Gabor Kovacs is a reproductive gynecologist, with nearly forty years of experience in IVF. He is an Honorary Life Member of The International Federation of Fertility Societies (IFFS), Honorary Life Member of The Fertility Society of Australia, and received the Distinguished Alumni Award, Monash University, and Distinguished Service Medal, of The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. He has edited 14 books for Cambridge, and this book is one of a series of four books: How to Improve Preconception Health to Maximize IVF Success (Cambridge, 2018); Male and Sperm Factors that Maximize IVF Success (forthcoming), and How to Prepare the Endometrium to Maximize Implantation Rates and IVF Success (forthcoming). Anthony Rutherford has worked in reproductive medicine since 1985, establishing one of the largest National Health Service IVF units in the UK in Leeds in 1991. Mr Rutherford was one of the first to introduce vaginal ultrasound and the large-scale use of GnRH analogues in IVF protocols into the UK. He has been actively involved nationally with over seventeen years as a Board member of the British Fertility Society, including as past chairman in 2009 to 2011, and in further education through the Royal College of Obstetricians and Gynaecologists. He is a founding member of the British Society of Gynaecological Endoscopy, and currently he is a Board member of the Human fertilization & Embryo Authority, the UK IVF regular. David K. Gardner is a world-renowned embryologist with over thirty-five years' experience. He is a Redmond Barry Distinguished Professor in the School of BioSciences at the University of Melbourne, the Scientific Director of Melbourne IVF, and a Fellow of the Australian Academy of Science. He is the current President of the Alpha, representing Scientists in Reproductive Medicine, and Section Editor of Reproductive BioMedicine Online. He has edited 15 books on human IVF and embryology, is a pioneer of human blastocyst culture, and is one of the most highly cited scientists in reproductive biology and reproductive medicine.