Acknowledgements

I would like to thank my supervisors Dr. Richard Hoffman and Prof. Anwar Baydoun for all their support and guidance over the past three years, their experience has been invaluable throughout my studies. I would like to thank all the people in the labs who have given me support and help especially Gareth, Dirk, and Jen; they were always there when I needed them. Special thanks must be given to Di, Jon and Jenny for all their hard work, encouragement and technical support (even at short notice!) during my PhD. Special thanks go to the nurses and midwives at the Queen Elizabeth II hospital, Welwyn Garden City, for all their cooperation in acquiring samples for this study. I would also like to thank my family and friends, who made it possible for me to complete my studies. All their encouragement and help was always gratefully received and will not be forgotten. Special thanks go to my Mum, Dad and Emma, without their support I would have not made it this far. I