[1] Ashford & St Peters Hosp NHS Fdn Trust, Obstet & Gynaecol, Surrey, England
[2] Ashford & St Peters Hosp NHS Fdn Trust, Surg Site Infect Surveillance Team, Surrey, England
[3] Ashford & St Peters Hosp NHS Fdn Trust, Dept Qual, Surrey, England
[4] Univ Bristol, Sch Physiol Pharmacol & Neurosci, Bristol, Avon, England
[5] Ashford & St Peters Hosp NHS Fdn Trust, Dept Cardiol, Surrey, England
[6] Ashford & St Peters Hosp NHS Fdn Trust, Dept Endocrinol, Surrey, England
[7] Royal Holloway Univ London, Inst Cardiovasc Res, Egham TW20 0EX, Surrey, England