[Study on the association between maternal urinary phthalate metabolites and testicular steroid hormones in the cord blood in a Chinese population].

OBJECTIVE: The purposes of our study were to investigate the association between maternal urinary phthalate metabolites and the levels of inhibin B (INHB) and insulin-like factor 3 (INSL3) in the cord blood in a Chinese pregnant population. METHODS: Maternal urine samples in the third trimester of pregnancy of 69 participants were collected and stored, and the samples of cord blood (10 ml) were collected at delivery between June 2011 and September 2012 in a comprehensive hospital of gynecology and obstetrics in Tianjin, China.Four phthalate metabolites, monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobutyl phthalate (MBP), and mono-2-ethylhexyl phthalate (MEHP) were measured in the urine samples using liquid chromatography-tandem mass spectrometry. The levels of INHB, INSL3 in the cord blood were tested by ELISA. Associations of phthalate exposure with INHB and INSL3 levels were determined by spearman correlation and multiple regression model analysis. RESULTS: The median concentrations of observed metabolites in descending order were 49.74 µg/L for MMP, 24.96 µg/L for MEHP, 19.52 µg/L for MEP and 17.73 µg/L for MBP. The median concentrations of INHB and INSL3 were 89.09 and 106.21 ng/L.Significant negative associations between INHB and MMP(ß' = -0.252), MEP(ß' = -0.363) or the sum value (∑PAEs) (ß' = -0.346) were found by the multiple regression model analysis. For INSL3, only the sum value (ß' = -0.313) was inversely significantly associated with the levels of INSL3 in the cord blood. CONCLUSIONS: Maternal urinary phthalate metabolites were associated with INHB and INSL3 in the cord blood in a Chinese population.

Food availability during migratory stopover affects testis growth and reproductive behaviour in a migratory passerine.

Long-distance migratory passerines initiate testicular recrudescence during spring migration to meet the demands of timely reproduction upon immediate arrival on the breeding grounds. The degree of testicular development is known to depend on environmental factors like stopover habitat quality; reproductive performance may be strongly impacted by testicular maturation upon arrival on the breeding grounds. We investigated the effect of stopover food availability on subsequent reproductive performance in garden warblers (Sylvia borin). Spring migration was simulated by repeated food deprivation and re-feeding to imitate the alternation of flight and stopover periods. During the two final stopover periods, males were either kept under ad libitum food (ad libitum males) or under limited food conditions (limited males). After simulated arrival in the breeding area, manipulation of previous stopover food availability resulted in significantly slower testicular recrudescence (p<0.001) and decreased plasma testosterone (p<0.01) in limited males compared to ad libitum males. Body mass change was not significantly different between the two groups (p=0.38). Limited males also exhibited reduced performance in reproductive behaviours employed in territorial and sexual contexts. Limited males had a longer 'freezing' interval (p<0.05) and decreased activity (p<0.01) when challenged with a live male decoy. In direct confrontation between limited and ad libitum males in the presence of a female, limited males exhibited significantly fewer behavioural traits in sexual context, i.e. directed to the female (p<0.001). Therefore, we suggest that conditions encountered during previous migratory stopover may affect subsequent annual reproductive success by influencing key reproductive behaviours.

Müllerian inhibiting substance: an instructive developmental hormone with diagnostic and possible therapeutic applications.

Dr. Alfred Jost pioneered the field of reproductive endocrinology with his seminal observation that two hormones produced by the testes are required for the male embryo to develop a normal internal reproductive tract. T induces the Wolffian ducts to differentiate into epididymides, vasa deferens, and seminal vesicles. Müllerian inhibiting substance (MIS) causes regression of the Müllerian ducts, which in its absence would normally develop into the Fallopian tubes, uterus, and upper vagina as is observed in female embryos. This review will summarize our current understanding of molecular mechanisms underlying the function of MIS both as a fetal gonadal hormone that causes Müllerian duct regression and as an adult hormone, the roles for which are currently being investigated, i.e., inhibition of steroidogenesis, germ cell development, and cancer. We will also address the regulation of MIS expression as one of the first genes expressed after the commitment of the bipotential gonads to differentiate into testes under the influence of SRY, the gene on the sex-determining region of the Y chromosome. We will discuss what is known regarding MIS signal transduction, which as with other members of the TGFbeta family of growth and differentiation factors, occurs through a heteromeric complex of single transmembrane serine/threonine kinase receptors to effect downstream signaling events, including Smad, nuclear factor-kappaB, beta-catenin, and p16 activation. Finally, we will assess the clinical relevance of studying MIS in patients with persistent Müllerian duct syndrome and our efforts to determine the therapeutic value of MIS for patients with ovarian and other MIS receptor-expressing cancers.

Mullerian inhibiting substance: a gonadal hormone with multiple functions.

Mullerian inhibiting substance (MIS) is the gonadal hormone that causes regression of the Mullerian ducts, the anlagen of the female internal reproductive structures, during male embryogenesis. MIS is a member of the large transforming growth factor-beta (TGF beta) multigene family of glycoproteins that are involved in the regulation of growth and differentiation. The proteins in this gene family are all produced as dimeric precursors and undergo posttranslational processing for activation, requiring cleavage and dissociation to release bioactive C-terminal fragments. Similarly, the 140 kilodalton (kDa) disulfide-linked homodimer of MIS is proteolytically cleaved to generate its active C-terminal fragments. The sexually dimorphic expression of MIS in Sertoli cells of the testis and granulosa cells of the ovary is critical for normal differentiation of the internal reproductive tract structures. A number of extra-Mullerian functions such as control of germ cell maturation and gonadal morphogenesis, induction of the abdominal phase of testicular descent, suppression of lung maturation, and growth inhibition of transformed cells have also been proposed for this growth-inhibitory hormone and will be discussed. This article will summarize the current understanding of the biology and multiple functions of MIS including its activation, regulation, and mechanism of action and discuss areas of interest in ongoing research.

Importance of Serum Testicular Protein Hormone Measurement in the Assessment of Disorders of Sex Development.

Commonly known for testosterone secretion, the testes also produce the protein hormones anti-müllerian hormone (AMH), inhibin B, and insulin-like factor 3 (INSL3). AMH and inhibin B are secreted by Sertoli cells, whereas INSL3 is a Leydig cell product. AMH is involved in fetal sex differentiation and induces the regression of the anlagen of the uterus and fallopian tubes. INSL3 participates in fetal testicular descent. Serum testicular protein hormone assessment can be very useful and complementary to testosterone measurements in patients with DSD. AMH and inhibin B determination is extremely helpful during childhood, when basal testosterone is normally low. Serum AMH and inhibin B above the female range are indicative of the presence of testicular tissue, and their circulating levels reflect the amount of functional Sertoli cells. In DSD patients with normal male levels of AMH and inhibin B, the diagnosis of gonadal dysgenesis can be ruled out, and isolated androgen secretion deficiency or androgen insensitivity should be suspected. In externally virilized XY patients with persistent müllerian ducts, serum AMH levels determine the diagnosis to AMH deficiency or resistance. At pubertal age, inhibin B levels serve to predict spermatogenic development.

Oxandrolone Treatment Results in an Increased Risk of Gonadarche in Prepubertal Boys With Klinefelter Syndrome.

Context: Klinefelter syndrome (KS) is a common genetic condition in which males have an extra X chromosome. KS is associated with testosterone deficiency, neurodevelopmental delays, and cardiometabolic disorders. There has been recent interest in prepubertal androgen treatment; however, the effects on puberty and gonadal function are unknown. Objective: To compare onset of puberty and testicular function in prepubertal boys treated with 2 years of oxandrolone (Ox) vs placebo (Pl). Design: Double-blind, randomized, controlled trial. Setting: Single tertiary care referral center. Participants: Eighty prepubertal boys with KS; mean age: 8.0 ± 2.2 years (range: 4 to 12). Interventions: Ox 0.05 mg/kg vs identical-appearing Pl capsule given for 2 years. Outcome Measures: Onset of gonadarche (testicular volume ≥4 mL) and onset of pubarche (Tanner 2 pubic hair); change in testicular hormone concentrations. Results: Ox-treated group had 20.5 times higher odds of reaching gonadarche (OR 95% CI: 6.5, 77.8) and 28.1 times higher odds of reaching pubarche (OR 95% CI: 8.8, 110.4) during the 2-year study period after adjusting for baseline age. Gonadarche and pubarche both occurred at a younger age in the Ox group (gonadarche: 9.8 ± 1.5 vs 12.1 ± 1.0 years, P < 0.001; pubarche: 10.2 ± 1.1 vs 11.6 ± 1.3 years, P = 0.02). Serum concentrations of testicular hormones and gonadotropins were not different between groups. Conclusions: Two years of Ox treatment in prepubertal boys with KS results in an increased risk of early gonadarche, on average 2 years earlier than in Pl-treated boys. Ox did not affect serum concentrations of testicular hormones.

Increased oocyte degeneration and follicular atresia during the estrous cycle in anti-Müllerian hormone null mice.

Anti-Müllerian hormone (AMH) plays an important role in folliculogenesis. AMH null mice display an increased recruitment of primordial follicles. Nevertheless, these mice do not have proportionally more preovulatory follicles. Therefore, AMH null mice provide an interesting genetic model to study the regulation of species-specific number of preovulatory follicles. We studied the follicle pool throughout the estrous cycle at 4 months of age. Analysis of the follicle pool revealed that AMH null mice have an increased and earlier cyclic recruitment of growing follicles despite a blunted FSH surge at estrus. However, FSH levels at estrus were apparently too low to support growth to the preovulatory stage because an increased level of atresia was observed, which neutralized the increased cyclic recruitment. When AMH null mice were subjected to a superovulation scheme, the rise in FSH levels resulted in the rescue of the recruited cohort of growing follicles. Analysis of the follicle pool also revealed that the increased recruitment of primordial follicles in AMH null mice was neutralized by an increased loss of follicles during the transition from small preantral to large preantral follicle. This major loss of follicles was not completely reflected by a corresponding augmentation of atresia but did correspond with an increased number of oocyte remnants observed in AMH null mice. We conclude that a combination of increased oocyte degeneration and increased follicular atresia neutralizes the increased initial and cyclic recruitment in AMH null mice to a normal number of preovulatory follicles.

Anti-Müllerian hormone levels in peripubertal daughters of women with polycystic ovary syndrome.

CONTEXT: We have previously observed increased anti-Müllerian hormone (AMH) levels in prepubertal daughters of polycystic ovary syndrome (PCOS) women, suggesting that these girls may have an altered follicular development. However, it is not known whether AMH levels remain increased during puberty. OBJECTIVE: The aim was to establish whether the increased AMH levels observed in prepubertal daughters of PCOS women persist during the peripubertal period, a stage during which the gonadal axis is activated and PCOS may become clinically manifested. DESIGN: We studied 28 daughters (8-16 yr old) of PCOS women (PCOSd) and 33 daughters (8-16 yr old) of control women (Cd). In both groups, an oral glucose tolerance test was performed. Gonadotropins, sex hormones, and AMH were determined in a fasting sample. RESULTS: Both groups were comparable in age, body mass index, and breast Tanner stage. Free androgen index, testosterone, AMH (Cd 14.4 +/- 8.0 pM vs. PCOSd 24.0 +/- 19.0 pM; P = 0.012), and 2-h insulin levels were significantly higher in the PCOSd group compared with the control group. The average ovarian volume was significantly higher in the PCOSd group. In both groups a positive correlation between 2-h insulin and AMH concentrations was observed (PCOSd: r = 0.530, P = 0.007; Cd: r =0.561, P = 0.008). CONCLUSIONS: AMH concentrations are increased in peripubertal PCOSd. These findings, along with the results of our previous study, suggest that PCOSd appear to show an increased follicular mass that is established during early development, and persists during puberty.

Serum anti-mullerian hormone concentrations are not altered by acute administration of follicle stimulating hormone in polycystic ovary syndrome and normal women.

CONTEXT: In the human ovary, expression of anti-Mullerian hormone (AMH) is detected primarily in granulosa cells of preantral and small antral follicles. This finding is consistent with the tight correlation between circulating AMH levels and the number of small antral follicles (2-5 mm) in normal and polycystic ovary syndrome (PCOS) women. In addition, the greater follicle count in PCOS is mirrored by significantly higher serum AMH levels compared with those of normal women. Despite the utility of AMH measurements in evaluating ovarian physiology and function, the regulation of AMH remains poorly understood. OBJECTIVE: The objective was to determine whether gonadotropins acutely regulate serum AMH in women with PCOS and normal women. DESIGN: We conducted a prospective study to compare ovarian responses to FSH in two groups of women. SETTING: The study was conducted in a General Clinical Research Center in a tertiary academic medical center. PATIENTS: Women with PCOS (age, 18-35 yr; n = 16) and normal ovulatory controls (age, 18-35 yr; n = 11) were recruited for study. INTERVENTIONS: Serum samples were measured over a 24-h period after an iv injection of recombinant human FSH (150 IU). MAIN OUTCOME MEASURE(S): Serum AMH responses after FSH administration were measured. RESULTS: Basal serum AMH levels were markedly increased in women with PCOS compared with levels observed in normal women. After FSH injection, PCOS women failed to demonstrate changes in circulating AMH over 24 h. A similar lack of alteration in serum AMH was observed in normal women. CONCLUSIONS: These findings suggest that in PCOS and normal women, acute exposure to FSH does not appear to exert an effect on AMH production.

Endocrine features of menstrual cycles in middle and late reproductive age and the menopausal transition classified according to the Staging of Reproductive Aging Workshop (STRAW) staging system.

CONTEXT: Female reproductive aging based on changes in menstrual cycle length and frequency progresses through a number of stages as defined by the Stages of Reproductive Aging Workshop (STRAW) staging criteria. OBJECTIVE: This paper provides a comprehensive description of the endocrine features associated with the STRAW stages. DESIGN: Healthy women aged 21-35 and 45-55 yr submitted three blood samples a week over a single menstrual cycle. They were classified as mid-reproductive age (n = 21), late-reproductive age (n = 16), early menopause transition (n = 16), and late menopause transition (n = 23). RESULTS: There were nine, one, zero, and two anovulatory cycles identified in the late menopause transition, early menopause transition, late-reproductive age, and mid-reproductive age groups, respectively. Ovulatory cycle FSH, LH, and estradiol levels increased with progression of STRAW stage (P = 0.001, P < 0.01, and P < 0.05, respectively), and mean luteal phase serum progesterone decreased (P < 0.01). Early cycle (ovulatory and anovulatory) inhibin B decreased steadily across the STRAW stages (P < 0.01) and was largely undetectable during elongated ovulatory and anovulatory cycles in the menopause transition. Anti-Mullerian hormone decreased markedly (10- to 15-fold) and progressively across the STRAW stages (P < 0.01 and P < 0.001, respectively). CONCLUSIONS: Progression through the STRAW stages is associated with elevations in serum FSH, LH, and estradiol and decreases in luteal phase progesterone. The marked fall in inhibin B and particularly anti-Mullerian hormone indicate that they may be useful in predicting STRAW stage but future analyses of early cycle measurements on larger cohorts are needed to draw predictive conclusions.

Heterozygous mutation of steroidogenic factor-1 in 46,XY subjects may mimic partial androgen insensitivity syndrome.

CONTEXT: The clinical and biological features of Sertoli cell and Leydig cell dysfunction are usually investigated when characterizing disorders of sex development in 46,XY individuals: This allows gonadal dysgenesis, a defective development of the gonad, to be distinguished from defects restricted to androgen synthesis or sensitivity. In humans, mutations in steroidogenic factor-1 (SF-1), one of the critical factors involved in testis development, have been reported to cause gonadal dysgenesis with or without adrenal failure in 46,XY individuals. OBJECTIVE: We report a SF-1 mutation that caused ambiguous genitalia associated with strikingly different hormonal phenotypes in two affected 46,XY children from the same family. METHODS: Hormonal evaluation included testosterone (T), anti-Mullerian hormone (AMH), inhibin B, FSH, and LH measurements during the first weeks of life, a period when physiological activation of the gonadotropin-gonadal system occurs. Direct DNA sequencing of the coding sequence of the SF-1 and the androgen receptor (AR) genes was performed. RESULTS: Both 46,XY children had ambiguous genitalia with no Mullerian structures and no adrenal insufficiency. The older child showed normal elevation of T (up to 7.6 nmol/liter, 2.2 ng/ml), AMH (504 pmol/liter, 70.6 ng/ml), inhibin B (245 pg/ml), FSH, and LH during the first weeks, which led to a presumptive diagnosis of partial androgen insensitivity syndrome. The AR sequence was, however, normal. In the second child, T, AMH, and inhibin B were low, suggesting gonadal dysgenesis. In both children and their mother, a c.536delC frameshift mutation in the SF-1 gene was found. This mutation terminates translation at position 295, removing the ligand-binding domain and the activation function 2 (AF-2) domain, a critical domain for SF-1 transactivating activity. CONCLUSIONS: The usual markers of testis dysgenesis may be normal in 46,XY individuals with SF-1 mutation. Screening for SF-1 mutation should be performed in subjects with apparent partial androgen insensitivity syndrome and no mutation in the AR gene.

Anti-Müllerian hormone concentrations in the follicular fluid of the preovulatory follicle are predictive of the implantation potential of the ensuing embryo obtained by in vitro fertilization.

CONTEXT: The strong relationship between serum anti-Müllerian hormone (AMH) levels and the number of antral follicles supports the use of AMH measurements as a quantitative marker of the ovarian follicular status. Yet, it still is unclear whether the aptitude of an individual follicle to produce AMH reflects its reproductive competence. OBJECTIVE: This study examined the possible relationship between serum or follicular fluid (FF) AMH concentrations and the fate of the ensuing oocytes and embryos obtained by in vitro fertilization-embryo transfer conducted in monodominant follicle cycles. DESIGN AND SETTING: We conducted a prospective study at the University of Paris XI, Assistance Publique-Hôpitaux de Paris, Institut National de la Santé et de la Recherche Médicale U782. PATIENTS: Patients included 118 infertile in vitro fertilization-embryo transfer candidates. INTERVENTIONS: Concentrations of AMH, progesterone, and estradiol were measured in the serum on cycle d 3 and on the day of oocyte pickup (dOPU), and in FF. Cycles were sorted into three sets of three distinct groups according to whether serum d 3, serum dOPU, and FF AMH concentrations were 30th centile or below (low AMH), between the 31st and the 70th centiles (average AMH), or above the 70th centile (high AMH) of measurements. MAIN OUTCOME MEASURE: Clinical pregnancy and embryo implantation rates were assessed. RESULTS: Clinical pregnancy rates (5.7, 20.0, and 39.5%, respectively; P < 0.002) and embryo implantation rates (11.8, 30.8, and 65.4, respectively; P <0.001) were markedly different among the low, moderate, and high FF AMH groups but not among the serum (d 3 or dOPU) AMH groups. Fertilization rates and embryo morphology remained similar irrespective of AMH concentrations in the serum or in FF. Incidentally, FF AMH concentrations were negatively correlated with FF progesterone (r = -0.27; P <0.003) and FF estradiol (r = -0.21; P <0.02) concentrations. CONCLUSIONS: Concentrations of AMH in the FF, but not in the serum, constitute a useful follicular marker of embryo implantation and are negatively related to FF progesterone and estradiol concentrations.

Hormonal and cellular regulation of Sertoli cell anti-Müllerian hormone production in the postnatal mouse.

Anti-Müllerian hormone (AMH) is secreted by immature testicular Sertoli cells. Clinical studies have demonstrated a negative correlation between serum AMH and testosterone in puberty but not in the neonatal period. We investigated AMH regulation using mouse models mimicking physiopathological situations observed in humans. In normal mice, intratesticular, not serum, testosterone repressed AMH synthesis, explaining why AMH is downregulated in early puberty when serum testosterone is still low. In neonatal mice, AMH was not inhibited by intratesticular testosterone, due to the lack of expression of the androgen receptor in Sertoli cells. We had shown previously that androgen-insensitive patients exhibit elevated AMH in coincidence with gonadotropin activation. In immature normal and in androgen-insensitive Tfm mice, follicle stimulating hormone (FSH) administration resulted in elevation of AMH levels, indicating that AMH secretion is stimulated by FSH in the absence of the negative effect of androgens. The role of meiosis on AMH expression was investigated in Tfm and in pubertal XXSxrb mice, in which germ cells degenerate before meiosis. We show that meiotic entry acts in synergy with androgens to inhibit AMH. We conclude that AMH represents a useful marker of androgen and FSH action within the testis, as well as of the onset of meiosis.

Factors and markers of growth hormone secretion and gonadal function in Fanconi anemia.

UNLABELLED: Many factors may be involved in the growth and gonadal dysfunction of Fanconi anemia (FA). OBJECTIVE: To evaluate the (1) relationship between FA presentation, including genital abnormalities and pituitary stalk interruption syndrome (PSIS), (2) markers of growth hormone (GH) deficiency and gonadal function, and (3) factors influencing final height and gonadal function. PATIENTS: Twenty five patients with FA were included, 17 of them were given bone marrow transplantation. RESULTS: Six patients were diagnosed with GH deficiency and PSIS (group A), whereas 19 had no evidence of GH deficiency (group B). In group A, all patients had more than 3 FA malformations and all 5 boys had cryptorchidism associated with microphallus in 4. All patients had heights and plasma insulin-like growth factor I < -3SD. Final height was reached in 15 patients and was < or = -2SD in 12 of them, all but 3 were born small for gestational age and/or given norethandrolone and/or corticosteroids. Gonadal function was abnormal in 5/7 boys and 4/5 girls evaluated at pubertal age. The plasma concentrations were low in 4/9 for antimüllerian hormone and in 3/9 for inhibin B, 3 of them had been given bone marrow transplantation. CONCLUSIONS: PSIS can be part of a severe FA phenotype. It seems to occur mainly in boys, with more than 3 malformations, microphallus and cryptorchidism. This phenotype is associated with normal blood counts, defining a new clinical subgroup of patients.

Müllerian inhibiting substance and disrupted folliculogenesis in polycystic ovary syndrome.

OBJECTIVE: This study determines whether pretreatment levels of müllerian inhibiting substance/antimüllerian hormone (MIS/AMH) would reflect ovarian response to exogenous gonadotropin in women with polycystic ovary syndrome (PCOS) and ovulatory controls matched by age and weight. STUDY DESIGN: Case-control study of 20 women with PCOS and 10 normoovulatory women undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) at an academic medical center. RESULTS: Baseline serum MIS/AMH levels in PCOS were higher than those of normoovulatory women (P < .001). MIS/AMH levels increased after gonadotropin-releasing hormone (GnRH) agonist pituitary suppression; 0.5 ng/mL in PCOS (P = .12) and 0.7 ng/mL in controls (P < .02). In normoovulatory women, MIS/AMH at baseline, after pituitary suppression, and the interval change after pituitary suppression all correlated closely to the number of mature oocytes retrieved (P < .005). In PCOS, however, levels of MIS/AMH at baseline and after pituitary suppression did not show this correlation, whereas only the interval change correlated with the number of mature oocytes retrieved. CONCLUSION: Baseline MIS/AMH is a good predictor of the ovarian response to COH in normoovulatory women but not in PCOS.

Measurement of serum anti-Müllerian hormone by Beckman Coulter ELISA and DSL ELISA: comparison and relevance in assisted reproduction technology (ART).

BACKGROUND: Numerous studies have evocated the clinical usefulness of serum AMH levels as a predictor of ovarian response and pregnancy in assisted reproductive technology cycles. Nevertheless, the analysis of the literature shows a great dispersion in serum AMH concentrations obtained with different methods from almost comparable populations. METHODS: We compared two commercial immunoassays (AMH Beckman Coulter ELISA and AMH DSL ELISA) and we evaluated the AMH levels in serum as a prognosis value for ovarian response and pregnancy in assisted reproductive technology cycles. RESULTS: We found a close linear relationship between the two methods but AMH levels were almost 4.6-fold lower with the DSL kit than with the Beckman Coulter kit. We found a significant and positive correlation between the number of mature ovocytes inseminated and AMH levels obtained with the two methods. Whatever the ELISA used, we found no significant difference between AMH level of pregnancy and non pregnancy groups. Indeed, using the Beckman Coulter method, all pregnant patients had serum AMH levels over 1.4 microg/L. Conversely, no cut-off value can be found for the DSL kit. CONCLUSION: Our results show clearly for the first time that AMH results are method dependent even if the correlation obtained between the two methods remained excellent. The Beckman Coulter AMH ELISA should produce clinical agreement when used for prognosis purposes on patients undergoing assisted reproduction.

Gonadal function in low birth weight infants: a pilot study.

OBJECTIVE: To evaluate gonadal function and anti-Müllerian hormone (AMH) serum concentrations during the first 3 months of life in low birth weight (low-BW) and normal birth weight (normal-BW) infants. INFANTS: Twenty low-BW and 29 normal-BW infants were studied. METHODS: The pituitary-gonadal axis was evaluated by a GnRH agonist test (leuprolide acetate, 10 microg/kg s.c.). Circulating concentrations of gonadotropins, steroid hormones, sex hormone binding globulin, inhibin B and AMH were determined by specific assays. RESULTS: In both sexes, basal concentrations of gonadotropins, sex steroids, sex hormone binding globulin and inhibin B were similar between low-BW and normal-BW infants. However, AMH concentrations were significantly higher in low-BW compared to normal-BW females (p = 0.004). This was not observed in males. After leuprolide administration, estradiol concentrations were higher in low-BW compared to normal-BW females (p = 0.043). In males, post-stimulated sex steroid concentrations were similar in both groups except for 17-OHP, which was significantly higher after leuprolide in the low-BW group (p = 0.023). CONCLUSIONS: An increase in AMH and post-stimulated estradiol serum concentrations suggests altered follicular development in low-BW girls. In contrast, the normal circulating levels of AMH and inhibin B seem to indicate that Sertoli cell function is normal in low-BW boys. We suggest that ovarian function seems to be more vulnerable than testicular function in infants with intrauterine growth restriction.

The Testicular Hormones AMH, InhB, INSL3, and Testosterone Can Be Independently Deficient in Older Men.

BACKGROUND: Late-onset hypogonadism is symptomatically diverse and not fully explained by circulating testosterone level. The adult testes secrete four distinct hormones (testosterone, AMH, INSL3, and InhB) into the circulation. Testosterone and InhB have proven dynamic regulation, with limited information available for AMH and INSL3. During aging, there is cellular senescence, which may underlie the diversity of hypogonadism. This leads to the postulate that the relative levels (profile) of the four testicular hormones in older men are variable and cannot be evaluated by the measurement of one hormone. METHODS: 111 men aged 19-50 years and 98 men aged 70-90 years were examined. The circulating levels of the testicular hormones were measured using ELISAs, and the variation in the levels of hormones was analyzed by various correlative analyses. RESULTS: All four hormones were largely or totally independent. Some men were deficient in multiple hormones, but no man had multiple elevated hormones. The average hormonal levels were lower in older men, with diverse profiles of the four testicular hormones. Hence, some men had one or more hormones below the reference range, with testosterone the most conserved. Consequently, testosterone levels were not indicative of the complete state of the endocrine testes. CONCLUSIONS: The four hormones vary independently of each other, in younger and older men. This indicates that they are regulated dynamically rather than influenced by endocrine cell number. Older men exhibited diverse profiles of low levels of testicular hormones, suggesting that the testes age differently between men. Testosterone alone inadequately describes gonadal states.

Serum anti-mullerian hormone levels reflect the size of the primordial follicle pool in mice.

Reproductive aging is the decline of female fertility with age. It is caused by the decrease in the number of growing follicles, resulting from primordial follicle pool depletion. Recently, we have shown that anti-Müllerian hormone (AMH) is produced by growing follicles, and studies in women indicate that serum AMH levels decrease with age and correlate with antral follicle count. However, whether serum AMH levels correlate directly with the size of the primordial follicle pool cannot be determined in women. In this work, we describe studies in mice in which we determined the dynamics of ovarian follicles during aging. Furthermore, we describe the development of a mouse AMH ELISA, allowing us to measure AMH levels in mice, for the first time. We observed that serum AMH levels decline with increasing age, whereas expression of AMH in individual growing follicles, studied by immunohistochemistry, did not change with age. Thus, the decline in serum AMH correlates directly with the decline in the number of growing follicles (r = 0.86, P < 0.0001). We observed that the number of growing follicles correlated with the number of primordial follicles (r = 0.93, P < 0.0001). Similarly, we found a strong correlation between AMH levels and number of primordial follicles (r = 0.83, P < 0.0001). In conclusion, serum AMH levels reflect the size of the primordial follicle pool in aging mice. Therefore, AMH is an excellent marker to assess the quantitative aspect of ovarian reserve, which may be useful for women at risk for early ovarian aging such as survivors of childhood cancers.

Anti-Müllerian hormone levels in the spontaneous menstrual cycle do not show substantial fluctuation.

CONTEXT: Anti-Müllerian hormone (AMH), a quantitative marker for ovarian reserve, has been suggested to be independent of the classical endocrine fluctuations of the menstrual cycle. OBJECTIVE: The objective of the study was to determine whether AMH levels are constant throughout the menstrual cycle, compared with those of FSH, LH, and estradiol. DESIGN/PATIENTS: Frequent blood sampling was performed in 44 fertile, regularly cycling, female volunteers during one full menstrual cycle. SETTING: The study was conducted at a university hospital. MAIN OUTCOME MEASURES: AMH, FSH, LH, and estradiol measurements were allocated to one of seven cycle phases, and a multilevel analysis was performed. Consistent fluctuation patterns were tested by fitting sine patterns to the data. Finally, the frequency in which randomly selected individual samples would remain in one of five preset level categories (quintiles) for each of the variables was studied. RESULTS: A sine pattern fitted to the AMH data was not statistically significant (P = 0.40). In contrast, sine patterns for FSH, LH, and estradiol were highly significant. Comparing the seven cycle phases, no significant differences could be observed between phase-specific AMH levels (P = 0.06). Repeated selection of AMH samples for each individual showed that in 71.5% of selections, AMH values remained in the same quintile, whereas in 27.9% values fell in an adjacent quintile. CONCLUSIONS: AMH levels measured through a full menstrual cycle did not show consistent fluctuation patterns in contrast to levels of FSH, LH, and estradiol. Furthermore, random fluctuations were small, indicating that AMH can be relied on as a cycle-independent marker for ovarian reserve.