(1) Aim of the project:

Our overall aim is to determine the prevalence of hyperandrogenism (clinical and / or biochemical evidence of androgen excess) in two large cohorts of post-menarchal adolescent girls followed prospectively prenatally and from birth in the UK and Finland. We will determine the extent to which androgen levels are related to early developmental changes (pre natal androgen exposure, early postnatal weight gain), familial factors (maternal history of PCOS) and whether hyperandrogenism is independently associated with cardiovascular risk factors during adolescence.

(2) Objectives:

1. Main objectives:

a. To determine the prevalence of hyperandrogenism in two populations of post-menarchal adolescent girls from the UK and Finland.

b. To explore the nature of the association between serum androgen levels and clinical features of polycystic ovary syndrome (PCOS) such as ovulatory dysfunction and hirsutism in postmenarchal adolescence.

2. Secondary objectives:

a. To determine the relationship between serum androgens at adolescence with early developmental factors (birth weight, cord blood androgen levels, rates of early postnatal weight gain).

b. To determine the relationship between serum androgen levels at adolescence with maternal history of PCOS (irregular periods, hirsutism, sub-fertility) and maternal serum androgens and anti-Mullerian hormone (AMH) levels.

c. To determine the relationship between serum androgens and cardiovascular risk factors at adolescence (lipids, insulin sensitivity, hsCRP, Adiponectin) and whether this is independent of BMI and body fat mass.

d. To use genetic information (including genome-wide scan data available for both cohorts) to make inferences about causal relationships through Mendelian randomisation approaches.