women: - taking oestrogen supplements or oestrogen receptor antagonists - with abnormal genital bleeding - with a history of breast cancer - with a history of endometrial or ovarian cancer - with untreated endometrial hyperplasia men: • taking hormone therapies (e.g. for prostate cancer) any subject: - failure to obtain consent - taking lamotrigine - with a thromboembolic disorder (e.g. protein c or protein s deficiency, antithrombin iii deficiency) - with pre-existing liver or renal disease - with known allergy to exogenous oestrogens - with a history of porphyria - with a history of thromboembolic event including deep vein thrombosis, thromboembolic stroke or pulmonary emboli - taking part in another interventional clinical trial

women: - taking oestrogen supplements or oestrogen receptor antagonists - with abnormal genital bleeding - with a history of breast cancer - with a history of endometrial or ovarian cancer - with untreated endometrial hyperplasia men: • taking hormone therapies (e.g. for prostate cancer) any subject: - failure to obtain consent - taking lamotrigine - with a thromboembolic disorder (e.g. protein c or protein s deficiency, antithrombin iii deficiency) - with pre-existing liver or renal disease - with known allergy to exogenous oestrogens - with a history of porphyria - with a history of thromboembolic event including deep vein thrombosis, thromboembolic stroke or pulmonary emboli - taking part in another interventional clinical trial