• ● General Criteria for all groups

‣ Participant is willing and able to give informed consent for participation in the study.

⁃ Female, aged between 16 and 45 years of age. As IVF is not undertaken in women less that 18 years, this group will between 18 and 45 years o

‣ ● PCOS (Group 1, 2 and 3)

⁃ Currently under investigation for or having diagnosis of PCOS having displayed one or more of the following: Hyperandrogenism, Ovulation Dysfunction and Polycystic ovaries on ultrasound (known as the Rotterdam criteria)

‣ ● PCOS Controls (Group 4 and 5)

⁃ Patients under gynaecological investigation or having assisted reproduction

⁃ Exhibit no features of PCOS

‣ ● Miscarriage Group (Group 6)

⁃ Have had at least two previous miscarriages

⁃ Recruited at any time after their second menstrual cycle following a miscarriage

‣ ● Miscarriage Controls (Group 7)

⁃ Patients will have had zero or no more than one miscarriage and having fertility investigations.

‣ ● Pregnant GDM (Group 8)

⁃ Pregnant women at least 28 weeks gestation with :

⁃ 1\) A fasting plasma glucose of 5.1mmol/L or above or

⁃ 2\) A 1 hr plasma glucose of 10mmol/L or

⁃ 3\) A 2-hr plasma glucose level of 8.5mmol/L or above

‣ ● Pregnant ICP (Group 9)

⁃ Women at least 28 weeks gestation with :

⁃ Raised ALT or raised bile acids in the context of pruritus with no rash

⁃ ALT (\>32iu/l) and bile acids (\>14micromol/l) Pregnant Control (Group 10)

⁃ Pregnant women at least 28 weeks gestation with no diagnosis of GDM or ICP