Is polycystic ovary syndrome an exception for reproductive ageing?

Abstract

OBJECTIVE: The level of Anti Mullerian Hormone (AMH), an important inhibitor of primordial follicle pool depletion, is increased in women with polycystic ovary syndrome (PCOS) suggesting a delay in the process of ovarian ageing. We therefore examined the pattern of decrease in AMH level over a period of 10 years and estimated the age of menopause in PCOS and normo-ovulatory women in a population based cohort.DESIGN: A subset of 1002 non menopause women aged 16-44 were randomly selected from Tehran Lipid and Glucose Cohort Study. 85 cases of PCOS were diagnosed in this subset using National Institutes of Health (NIH) criteria. Subjects were grouped into three BMI (< 25, 25-30, and > 30) and age groups (<25, 25-35, and >35 years). For each case of PCOS one subject was randomly selected from all available subjects in the rest of the cohort matched on BMI and Age groups.MATERIALS AND METHODS: AMH level were assessed at the time of recruitment (T1) and twice after that (T2 and T3) at about 3 years intervals. Regression analysis was used to assess the degree of change over time intervals. AMH levels were mapped against the age of the subject at the time of assessment and the best mathematical fit was plotted. The intersection with a cut off value less than 0.1ng/ml was calculated and used to estimate age at menopause.RESULTS: The mean AMH level was higher in patients with PCOS compared with normal controls (repeated measure p<0.001). However relative decrease in AMH levels over time was on average10 times faster in patients with PCOS in the first interval and plateaued after that. Estimated average ages at menopause were about 52 and 51 in patients with PCOS and normal controls respectively.CONCLUSIONS: Although AMH levels are higher in PCOS women, their reproductive life spans are not extended and they reach menopause at a similar age to normo-ovulatory women. OBJECTIVE: The level of Anti Mullerian Hormone (AMH), an important inhibitor of primordial follicle pool depletion, is increased in women with polycystic ovary syndrome (PCOS) suggesting a delay in the process of ovarian ageing. We therefore examined the pattern of decrease in AMH level over a period of 10 years and estimated the age of menopause in PCOS and normo-ovulatory women in a population based cohort. DESIGN: A subset of 1002 non menopause women aged 16-44 were randomly selected from Tehran Lipid and Glucose Cohort Study. 85 cases of PCOS were diagnosed in this subset using National Institutes of Health (NIH) criteria. Subjects were grouped into three BMI (< 25, 25-30, and > 30) and age groups (<25, 25-35, and >35 years). For each case of PCOS one subject was randomly selected from all available subjects in the rest of the cohort matched on BMI and Age groups. MATERIALS AND METHODS: AMH level were assessed at the time of recruitment (T1) and twice after that (T2 and T3) at about 3 years intervals. Regression analysis was used to assess the degree of change over time intervals. AMH levels were mapped against the age of the subject at the time of assessment and the best mathematical fit was plotted. The intersection with a cut off value less than 0.1ng/ml was calculated and used to estimate age at menopause. RESULTS: The mean AMH level was higher in patients with PCOS compared with normal controls (repeated measure p<0.001). However relative decrease in AMH levels over time was on average10 times faster in patients with PCOS in the first interval and plateaued after that. Estimated average ages at menopause were about 52 and 51 in patients with PCOS and normal controls respectively. CONCLUSIONS: Although AMH levels are higher in PCOS women, their reproductive life spans are not extended and they reach menopause at a similar age to normo-ovulatory women.