Anti-Müllerian hormone: correlation with testosterone and oligo- or amenorrhoea in female adolescence in a population-based cohort study.

STUDY QUESTIONS: Can serum anti-Müllerian hormone (AMH) levels measured in female adolescents predict polycystic ovary syndrome (PCOS)-associated features in adolescence and early adulthood? SUMMARY ANSWER: AMH levels associated well with PCOS-associated features (such as testosterone levels and oligoamenorrhoea) in adolescence, but was not an ideal marker to predict PCOS-associated features in early adulthood. WHAT IS KNOWN ALREADY: Several studies have reported that there is a strong correlation between antral follicle count and serum AMH levels and that women with PCOS/PCO have significantly higher serum AMH levels than women with normal ovaries. Other studies have reported an association between AMH serum levels and hyperandrogenism in adolescence, but none has prospectively assessed AMH as a risk predictor for developing features of PCOS during adulthood. STUDY DESIGN, SIZE, DURATION: A subset of 400 girls was selected from the prospective population-based Northern Finland Birth Cohort 1986 (n = 4567 at age 16 and n = 4503 at age 26). The population has been followed from 1986 to the present. PARTICIPANTS/MATERIAL, SETTING, METHODS: At age 16, 400 girls (100 from each testosterone quartile: 50 with oligo- or amenorrhoea and 50 with a normal menstrual cycle) were selected at random from the cohort for AMH measurement. Metabolic parameters were also assessed at age 16 in all participants. Postal questionnaires enquired about oligo- or amenorrhoea, hirsutism, contraceptive use and reproductive health at ages 16 and 26. MAIN RESULTS AND ROLE OF CHANCE: There was a significant correlation between AMH and testosterone at age 16 (r = 0.36, P < 0.001). AMH levels at age 16 were significantly higher among girls with oligo- or amenorrhoea compared with girls with normal menstrual cycles (35.9 pmol/l [95% CI: 33.2;38.6] versus 27.7 pmol/l [95% CI: 25.0;30.4], P < 0.001). AMH at age 16 was higher in girls who developed hirsutism at age 26 compared with the non-hirsute group (31.4 pmol/l [95% CI 27.1;36.5] versus 25.8 pmol/l [95% CI 23.3;28.6], P = 0.036). AMH at age 16 was also higher in women with PCOS at age 26 compared with the non-PCOS subjects (38.1 pmol/l [95% CI 29.1;48.4] versus 30.2 pmol/l [95% CI 27.9;32.4], P = 0.044). The sensitivity and specificity of the AMH (cut-off 22.5 pmol/l) for predicting PCOS at age 26 was 85.7 and 37.5%, respectively. The addition of testosterone did not significantly improve the accuracy of the test. There was no significant correlation between AMH levels and metabolic indices at age 16. IMPLICATIONS, REASONS FOR CAUTION: AMH is related to oligo- or amenorrhoea in adolescence, but it is not a good marker for metabolic factors. The relatively low rate of participation in the questionnaire at age 26 may also have affected the results. AMH was measured in a subset of the whole cohort. AMH measurement is lacking international standardization and therefore the concentrations and cut-off points are method dependent. WIDER IMPLICATIONS FOR THE FINDINGS: Using a high enough cut-off value of AMH to predict which adolescents are likely to develop PCOS in adulthood could help to manage the condition from an early age due to a good sensitivity. However, because of its low specificity, it is not an ideal diagnostic marker, and its routine use in clinical practice cannot, at present, be recommended. STUDY FUNDINGS AND COMPETING INTERESTS: The study was funded by a grant from Wellcome Trust (089549/Z/09/Z) to H.L., S.F. and M.-R.J. Study funding was also received from Oulu University Hospital Research Funds, Sigrid Juselius Foundation and the Academy of Finland. None of the authors have any competing interest to declare.

Menstrual disorders in adolescence: a marker for hyperandrogenaemia and increased metabolic risks in later life? Finnish general population-based birth cohort study.

STUDY QUESTION: Are self-reported menstrual disorders associated with hyperandrogenaemia and metabolic disturbances as early as in adolescence? SUMMARY ANSWER: Menstrual disorders at the age 16 are a good marker of hyperandrogenaemia, and an adverse lipid profile was associated with higher androgen levels. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Hyperandrogenism per se has been suggested to be a significant metabolic risk factor in women and a cause of physical and psychological morbidity in adolescent girls. A weak positive correlation has been described between hyperandrogenaemia and obesity in adolescent girls, but the clinical consequences are still poorly understood. Hyperandrogenism and insulin resistance are also key features of polycystic ovary syndrome (PCOS), and women with PCOS are consequently at an increased risk of developing type 2 diabetes mellitus and/or metabolic syndrome, and may have increased cardiovascular morbidity. Our findings confirm that the association between menstrual disorders, hyperandrogenism, obesity and metabolic risks is already evident in adolescence. STUDY DESIGN: This population-based, cross-sectional study used postal questionnaires to targeting 15-16-year-old girls in the Northern Finland Birth Cohort 1986 (n= 4567). PARTICIPANTS AND SETTING: There were 3669 girls who answered the postal questionnaire and out of 3373 girls who also underwent clinical examinations and blood tests, 2448 were included in the analyses. The questionnaire included one question about the regularity and length of the menstrual cycle: 'Is your menstrual cycle (the interval from the beginning of one menstrual period to the beginning of the next period) often (more than twice a year) longer than 35 days?' The girls who answered 'yes' to this question were considered to be suffering from menstrual disorders and were classified as 'symptomatic'. The girls who answered 'no' were defined as 'non-symptomatic'. MAIN RESULTS AND THE ROLE OF CHANCE: There were 709 (29%) girls who reported menstrual disorders (symptomatic girls) and 1739 who had regular periods (non-symptomatic girls). In the whole population and in both study groups, there were significant correlations between body mass index (BMI) (and waist-to-hip ratio), hyperandrogenaemia and metabolic parameters. Symptomatic girls exhibited significantly higher serum concentrations of testosterone (P= 0.010), lower levels of sex hormone-binding globulin (P =0.042) and higher free androgen indices [FAIs; geometric mean 3.38 (interquartile range (IQR): 2.27, 5.18) versus 3.08 (IQR: 2.15, 4.74), P= 0.002]. The two groups had comparable BMI and insulin sensitivity, and serum levels of glucose, insulin and lipids. There was a significant linear trend towards higher FAI values in the higher BMI quartiles in both symptomatic and non-symptomatic girls. In the whole population, there was a statistically significant linear decrease in high-density lipoprotein concentrations (P < 0.001) and higher triglyceride concentrations (P =0.004) in the upper FAI quartile. IMPLICATIONS: Information regarding menstrual disorders in adolescence is a good marker of hyperandrogenaemia and may be an early risk factor for the development of PCOS in adulthood. The association between obesity, hyperandrogenism and metabolic risks is already evident in adolescence, which strengthens the importance of noting menstrual disorders at an early stage. BIAS, LIMITATIONS, GENERALIZABILITY: The cross-sectional nature of the study does not allow us to draw conclusions concerning the metabolic risks of this population in later life. The diagnosis of menstrual disorders was based on a questionnaire, suggesting a risk of information bias in reporting the symptoms. This study was not designed to diagnose PCOS, as ultrasonography was not available and there was no clinical evaluation of hyperandrogenism (i.e. hirsutism). However, we were able to take into account potential confounding factors in the analyses. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the Finnish Medical Society Duodecim, the North Ostrobothnia Regional Fund, the Academy of Finland (project grants 104781, 120315, 129269, 1114194, SALVE), University Hospital Oulu, Biocenter, University of Oulu, Finland (75617), the European Commission (EURO-BLCS, Framework 5 award QLG1-CT-2000-01643) and the Medical Research Council, UK (PrevMetSyn/SALVE). None of the authors have any conflict of interest to declare.