'The effect of weight loss on anti-müiierian hormone levels in overweight and obese women with

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1 The effect of weight loss on anti-müiierian hormone levels in overweight and obese women with polycystic ovary syndrome and reproductive impairment This is the author submitted original manuscript (pre-print) version of a published work that appeared in final form in: Buckley, JD, Thomson, R L, Moran, LJ, Noakes, M, Clifton, PM, Norman, RJ & Brinkworth, GD 2009 'The effect of weight loss on anti-müiierian hormone levels in overweight and obese women with polycystic ovary syndrome and reproductive impairment' Human reproduction, vol. 24, no. 8, pp Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms are not reflected in this document and it does not replicate the final published authoritative version for which the publisher owns copyright. It is not the copy of record. This output may be used for non-commercial purposes. The final definitive published version (version of record) is available at: Persistent link to the Research Outputs Repository record: General Rights: Copyright and moral rights for the publications made accessible in the Research Outputs Repository are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognize and abide by the legal requirements associated with these rights. Users may download and print one copy for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the persistent link identifying the publication in the Research Outputs Repository If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

2 The Library Educating Professionals, Creating and Applying Knowledge, Engaging our Communities This is the author s (pre print) version of a published work that appeared in final form in Human Reproduction, vol. 24, no. 8, pp , copyright 2009 The Author. Changes resulting from the publishing process, such as peer review, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. This article is copyright and may be used for non-commercial purposes. Refer to the published work for the definitive version.

3 1 1 2 The effect of weight loss on anti-müllerian hormone levels in overweight and obese women with polycystic ovary syndrome and reproductive impairment 3 4 Running Title: Weight loss and AMH in PCOS R.L. Thomson 1,2, J.D. Buckley 1, L.J. Moran 2, M. Noakes 2, P.M. Clifton 2, R.J. Norman 3, G.D. Brinkworth Australian Technology Network Centre for Metabolic Fitness & Nutritional Physiology Research Centre, Sansom Institute for Health Research, University of South Australia, Adelaide, Australia, Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organisation, Human Nutrition, Adelaide, Australia, Research Centre for Reproductive Health, Robinson Institute, University of Adelaide, Adelaide, Australia, Corresponding Author: Dr. Grant Brinkworth CSIRO Human Nutrition PO Box BC Adelaide, South Australia 5000 Tel: Fax: grant.brinkworth@csiro.au 24 Clinical Trials Registration Number: ACTRN

4 2 25 Abstract BACKGROUND: Anti-müllerian hormone (AMH) has been proposed as a clinical predictor of improvements in reproductive function following weight loss in overweight and obese women with polycystic ovary syndrome (PCOS). This study aimed to assess whether baseline and/or change in AMH with weight loss predict improvements in reproductive function in overweight and obese women with PCOS. METHODS: Fifty-two overweight and obese women with PCOS and reproductive impairment (age 29.8 ± 0.8 yrs, BMI 36.5 ± 0.7 kg/m 2 ) followed a 20 week weight loss program. AMH, weight, menstrual cyclicity and ovulatory function were assessed at baseline and post-intervention. RESULTS: Participants that responded with improvements in reproductive function (n = 26) had lower baseline AMH levels (23.5 ± 3.7 pmol/l v 32.5 ± 2.9 pmol/l; P = 0.03) and experienced greater weight loss (-11.7 ± 1.2 kg v -6.4 ± 0.9 kg; P = 0.001) compared with those that did not respond (n = 26). Logistic regression analysis showed that weight loss and baseline AMH were independently related to improvements in reproductive function ((P = and P = respectively). AMH levels did not change with weight loss in both responders and non-responders. CONCLUSION: In overweight and obese women with PCOS and reproductive dysfunction, a 20 week weight loss intervention resulted in improvements in reproductive function but no change in AMH levels Key Words: weight loss, anti-müllerian hormone, reproductive function, menstrual cyclicity 45

5 Introduction Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility in women of reproductive age, affecting approximately 7% of this population (Norman, et al., 2007). It is associated with insulin resistance, elevated androgens and reproductive problems including infertility and menstrual dysfunction (Norman, et al., 2007). Although not entirely understood, the aetiology of PCOS is closely linked to obesity and abdominal adiposity that are considered to worsen the clinical presentation, particularly menstrual irregularities and hyperandrogenism (Holte, et al., 1995, Pasquali, et al., 2006, Barber, et al., 2006). Lifestyle modification programs focusing on weight loss have been shown to be important for improving reproductive function in obese women with PCOS (Huber-Buchholz, et al., 1999, Crosignani, et al., 2003, Moran, et al., 2003). However several studies have demonstrated that reproductive responsiveness to weight loss (shown by improved menstrual cyclicity or ovulation) only occurs in ~60% of previously anovulatory overweight women (Holte, et al., 1995, Huber-Buchholz, et al., 1999, Crosignani, et al., 2003, Moran, et al., 2003, Kiddy, et al., 1992) Anti-Müllerian hormone (AMH), a member of the transforming growth factor-β family, is expressed in the granulosa cells of early developing follicles in the ovary and is an inhibitor of follicular maturation and recruitment. Women with PCOS have 2-to 3-fold higher levels of AMH compared to healthy women (Piltonen, et al., 2005, Pigny, et al., 2006, La Marca, et al., 2004, Cook, et al., 2002, Laven, et al., 2004, Pigny, et al., 2003). AMH is secreted by small antral follicles and elevated AMH in PCOS reflects both an increased number of these follicles due to a disturbance in the selection of the dominant follicle (Laven, et al., 2004, Pigny, et al., 2003, Visser, et al., 2006) as well as an increase in production of AMH per granulosa cell, with the latter possibly related to intrinsic features of PCOS or an altered level

6 of regulatory factors (Pellatt, et al., 2007). Recently our group has shown that pre-treatment AMH levels may be a clinical predictor of reproductive responsiveness to weight loss in overweight and obese women with PCOS (Moran, et al., 2007). Women who experienced menstrual improvements exhibited significantly lower baseline AMH levels compared to women who had no menstrual improvements (Moran, et al., 2007). However, this study did not assess changes in AMH levels following weight loss Reductions in AMH levels with metformin therapy have been reported in women with PCOS (Piltonen, et al., 2005, Fleming, et al., 2005). Increasing serum follicle stimulating hormone (FSH) concentrations through low-dose recombinant FSH therapy has also been associated with reduced AMH levels in anovulatory women with PCOS which suggests inhibition of follicular function and growth, allowing the emergence of a dominant follicle (Catteau- Jonard, et al., 2007). Serum AMH levels have also decreased during controlled ovarian stimulation (Fanchin, et al., 2003, Eldar-Geva, et al., 2005, La Marca, et al., 2004), possibly involving follicular development, through the reduction in small antral follicles (Fanchin, et al., 2003) or FSH-stimulated growth of larger follicles that lose their AMH expression (La Marca, et al., 2004). To date no study has examined the effects of weight loss on AMH and whether improvements in reproductive function with weight loss are associated with reductions in AMH. Therefore the aim this study was to confirm the findings of our earlier study and extend this work to determine whether improvements in reproductive function with weight loss in obese women with PCOS were accompanied by changes in AMH Material and Methods Participants

7 overweight and obese women with PCOS and reproductive impairment (age 29.2 ± 0.9 yrs, body mass index (BMI) 36.2 ± 0.8 kg/m 2 ) were recruited by public advertisement and from general practitioner and specialist clinics. PCOS was diagnosed according to the current Rotterdam criteria (The Rotterdam ESHRE/ASRM-sponsored PCOS consensus workshop group, 2004). Polycystic ovaries were identified by transvaginal or transabdominal ultrasound examination and clinical hyperandrogenism by elevated testosterone (>2.0 nmol/l) and/or free androgen index (>5.4). Reproductive impairment was identified by menstrual irregularity (defined as cycle lengths < 21 days or > 35 days, or variation between consecutive cycles of > 3 days) and/or non-ovulatory status Potential participants were excluded if they were using fertility treatments, metformin or oral contraceptives, were smokers, pregnant, breastfeeding or had a history of cardiovascular, liver, kidney or respiratory disease, diabetes, uncontrolled hypertension, or a malignancy. Exclusion criteria also included not being weight stable (< 3 kg change in 3 months) or following a weight reducing diet within 3 months prior to study commencement or the presence of any reproductive disorders unrelated to PCOS, thyroid abnormalities or nonclassical adrenal hyperplasia. The protocol and potential risks and benefits of the study were explained to participants before they provided written informed consent. All experimental procedures were approved by the Human Ethics Committees of the Commonwealth Scientific and Industrial Research Organisation and the University of South Australia Study Design Participants were prescribed a hypocaloric dietary program (~6000 kj/day) for 20 weeks. Before (baseline) and after the 20 week weight loss intervention participants attended the clinic after an overnight fast and had height (baseline only), body weight and waist

8 circumference measured prior to the collection of a venous blood sample for the measurement of glucose, insulin, testosterone, sex-hormone binding globulin (SHBG) and AMH. Participants were advised not to consume any alcohol or participate in vigorous physical activity during the 24 hours prior to these visits. During the month prior to study commencement and throughout the intervention, menses calendars were recorded to assess menstrual cyclicity and first morning spot urine samples were collected twice-weekly to assess pregnanediol-3-glucuronide (PDG) concentrations as a marker of ovulation. Following the intervention, participants were identified as responders (n = 26) and non-responders (n = 26) according to their changes in reproductive impairment. Responders were identified as having either improvement in ovulatory function (defined as a change from non-ovulatory cycles to ovulatory cycles) and/or improvements in menstrual status (defined as a change from irregular cycles to regular cycles or an improvement in consecutive intercycle variation). Non-responders had no change in menstrual cyclicity and ovulatory function status from baseline Clinical and biochemical measurements Height and body weight were measured using a stadiometer (SECA, Hamburg, Germany) and electronic digital scales (Mercury, AMZ 14, Tokyo, Japan), respectively. BMI was calculated as weight (kg)/height (m) 2. Waist circumference was measured 2 cm above the uppermost lateral border of the iliac crest using an anthropometric tape (model W606PM, Lufkin, Houston, TX, USA). The average of 3 measurements was used as the measured value. Fasting plasma and serum samples were collected and stored at -80 o C for analysis following study completion. Plasma glucose was measured on a Hitachi 902 auto-analyzer (Roche Diagnostics, Indianapolis, Indiana) using commercial enzymatic kits (Roche Diagnostics, Basel, Switzerland). Plasma insulin concentrations were determined using a commercial

9 enzyme-linked immunoassay kit (Mercodia ELISA, ALPCO Diagnostics, Uppsala, Sweden). Insulin resistance was estimated using the homeostasis model assessment online calculator (HOMA2) (Wallace, et al., 2004). SHBG was measured by coated-tube immunoradiometric assay using commercial kits (Diagnostic System Laboratories, Webster, Texas). Testosterone was measured by radioimmunoassay using commercial enzymatic kits (Diagnostic System Laboratories, Webster, Texas). Free Androgen Index (FAI) was calculated as testosterone/shbg x 100. Plasma AMH was measured using an Immunotech immunoenzymatric assay (Beckman Coulter, Marseille, France) Spot urine samples were stored at -20 o C until analysis at completion of the study. Urinary PDG was measured according to the method of Santoro et al. (Santoro, et al., 2003). Menses calendars were used to assess menstrual cyclicity and cross-referenced with PDG peaks to confirm the presence of ovulation Data analysis Data were checked for normality prior to analysis and non-normally distributed data was transformed logarithmically (insulin, HOMA2 and FAI) or by taking the square root (AMH). Values are reported as mean ± standard error (SE). Baseline differences between groups were determined by one-way analysis of variance (ANOVA) and independent sample t-test. The effect of the intervention was determined by repeated measures ANOVA with time as the within-subject factor. Linear and logistic regressions were used to assess relationships between variables. Sensitivity and specificity were calculated using receiver operating characteristic (ROC) curve analysis in order to assess a possibility of baseline AMH concentrations to predict responsiveness of reproductive function to weight loss. Statistical analysis was performed using SPSS for Windows 14.0 (SPSS, Chicago, IL) and MedCalc

10 version 9.6 (MedCalc Software, Mariakerke, Belgium). An α-level of significance was set at P < Results Overall at Week 20 there were significant reductions in weight (-9.0 ± 0.8 kg), waist circumference (-10.4 ± 0.9 cm), fasting insulin (-4.2 ± 0.7 mu/l), HOMA2 (-0.55 ± 0.09), testosterone (-0.38 ± 0.08 nmol/l) and FAI (-2.6 ± 0.6) and an improvement in SHBG (6.8 ± 1.4 nmol/l) (P < for all). Of the 26 women that responded with improvements in reproductive function, six became ovulatory and improved in menstrual cyclicity (3 amenorrhoeic women regained a cycle, 2 improved cycle length variation and 1 improved cycle length). These women improved their cycle length by ± days. Sixteen women improved only in menstrual cyclicity, including 9 now having regular cycles and 5 improving in cycle length (by 6.56 ± 2.07 days) and 2 improving cycle length variation. The remaining 4 women only improved in ovulation. Women that responded with improved reproductive function had greater reductions in weight and waist circumference compared with non-responders (Table 1). There were no difference in changes in reproductive hormones or surrogate measures of insulin resistance with weight loss between responders and non-responders (Table 1) AMH levels did not change significantly overall for all subjects combined (pre 28.0 ± 2.4 v post 26.3 ± 2.1 pmol/l; P = 0.34). However, changes in AMH within individuals was inversely related to baseline AMH (r = -0.50, P < 0.001), but were not associated with improvements in menstrual cycle length or variation in cycle duration. In addition, by the end of the intervention changes in AMH did not differ between those who experienced improvements in reproductive function (responders) and those who did not (non-responders;

11 P = 0.64; Table 1). Importantly however, the responders had lower levels of AMH at baseline compared with the non-responders (P = 0.03; Table 1). ROC curve analysis indicated an upper cut-off value of 21.6 pmol/l with and area under the curve of 0.68 ± 0.07 (95% confidence intervals: 0.54 to0.80; P = 0.015), 65.4% sensitivity and 69.2% specificity to predict improvements in reproductive function as a result of weight loss. Logistic regression analysis revealed that baseline AMH (β = -0.52, P = 0.01) and the magnitude of weight loss achieved as a result of the intervention (β = -0.22, P = 0.002) both correlated with improvements in reproductive function. No hormonal parameters or measures of insulin resistance were significant in the regression model Baseline AMH levels were inversely related to the number of menstrual cycles and ovulatory cycles over the 20 week intervention (r = and r = respectively; P 0.001). AMH was also related to baseline levels of testosterone (r = 0.43, P = 0.002) and FAI (r = 0.33, P = 0.02) such that hyperandrogenic participants (testosterone > 2.0 nmol/l) had higher levels of baseline AMH compared with normoandrogenic participants (31.4 ± 2.7 v 16.6 ± 3.7 pmol/l; P = 0.004). Women that were ovulating at the commencement of the study had lower baseline AMH levels compared to anovulatory participants (22.9 ± 2.9 v 34.9 ± 3.7 pmol/l; P = 0.02). Participants who were amenorrhoeic had higher baseline AMH levels compared to oglioovulatory participants (P = 0.006, Table 2). There was no difference in AMH at baseline between hyperinsulinaemic participants (fasting insulin > 13 mu/l) and normoinsulinemic participants (28.8 ± 3.3 v 26.6 ± 3.5 pmol/l; P = 0.8) Discussion This is the first study to prospectively examine the effect of weight loss via caloric restriction on AMH and its relation to changes in reproductive function in overweight and obese women

12 with polycystic ovary syndrome and reproductive impairment. Despite considerable weight loss and improvements in reproductive function, AMH did not change significantly during the intervention. Women with higher levels of AMH at baseline experienced greater ovarian dysfunction (fewer ovulatory cycles, greater cycle irregularity and cycle length variation), and had higher levels of testosterone, suggesting that high AMH levels are associated with derangement of reproductive function. Moreover, women who demonstrated improvements in reproductive function had significantly lower AMH levels at baseline and experienced greater weight loss following the intervention compared with non-responders Whilst the effect of weight loss on AMH has not been previously studied, research investigating the effects of metformin in women with PCOS demonstrated an improvement in reproductive function that was associated with a significant decrease in AMH following 6 months of treatment (Piltonen, et al., 2005). The reduction in AMH was attributed to a decrease in antral follicle number and hyperandrogenism and improvements in insulin action and menstrual pattern (Piltonen, et al., 2005). Similarly, Fleming et al. (Fleming, et al., 2005) reported significant reductions in AMH following metformin treatment. However, AMH reductions only occurred after 4 to 8 months of treatment while improvements in ovulation were evident by 4 months. This indicates that improvements in reproductive function may precede any changes in AMH. It is therefore possible in the current study that despite observations of improved reproductive function, a longer period of intervention may be required for reductions in AMH to manifest. Changes in AMH may be are delayed until a new cohort of antral follicles has been recruited under normalised androgen and insulin conditions, replacing the follicles recruited under elevated insulin resistance and hyperandrogenism (Fleming, et al., 2005). Since approximately 3 months is required for the recruitment of a new antral follicle cohort once androgen and insulin conditions have

13 normalised (Gougeon and Lefevre, 1983), it is possible that the intervention length of the current study was insufficient for the recruitment of the new follicle cohort once insulin resistance and hyperandrogenism had been normalised. Alternatively, differences in the AMH responses observed between the present and previous studies could be related to marked differences in baseline AMH (26.6 pmol/l v ~50-90 pmol/l). It is possible that the lower levels of AMH at baseline in the present study could have potentially contributed to the lack of any significant reduction in AMH, since lower levels indicate a population with less reproductive disturbances. This is supported by the observation of an inverse relationship between baseline and the change in AMH levels. Several previous studies report large ranges of AMH values between 16 to 33 pmol/l in normal and overweight non-pcos women (Piltonen, et al., 2005, Pigny, et al., 2006, Cook, et al., 2002, Laven, et al., 2004, Pigny, et al., 2003, El-Halawaty, et al., 2007). Since varying levels of AMH appear to exist between PCOS cohorts, the present results may not be applicable to all PCOS phenotypes that display higher AMH levels. Further investigation is needed to examine AMH levels after a longer intervention period in a range of PCOS phenotypes to determine whether changes in AMH occur with weight loss and whether any such changes reflect improvements in reproductive function, and to identify the time course of weight loss required for these improvements AMH concentrations are strongly associated with the main phenotypic features of PCOS, including ovulatory dysfunction and hyperandrogenism. Consistent with our results, amenorrhoeic women with PCOS display elevated AMH compared to olgiomenorrhoeic women with PCOS, indicating an association between AMH in the pathogenesis of PCOSrelated anovulation (Pigny, et al., 2006, La Marca, et al., 2004). There is also evidence that AMH correlates with the extent of ovarian dysfunction (Laven, et al., 2004, Jonard and Dewailly, 2004), with higher levels reflecting greater impairment in menstrual cyclicity,

14 follicular development and granulosa cell function (La Marca, et al., 2004, Pellatt, et al., 2007). In addition, previous studies have shown that AMH was positively related to testosterone (Piltonen, et al., 2005, Pigny, et al., 2006, Laven, et al., 2004, Pigny, et al., 2003, Moran, et al., 2007, Eldar-Geva, et al., 2005) and FAI (Laven, et al., 2004, Moran, et al., 2007, Eldar-Geva, et al., 2005) and inversely related to SHBG (La Marca, et al., 2004), suggesting a possible link between AMH and hormonal profile. AMH levels vary between PCOS women presenting with hyperandrogenism and those with normal androgen levels (both testosterone and FAI), such that the presence of hyperandrogenism is associated with higher AMH (Pigny, et al., 2006, Eldar-Geva, et al., 2005). An association between AMH and insulin resistance has also been suggested, but there is a lack of consistency surrounding this relationship, with the majority of studies including the current study reporting no association between baseline AMH and surrogate markers of insulin resistance (Laven, et al., 2004, Pigny, et al., 2003, Fleming, et al., 2005, Eldar-Geva, et al., 2005, Bayrak, et al., 2007), one showing a positive relationship (La Marca, et al., 2004) and another a negative relationship (Chen, et al., 2008). The inconsistent results between studies may be influenced by the presence of differing PCOS phenotypes, with either primary ovarian dysfunction or insulin and obesity being the greater contributor to reproductive dysfunction. The relationship between AMH and both hormonal profile and insulin resistance is still unclear and additional research is required to specifically investigate potential weight loss effects on additional hormonal and insulin parameters that may influence reproductive function The current data and a prior study by Moran et al. (2007) suggests that higher AMH levels in women with PCOS may indicate a greater contribution of gonadotrophic or steriodogenic abnormalities and a lesser contribution of obesity and insulin resistance to menstrual dysfunction. Furthermore, AMH has been suggested as a useful clinical marker for potential

15 reproductive responsiveness to weight loss, with a recent study reporting participants with lower AMH levels (ie less ovarian dysfunction) responding to weight loss with improvements in menstrual cyclicity (Moran, et al., 2007). The present study confirms this finding, in which women with lower AMH levels experienced greater improvements in reproductive function. ROC curve analysis revealed a 68% change of predicting reproductive responsiveness following weight loss. In a recent study, AMH was used to predict response to clomiphene citrate in obese women with PCOS (El-Halawaty, et al., 2007). A cut-off value of 16.8 pmol/l was proposed with similar ROC curve values to those seen in the current study (area under the curve 0.71, sensitivity 71% and specificity 65.7%). However, the weak prediction value of AMH observed in the current study (ie. low area under the curve) suggests AMH may have a limited ability to predict reproductive responsiveness to weight loss and data from the ROC curve analysis should be interpreted with some caution. It is possible that the lack of prediction strength may have been influenced by the small sample size. Additional studies are needed in larger cohort studies to further investigate any potential use of AMH to predict reproductive response to various treatments Previous studies have reported no differences in weight loss between reproductive responders and non-responders (Holte, et al., 1995, Moran, et al., 2007). Conversely, in this current study the greater reproductive responsiveness post weight loss may be presumed to be a function of the greater weight loss achieved for responders compared to non-responders. However, we have extended this finding to explore the contribution of AMH to predict reproductive responsiveness. Due to the lack of a non-dietary control group, it is difficult to be certain the improvements are a function of the intervention and furthermore, without long-term prospective studies we are unable to determine if the improvements in reproductive function translate to improved fecund ability. Logistic regression revealed that baseline AMH levels

16 and weight loss were independent contributors to improved reproductive function. Since no other parameters measured were significant in the logistic regression model, the mechanism by which weight loss might have contributed to the improvement in reproductive function could not be determined. Although not observed in the current study, several previous studies have shown improvements in surrogate markers of insulin resistance following weight loss only in women that improved reproductive function (Huber-Buchholz, et al., 1999, Moran, et al., 2003, Palomba, et al., 2007). Additional studies are required to further examine the mechanism by which weight loss improves reproductive function in this patient group In conclusion, we have shown in overweight and obese women with PCOS that a 20 week weight loss intervention resulted in improvements in reproductive function but no change in AMH levels. Additional research is needed to examine long-term effects of weight loss on AMH levels. Participants that responded with improved reproductive function had lower levels of AMH at baseline and experienced greater weight loss. Further investigation is required to identify the mechanisms by which weight loss and lower baseline AMH levels improve reproductive function in overweight and obese women with PCOS Acknowledgements: We gratefully acknowledge Julia Weaver for assisting with trial management, Lindy Lawson and Rosemary McArthur for their assistance in the nursing activities, Gemma Williams, Xenia Cleanthous, Siew Lim and Julianne McKeough for their dietetic guidance, Mark Mano, Cathryn Seccafien, and Candita Sullivan for laboratory assistance and Brenton Bennett for conducting the AMH assays. 343

17 Funding: This project was funded by a grant from the National Health and Medical Research Council of Australia (project grant ). RT was funded by a postgraduate scholarship from the South Australia Department of Health. 347

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22 Table 1. Weight, waist circumference, insulin resistance, hormonal parameters and anti- müllerian hormone before and following weight loss for women that responded with improved reproductive function and those that did not (non-responders). 449 Responders (n=26) Non-responders (n=26) Baseline Change Baseline Change Weight (kg) ± ± 1.2* 99.0 ± ± 0.9 Waist circumference (cm) ± ± 1.3* 99.8 ± ± 1.0 Insulin (mu/l) 15.9 ± ± ± ± 1.2 HOMA ± ± ± ± 0.14 Testosterone (nmol/l) 2.50 ± ± ± ± 0.10 SHBG (nmol/l) 31.0 ± ± ± ± 1.9 FAI 9.38 ± ± ± ± 0.76 AMH (pmol/l) 23.5 ± ± ± ± 1.8 Values are presented as mean ± SE, HOMA2, homeostatic model assessment of insulin resistance; SHBG, sex-hormone binding globulin; FAI, free androgen index; AMH, antimüllerian hormone 450 * P < 0.02, significantly greater reduction in responders compared to non-responders 451 P < 0.03, significantly lower compared to non-responders at baseline. 452

23 Table 2. Baseline anti-müllerian hormone and the change in anti-müllerian hormone following weight loss for women who were amenorrhoeic, anovulatory and oglio-ovulatory. Baseline AMH (pmol/l) Change in AMH (pmol/l) Amenorrhoeic (n=8) 44.0 ± ± 2.3 Anovulatory (n=14) 29.7 ± ± 3.2 Oglio-ovulatory (n=30) 22.9 ± 2.9* -2.3 ± Values are presented as mean ± SE, AMH, anti-müllerian hormone * P = 0.006, significantly lower than amenorrhoeic participants 458