Anti-Müllerian Hormone in Polycystic Ovary Syndrome

The role of prenatal exposure

By Megan Chmelik

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Reference

Tata B, Mimouni NEH, Barbotin AL, et al. Elevated prenatal anti-Müllerian hormone reprograms the fetus and induces polycystic ovary syndrome in adulthood. Nat Med. 2018;24(6):834-846. doi: 10.1038/s41591-018-0035-5

Design

Human retrospective correlational study and mouse treatment study

Objective

To determine whether anti-Müllerian hormone (AMH) remains elevated during pregnancy in women with polycystic ovary syndrome (PCOS) and to further investigate the association of prenatal exposure to excess AMH with PCOS incidence in offspring.

Participants

Previously collected data was obtained from the Uppsala Biobank of Pregnant Women in Sweden. Included for analysis were records of 66 pregnant women, aged 27 to 39 years, with PCOS diagnosis based on Rotterdam Criteria. Women were categorized according to BMI, androgen status, and age. Records from pregnant, healthy controls (n=63) were matched for age and BMI.

Timed-pregnant adult mice were included for initial experimentation. Those, along with their adult female offspring, were utilized for data analysis.

Intervention

Pregnant mice received injections of either phosphate-buffered saline (PBS) as the control, PBS + human recombinant prenatal AMH (PAMH), or PBS + pro-AMH (PAMH) + gonadotropin-releasing hormone (GnRH) antagonist (cetrorelix acetate) during the late gestational period (embryonic days 16.5 to 18.5). The female offspring of the PAMH-treated group received injections of PBS + GnRH antagonist during adulthood.

Outcome Measures

Pregnant women: serum AMH (pmol/L) measured during gestational weeks 16 through 19

Pregnant mice: plasma testosterone (ng/mL), luteinizing hormone (LH; ng/mL), estradiol (pg/mL), and progesterone (pg/mL)

Adult female offspring of treated mice: BMI; anogenital distance (mm); onset of puberty (vaginal opening and onset of first estrous cycle); fertility status (time of first litter following pairing, total number of litters, number of pups per litter); estrous cyclicity (time spent in each phase of the cycle); plasma testosterone and LH (ng/mL); LH pulsatility (number of pulses/2h); and ovarian histologic findings (number of corpora lutea and late antral follicles). The latter 4 measures were obtained both at puberty and after injection of GnRH.

Key Findings

Pregnant women with PCOS exhibited elevated AMH compared to pregnant controls (P≤0.0005). When stratified according to BMI (lean BMI≤25; obese BMI≥30), androgen status (normoandrogenic, hyperandrogenic), and age (27-34 years; >34 years), hyperandrogenic lean PCOS was the most likely phenotype to present with elevated AMH levels. No significant correlation was found with age.

Compared to controls, the AMH-treated adult pregnant mice had significantly higher testosterone (P=0.0023) and LH (P=0.004), and lower estradiol (P<0.0001) and progesterone (P<0.0001).

The PAMH-treated adult female offspring exhibited longer anogenital distance, delayed puberty (delayed vaginal opening and later onset of first estrous cycle), severely disrupted estrous cyclicity (decreased time in the preovulatory stage and prolonged time in metestrus and diestrus), elevated testosterone and LH, heightened LH pulsatility, abnormal ovarian histologic findings (fewer corpora lutea and late antral follicles), and impaired fertility (delay in first litter, fewer litters, fewer pups per litter) compared to controls. Following injection with the GnRH antagonist, hormone levels normalized, estrous cyclicity regulated, and ovarian histologic morphology improved.

Practice Implications

Anti-Müllerian hormone, also referred to as Müllerian-inhibiting substance, is a glycoprotein belonging to the transforming growth factor (TGF)-beta family. When produced by fetal Sertoli cells, regression of the Müllerian duct occurs and sexual differentiation of the male reproductive tract results.1 In females, the hormone is synthesized by ovarian granulosa cells in the preantral and small antral follicles.2 It inhibits recruitment of primordial follicles and follicle-stimulating hormone (FSH)–dependent growth of the small developing follicles, thus acting as a regulator of folliculogenesis.3

The present study aimed to confirm the hypothesis that AMH will remain elevated in PCOS women during pregnancy, despite the usual decline during normal pregnancy.

Past research reveals that AMH levels are higher in women with PCOS compared to those without.4,5 This is unsurprising given that a characteristic finding of PCOS is follicular excess, particularly of the preantral and small antral follicles producing AMH.6 The present study aimed to confirm the hypothesis that AMH will remain elevated in PCOS women during pregnancy, despite the usual decline during normal pregnancy.7 In addition to confirming the hypothesis, the data revealed that elevations in AMH are most significant among hyperandrogenic lean PCOS pregnant women.

The mice in this study develop hyperandrogenism and additional imbalances in LH, estradiol, and progesterone following injection with PAMH, suggesting that elevated AMH was a causative factor in the hormone dysregulation mimicking PCOS. Similar hormonal patterns and resultant abnormalities in puberty onset, estrous cyclicity, and fertility were noted in PAMH-treated offspring. This further demonstrates the contributory role that excess AMH has on the development of an inherited PCOS-like phenotype.

AMH is classically used to assess ovarian reserve, though recent research reveals its potential novel role in PCOS diagnosis.5 So far in 2018, 10 papers have been published on the diagnostic potential of AMH. Indran et al proposed a simplified PCOS criteria that replaces abnormal ovarian morphologic ultrasound findings with elevated levels of AMH. Compared with the traditional Rotterdam criteria (Rotterdam 2003), AMH used as a single diagnostic biomarker revealed poor specificity (58.9%), but the simplified criteria, which uses AMH in place of ovarian morphology, demonstrated a 94% diagnostic overlap.8 Saxena et al similarly found that AMH levels, when used adjunctively with the existing Rotterdam criteria, had promising diagnostic potential.9 In the most recent paper, Yue et al suggest the optimal diagnostic threshold is 8.16 ng/mL (20-29 years) or 5.89 ng/mL (30-39 years); however, there are discrepancies about the cutoff most appropriate for diagnosis.10,11

In the present study, prenatal cotreatment of PAMH with the GnRH antagonist cetrorelix acetate prevented offspring from acquiring the neuroendocrine and reproductive defects that mice treated with PAMH-only did. This finding suggests that “prenatal programming” of the condition is GnRH-dependent. In offspring born to PAMH mice, treatment with the GnRH antagonist led to reversal of inherited PCOS-like traits. This further supports the theory that GnRH plays a significant role in PCOS pathophysiology.

The authors of this paper suggest that GnRH antagonism may be a worthwhile therapeutic target for PCOS treatment. The restoration of ovulation and fertility that was observed in cetrorelix-treated mice is a promising finding, though it remains unclear how these outcomes will translate to humans. Treatment with GnRH antagonists like cetrorelix has been studied in the PCOS population, though only in association with assisted reproduction. A 2010 study published by the Journal of Obstetrics and Gynaecology Research reveals that GnRH antagonists, compared to GnRH agonists, are more effective, safe, and well-tolerated among those with PCOS.12 Thus, it seems reasonable to believe that GnRH antagonism may become a target for PCOS treatment.

Assuming, though prematurely, that the above mouse findings can be extrapolated to humans, lowering AMH may also be a beneficial treatment approach. Numerous studies have assessed the impact of metformin on AMH levels in women with PCOS. Findings are overall inconsistent, with reported outcomes ranging from no change at all13 to statistically significant changes.14 No correlations could be made with differing variables of each study (metformin dose, treatment duration, PCOS phenotype) and the outcomes. Several studies looked at oral contraceptives alone and compared them to metformin. Results were also mixed.15-17 Studies on the following other commonly prescribed naturopathic PCOS treatments have yielded favorable results in terms of reducing AMH: aerobic exercise,18 dietary intervention,19 weight loss,20 myo-inositol plus folic acid,18 D-chiro-inositol21 and cinnamon.22

The implications of this study are significant. The results strongly suggest a potential cause, whether sole or contributory, of PCOS, and reveal 2 novel treatment approaches. To assure that outcomes are consistent among humans, further research is necessary. Until then, continuing to recommend the tried-and-true naturopathic treatments for PCOS, many of which are highlighted above, appears worthwhile for several reasons. Doing so may not only improve symptomology in these women, but may also decrease the likelihood that their children go on to develop PCOS.

About the Author

Megan Chmelik is a third-year naturopathic medical student at National University of Natural Medicine in Portland, Oregon. Before moving to Portland, she worked for Rena Bloom, ND, and Jacob Schor, ND, FABNO, at the Denver Naturopathic Clinic. As part of a tradition of mentoring receptionists and preparing them for naturopathic school, Schor encouraged Chmelik to learn how to use PubMed and write review articles. Now years later, it is clear that this passion of his has been passed down as she continues to write for NMJ during her spare time.

References

  1. Josso N, Belville C, di Clemente N, et al. AMH and AMH receptor defects in persistent Müllerian duct syndrome. Hum Reprod Update. 2005;11(4):351-356.
  2. Rzeszowska M, Leszcz A, Putowski L, et al. Anti-Müllerian hormone: structure, properties and appliance. Ginekol Pol. 2016;87(9):669-674.
  3. Dumont A, Robin G, Catteau-Jonard S, Dewailly D. Role of anti-Müllerian hormone in pathophysiology, diagnosis and treatment of polycystic ovary syndrome: a review. Reprod Biol Endocrinol. 2015;13:137.
  4. Cook CL, Siow Y, Brenner AG, et al. Relationship between serum müllerian-inhibiting substance and other reproductive hormones in untreated women with polycystic ovary syndrome and normal women. Fertil Steril. 2002;77(1):141-146.
  5. Verma AK, Rajbhar S, Mishra J, et al. Anti-Mullerian hormone: a marker of ovarian reserve and its association with polycystic ovarian syndrome. J Clin Diagn Res. 2016;10(12):QC10-QC12.
  6. Chang RJ, Cook-Andersen H. Disordered follicle development. Mol Cel Endocrinol. 2013;373(0):51-60.
  7. Köninger A, Schmidt B, Mach P, et al. Anti-Mullerian-hormone during pregnancy and peripartum using the new Beckman Coulter AMHGen II assay. Reprod Biol Endocrinol. 2015;13:86.
  8. Indran IR, Huang Z, Khin LW, et al. Simplified 4-item criteria for polycystic ovary syndrome: a bridge too far? [published online ahead of print May 30, 2018]. Clin Endocrinol (Oxf).
  9. Saxena U, Ramani M, Singh P. Role of AMH as diagnostic tool for polycystic ovarian syndrome. J Obstet Gynaecol India. 2018;68(2):117-122.
  10. Yue CY, Lu LK, Li M, et al. Threshold value of anti-Mullerian hormone for the diagnosis of polycystic ovary syndrome in Chinese women. PLoS One. 2018;13(8):e0203129.
  11. Song DK, Oh JY, Lee H, et al. Differentiation between polycystic ovary syndrome and polycystic ovarian morphology by means of an anti-Müllerian hormone cutoff value. Korean J Intern Med. 2017;32(4):690-698.
  12. Hosseini MA, Aleyasin A, Saeedi H, et al. Comparison of gonadotropin-releasing hormone agonists and antagonists in assisted reproduction cycles of polycystic ovarian syndrome patients. J Obstet Gynaecol Res. 2010;36(3):605-610.
  13. Nascimento AD, Silva Lara LA, Japur de Sá Rosa-e-Silva AC, et al. Effects of metformin on serum insulin and anti-Mullerian hormone levels and on hyperandrogenism in patients with polycystic ovary syndrome. Gynecol Endocrinol. 201;29(3):246-249.
  14. Neagu M, Cristescu C. Anti-Műllerian hormone – a prognostic marker for metformin therapy efficiency in the treatment of women with infertility and polycystic ovary syndrome. J Med Life. 2012;5(4):462-464.
  15. Somunkiran A, Yavuz T, Yucel O, et al. Anti-Müllerian hormone levels during hormonal contraception in women with polycystic ovary syndrome. Eur J Obstet Gynecol Reprod Biol. 2007;134(2):196-201.
  16. Dursun F, Güven A, Yıldız M. Assessment of anti-Müllerian hormone level in management of adolescents with polycystic ovary syndrome. J Clin Res Pediatr Endocrinol. 2016;8(1):55-60.
  17. Ozay AC, Emekci Ozay O, Okyay RE, et al. Different effects of myoinositol plus folic acid versus combined oral treatment on androgen levels in PCOS women. Int J Endocrinol. 2016;2016:3206872.
  18. Al-Eisa E, Gabr SA, Alghadir AH. Effects of supervised aerobic training on the levels of anti-Mullerian hormone and adiposity measures in women with normo-ovulatory and polycystic ovary syndrome. J Pak Med Assoc. 2017;67(4):499-507.
  19. Foroozanfard F, Rafiei H, Samimi M, et al. The effects of dietary approaches to stop hypertension diet on weight loss, anti-Müllerian hormone and metabolic profiles in women with polycystic ovary syndrome: a randomized clinical trial. Clin Endocrinol (Oxf). 2017;87(1):51-58.
  20. Reinehr T, Kulle A, Rothermel J, et al. Weight loss in obese girls with polycystic ovarian syndrome is associated with a decrease in anti-Müllerian hormone concentrations. Clin Endocrinol (Oxf). 2017;87(2):185-193.
  21. La Marca A, Grisendi V, Dondi G, et al. The menstrual cycle regularization following D-chiro-inositol treatment in PCOS women: a retrospective study. Gynecol Endocrinol. 2015;31(1):52-56.
  22. Wiweko B, Susanto CA. The effect of metformin and cinnamon on serum anti-Mullerian hormone in women having PCOS: a double-blind, randomized, controlled trial. J Hum Reprod Sci. 2017;10(1):31-36.