mechanism whereby the inherently high variation in ovary size and the total number of high-quality oocytes in ovaries (ovarian reserve) impact on ovarian function and fertility, diagnostics to measure the size of the ovarian reserve and the factors that cause variation in the ovarian reserve are unknown. Our results show that cattle can be phenotyped reliably based on the number of antral follicles growing during follicular waves (antral follicle count, AFC). Young adult cattle with a consistently low v. a high AFC have smaller gonads, a markedly diminished ovarian reserve and many other phenotypic characteristics usually associated with ovarian aging and infertility. A powerful new approach based on a single measurement of serum concentration of anti-Müllerian hormone (AMH) is described to test the longstanding hypothesis that the size of the ovarian reserve is positively associated with fertility. Also, new evidence shows that maternal environment has a critical role in regulation of the high variation in the ovarian reserve and perhaps fertility in offspring. These results support the conclusion that the inherently high variation in the ovarian reserve, potentially caused by alterations in the maternal environment, has a negative impact on ovarian function that may result in suboptimal fertility in young adult cattle, and a single AMH measurement can be used reliably in future studies to determine if fertility is suboptimal in young adult cattle with low circulating AMH concentrations and a correspondingly diminished ovarian reserve.

The reproducibility of serum anti-Müllerian hormone in subfertile women: within and between patient variability

Serum anti-Müllerian hormone concentrations vary significantly over time and this should be taken into account when tailoring treatment protocols for patients undergoing controlled ovarian hyperstimulation (COH). Compared with FSH, serum anti-Müllerian hormone may have greater discriminatory power because of its modest intrapatient variation and the larger interpatient variation.